Dissertations / Theses: 'Social impacts of climate change and variability'

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Raymond, Florian. "Longs épisodes secs hivernaux dans le bassin méditerranéen et conditions atmosphériques associées : variabilité contemporaine et future (1957-2100)." Thesis, Bourgogne Franche-Comté, 2017. http://www.theses.fr/2017UBFCK017/document.

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Dans un contexte de changement climatique actuel et futur, se traduisantnotamment par un assèchement déjà observé en Méditerranée, cette thèse seconcentre sur l’étude de la variabilité contemporaine et future (1957-2100)des événements de très longs épisodes secs (eTLES) hivernaux (septembreavril)dans le bassin méditerranéen. Une méthodologie originale a été développéeau cours de cette thèse pour appréhender les eTLES comme desévénements climatiques singuliers, caractérisés par des critères de localisation,de durée et d’extension spatiale.Sur la période contemporaine (1957-2013), 76 eTLES ont été détectésdans le bassin méditerranéen. Ces événements sont répartis en 4 principalesconfigurations géographiques : Nord-Est, Ouest, Dispersés & Restreints etSud-Est. Les configurations de types Nord-Est et Ouest sont associées àdes blocages anticycloniques localisés à environ 1 000 km au nord-ouestdes secteurs principalement affectés par les eTLES, favorisant un ciel dégagéet l’absence de précipitations. Les configurations de types Dispersés& Restreints et Sud-Est sont particulières, car la première est caractériséecomme étant une classe résiduelle regroupant des eTLES à faible extensionspatiale répartis dans l’ensemble du bassin, la seconde est caractérisée pardes eTLES saisonniers qui s’insèrent dans la continuité de l’été sec observéà l’est du bassin méditerranéen.Les grands régimes de circulation atmosphérique du domaine Euro-Atlantique montrent un certain contrôle sur les eTLES. Ainsi, la phasepositive de l’oscillation nord-atlantique (NAO+) est le seul régime à êtreclairement favorable au développement d’eTLES sur la quasi-totalité du bassin.Le régime est-atlantique (EA) ne montre pas de contrôle sur les eTLES,atlantic ridge (AR) et la phase négative de l’Oscillation Nord-Atlantique(NAO-) sont deux régimes généralement défavorables aux eTLES. Cependant,des eTLES sont pourtant associés aux régimes AR, EA et NAO-. Pourcela, il faut que ces trois régimes de circulation soient associés à des pressionsatmosphériques légèrement plus élevées au nord-ouest des secteursimpactés par les eTLES, comparativement à leur climatologie respective.Les longues séquences des régimes AR, EA et NAO+, représentatives d’unecertaine stabilité atmosphérique durable dans le temps, sont préférentiellementassociées aux eTLES, contrairement aux courtes séquences de ces troisrégimes. À l’inverse, les longues séquences du régime NAO-, renforçant les basses pressions atmosphériques sur l’Europe et le bassin méditerranéen,sont peu associées aux eTLES.Bien que les deux modèles ALADIN52 et LMDZ4-NEMOMED8 affichentdes résultats différents à plusieurs niveaux, ils s’accordent tout demême à montrer que les eTLES devraient être de plus en plus longs d’icià l’horizon 2100, de façon encore plus marquée pour la trajectoire RCP8.5que RCP4.5. Une analyse multi-modèles comprenant 12 simulations CMIP5montre qu’en moyenne par saison, la pression réduite au niveau de la meraurait tendance à augmenter sur l’océan Atlantique, au large des côtes françaiseset sur le centre du bassin méditerranéen, de façon robuste pour latrajectoire RCP8.5. À l’inverse, la fréquence et la durée des séquences des 4régimes de circulation atmosphérique ne semblent pas être amenées à évoluerd’ici à l’horizon 2100.Une étude est enfin menée pour constater les impacts des eTLES surla production agricole en Espagne. Le nombre de jours d’eTLES impactedavantage les rendements d’orge, de blé et d’avoine (espèces d’hiver et cultivéesau travers d’une agriculture pluviale) que les simples ratios de jourssecs et les cumuls de pluie en Espagne. Une étude de cas réalisée sur deuxsaisons ayant reçu des cumuls de pluie comparables montre qu’en plus desrendements, un eTLES provoque une baisse significative de l’humidité dessols et du débit du fleuve Èbre
In the context of climate change, as reflected by a dryer Mediterraneanbasin, this thesis focused on the study of the contemporary and future variability(1957-2100) of the wintertime (September to April) very long dryspells events (called VLDSe) in the Mediterranean basin. An original methodologywas developed in this thesis in order to define VLDSe as singularclimatic events, characterized by location, duration and spatial extent criteria.76 VLDSe were detected in the Mediterranean basin on the contemporaryperiod (1957-2013). These events are divided into 4 main geographicalpatterns: North-East, West, Scattered Localized and South-East. North-East and West configurations are associated with anticyclonic conditionslocated approximately 1 000 km northwestern to the areas affected by theVLDSe, favoring a clear sky and no precipitations. The Scattered Localizedand South-East configurations are special: the first one is characterized asa residual class grouping VLDSe with small spatial extent and distributedthroughout the entire basin, and the second one is characterized by seasonalVLDSe which are the continuation of the dry summer observed in the eastof the Mediterranean basin.Euro-Atlantic weather regimes have some control on the VLDSe. Thepositive phase of the north-atlantic oscillation regime (NAO+) is the onlyone that is clearly favorable to the development of VLDSe on almost the entirebasin. The east-atlantic regime (EA) does not show any control on theVLDSe, and the atlantic ridge (AR) and the negative phase of the northatlanticoscillation (NAO-) regimes are generally detrimental to VLDSe. However,some VLDSe can sometimes be associated with AR, EA and NAOregimes.This requires these three weather regimes to be associated withslightly higher atmospheric pressure northwest of the areas impacted bythe VLDSe, compared to their respective climatology. Long duration of theAR, EA and NAO+ regimes, which are coupled with sustained atmosphericstability, are preferentially associated with VLDSe, in contrast to the shortduration. Conversely, the long duration of the NAO- regime, reinforcingthe low atmospheric pressure on Europe and the Mediterranean basin, areweakly associated with VLDSe.Although the two climate models ALADIN52 and LMDZ4-NEMOMED8 differ in several respects, they agree in that VLDSe should be longer by 2100,especially in the RCP8.5 trajectory. A multi-model analysis with 12 CMIP5simulations shows that wintertime sea-level pressure tends to increase in theAtlantic Ocean, off the French coast and in the central the Mediterraneanbasin for the RCP8.5 trajectory. Conversely, the frequency and duration ofthe 4 weather regimes do not show significant trends until the end of the21st century.Finally, a study is carried out to assess the impact of VLDSe on agriculturalproduction in Spain. The number of VLDSe days has a larger impactson the yields of barley, wheat and oats (winter species and cultivatedthrough rainfed agriculture) than the simple ratio of dry days or seasonalrainfall amounts in Spain. A two-season case study, based on seasons withcomparable rainfall amounts, shows that in addition to yields, a VLDSecauses a significant decrease in soil moisture and in the Ebro River flow

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Lau, Hoppa. "Impacts of climate variability and climate change on prairie wheat yield." Thesis, National Library of Canada = Bibliothèque nationale du Canada, 2001. http://www.collectionscanada.ca/obj/s4/f2/dsk3/ftp04/MQ58810.pdf.

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Parsons, Luke Alexander, and Luke Alexander Parsons. "Sources and Impacts of Modeled and Observed Low-Frequency Climate Variability." Diss., The University of Arizona, 2017. http://hdl.handle.net/10150/625552.

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Here we analyze climate variability using instrumental, paleoclimate (proxy), and the latest climate model data to understand more about the sources and impacts of low-frequency climate variability. Understanding the drivers of climate variability at interannual to century timescales is important for studies of climate change, including analyses of detection and attribution of climate change impacts. Additionally, correctly modeling the sources and impacts of variability is key to the simulation of abrupt change (Alley et al., 2003) and extended drought (Seager et al., 2005; Pelletier and Turcotte, 1997; Ault et al., 2014). In Appendix A, we employ an Earth system model (GFDL-ESM2M) simulation to study the impacts of a weakening of the Atlantic meridional overturning circulation (AMOC) on the climate of the American Tropics. The AMOC drives some degree of local and global internal low-frequency climate variability (Manabe and Stouffer, 1995; Thornalley et al., 2009) and helps control the position of the tropical rainfall belt (Zhang and Delworth, 2005). We find that a major weakening of the AMOC can cause large-scale temperature, precipitation, and carbon storage changes in Central and South America. Our results suggest that possible future changes in AMOC strength alone will not be sufficient to drive a large-scale dieback of the Amazonian forest, but this key natural ecosystem is sensitive to dry-season length and timing of rainfall (Parsons et al., 2014). In Appendix B, we compare a paleoclimate record of precipitation variability in the Peruvian Amazon to climate model precipitation variability. The paleoclimate (Lake Limón) record indicates that precipitation variability in western Amazonia is ‘red’ (i.e., increasing variability with timescale). By contrast, most state-of-the-art climate models indicate precipitation variability in this region is nearly'‘white' (i.e., equally variability across timescales). This paleo-model disagreement in the overall structure of the variance spectrum has important consequences for the probability of multi-year drought. Our lake record suggests there is a significant background threat of multi-year, and even decade-length, drought in western Amazonia, whereas climate model simulations indicate most droughts likely last no longer than one to three years. These findings suggest climate models may underestimate the future risk of extended drought in this important region. In Appendix C, we expand our analysis of climate variability beyond South America. We use observations, well-constrained tropical paleoclimate, and Earth system model data to examine the overall shape of the climate spectrum across interannual to century frequencies. We find a general agreement among observations and models that temperature variability increases with timescale across most of the globe outside the tropics. However, as compared to paleoclimate records, climate models generate too little low-frequency variability in the tropics (e.g., Laepple and Huybers, 2014). When we compare the shape of the simulated climate spectrum to the spectrum of a simple autoregressive process, we find much of the modeled surface temperature variability in the tropics could be explained by ocean smoothing of weather noise. Importantly, modeled precipitation tends to be similar to white noise across much of the globe. By contrast, paleoclimate records of various types from around the globe indicate that both temperature and precipitation variability should experience much more low-frequency variability than a simple autoregressive or white-noise process. In summary, state-of-the-art climate models generate some degree of dynamically driven low-frequency climate variability, especially at high latitudes. However, the latest climate models, observations, and paleoclimate data provide us with drastically different pictures of the background climate system and its associated risks. This research has important consequences for improving how we simulate climate extremes as we enter a warmer (and often drier) world in the coming centuries; if climate models underestimate low-frequency variability, we will underestimate the risk of future abrupt change and extreme events, such as megadroughts.

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Parry, Louise Margaret. "Monsoon variability, climate change and impacts on hydrology in the Himalaya." Thesis, University of Bristol, 2016. https://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.715813.

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Crimmins, Michael, and Gregg Garfin. "Climate Change and Wildfire Impacts in Southwest Forests and Woodlands (Climate Change and Variability in Southwest Ecosystems Series)." College of Agriculture and Life Sciences, University of Arizona (Tucson, AZ), 2006. http://hdl.handle.net/10150/146955.

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4 pp.
Southwest forests are complex systems that are influenced by climate variability. Wildfires naturally occur in these forests and woodlands, but with an increasing population, land management decisions are becoming more difficult. This publication is a result of discussions from the "Workshop on Climate Variability and Ecosystem Impacts" that was sponsored by UA Cooperative Extension in February 2005. It provides a summary of the current situation, a summary of climate change science for land management, and a brief description of suggested future research in climate science as it relates to forests and woodlands.

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Thanke, Wiberg Joakim. "Local Impacts of Climate Change on Fortum´s Hydropower Production." Thesis, KTH, Vattendragsteknik, 2016. http://urn.kb.se/resolve?urn=urn:nbn:se:kth:diva-183396.

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Background: Climate change and the consequences of global warming is probably one of the greatest issues of our time. Among other concerns, global warming is thought to have a great impact on hydrology worldwide. When the atmosphere warms up, river runoff patterns are altered. Nevertheless these future changes are assumed to increase the hydropower potential in some countries. In the public debate it is often referred to a nine year old investigation claiming an increase of 15-20 % in Swedish energy production from hydropower due to the river runoff increase. On the other hand recent research is hinting that the effect of global warming might be masked by climate variability in the nearest future. This study seeks to investigate whether or not the hydropower-intensive company Fortum will benefit from increased future hydropower potential due to climate change. Methods: Using historical data, the impacts of global warming on the future potential power production in different types of hydropower plants are estimated by the statistical approach of probability density functions. Moreover spectral analysis is used to investigate the impacts of climate variability in various Swedish watersheds. The study investigates both the nearest future, represented by the years 2021-2050, and the end of the century, represented by the years 2069-2098. Results: The future hydropower production is shown to be strongly dependent on the geographical location of a power plant and of the specific power plant type. Although all Swedish rivers where Fortum operates is given more river runoff in the future, some hydropower plants might suffer from lower hydropower potential due to increased runoff variability. However all reservoir-type power plants in the study, with ability to store water, are calculated to benefit from increased river runoff. Only the run-of-river type power plants, operating with unregulated river flow, are not yet proven to benefit from a changing climate. When considering both specific river and type of power plant, this study indicates that the hydropower potential in the rivers where Fortum operates is expected to increase with 4-15 % towards the end of the century. The one exception is the unregulated river Västerdalälven where this study indicates a possibility of decreased hydropower potential due to climate change. The results of the spectral analysis indicates that up to 30 % of the coefficient of variation in the monthly mean runoff data is explained by low-frequent periodic fluctuations due to natural climate variability, linked to somewhat predictable climate indices. Conclusion: Natural climate variability is likely to be the dominating factor in the nearest future, at least in regulated rivers. Although there are uncertainties about the future potential power production in the run-of-river type power plants, one cannot deny that most of the Swedish rivers where the major hydropower companies operate are strongly regulated. Adding the fact that river runoff will increase as a consequence of global warming, Fortum is likely to gain from an increased hydropower potential. However, this present study highlights the inaccuracies in using the out-of-date estimation of 15-20 % hydropower-potential increase as a forecast of future potential power production in all Fortum-operated hydropower plants.

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Fowler, Hayley Jane. "The impacts of climatic change and variability on water resources in Yorkshire." Thesis, University of Newcastle Upon Tyne, 2000. http://hdl.handle.net/10443/432.

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Observational evidence and future climate change scenarios suggest an amplification of climatic contrasts across the UK. This is seen most prominently in the marked increase in notable flood events and drought episodes and may profoundly affect water resource systems in vulnerable areas, as exemplified by the 1995 Yorkshire drought. The 1995-96 drought resulted in severe stress to the Yorkshire water supply, necessitating the emergency measure of tanking in water from outside the region, and was caused by an unusual pattern of weather and precipitation. This research is an investigation into both natural climatic variability and possible future climate change in Yorkshire aiming to quantify the risk of future occurrence of severe drought events, such as that of 1995. Historical drought characteristics and spatial-temporal precipitation variability in Yorkshire are examined and linked to synoptic weather patterns. A multi-site stochastic rainfall model is then developed using conditioning by synoptic weather types. The model can account for spatial variability and allows the concurrent simulation of precipitation time-series for very different climatological sub-regions within the same water resource area. This model is used to investigate the impact of natural climatic variability and possible future climate change upon water resource reliability, resilience and vulnerability in Yorkshire. The structure of the stochastic rainfall model enables the impact of variations in weather type persistence or frequency to be investigated. In addition, rainfall model statistics can be altered to simulate instances of increased precipitation intensity or proportion dry days for example, for individual weather groups. The UKCIP98 Medium-High climate change scenarios for 2021- 2050 and 205 1-2080 are investigated using modifications to weather type frequency, precipitation and potential evapotranspiration. Results indicate that water resources in Yorkshire are likely to become more reliable on average under the examined climate change scenarios due to increased winter precipitation. However, model simulations also suggest a reduction in resource resilience and increased vulnerability to drought. Severe droughts comparable to that of 1995 show only a slight increase in frequency by 2080. However, there will be a significant increase in both magnitude and duration of severe drought, as a consequence of summer precipitation reductions and increased climatic variability. This methodology of simulating the impacts of potential atmospheric circulation change on precipitation regimes can provide a basis for the future planning and management of water resource systems.

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O'Brien, Geoff. "Disaster management, climate change and variability and social resilience." Thesis, Northumbria University, 2008. http://nrl.northumbria.ac.uk/3142/.

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Accelerated climate change and increasing climate variability caused by increasing anthropogenic greenhouse gas emissions is the single largest threat to the international goals of sustainable development, the Millennium Development Goals (MDGs) and disaster risk reduction. Global discourses recognise the need for effective and sustainable responses to produced climate risks. The risk types likely to occur are known, but only in broad terms. That they are produced by human action is accepted; but their scale, severity, longevity and frequency are not known. The challenge for policymakers is developing an effective framework within which sustainable responses can be formulated. Addressing the problems of produced risks requires a comprehensive approach to risk management to be effective. The mechanisms within the climate change, sustainable development and disaster risk reduction discourses are not sufficiently effective or integrated to respond to this challenge. Fundamental reform to current modes of risk reduction is needed, but this can only be achieved by a shift in the dominant perspective on formulating sustainable responses. This requires a shift to an enabling policy framework that encourages bottom-up resilient responses. Resilience is argued as a tool for policy development that can enhance adaptive capacity to current climate risks and shape energy policy to respond to mitigate future climate risks.

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Ambrosino, C. "Rainfall variability in southern Africa : drivers, climate change impacts and implications for agriculture." Thesis, University College London (University of London), 2011. http://discovery.ucl.ac.uk/1322446/.

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Southern Africa is characterised by a high degree of rainfall variability affecting agriculture among other sectors. The focus of this study is to investigate such variability and to identify stable relationships with its potential drivers in the climate system. These relationships are used as the basis for the statistical downscaling of climate model (GCM) outputs. From the simulated rainfall, indices representative of growing season characteristics are computed with the final purpose of studying the implications on maize cropping under a future climate change scenario. The analysis uses generalized linear models (GLMs), which allow the investigation of the relationships between different components of the climate system (geographical and climatic drivers) simultaneously. Initially, the effects of various climate indicators upon monthly regional (for all southern Africa) precipitation occurrences and amounts are characterised. Six climate factors are found to drive part of the rainfall variability in the region and their modelled effect upon rainfall occurrences and amounts agrees broadly with previous studies. Among the retained indices, relative humidity and El Niño accounted for the highest degree of explained variability. The location and intensity of the jet stream is also found to have a statistically significant and physically meaningful effect upon rainfall variability. Although effective for the analysis of monthly regional precipitation, and used to investigate future regional projections, the models do not perform adequately at more local spatial scales such as station locations or few km grids. The same methodology is, therefore, applied to characterise daily precipitation variability at multiple locations within a smaller region. The small scale statistical models capture adequately the seasonal and annual rainfall structure in the area. Indeed, the observations can not be distinguished from the simulated time series. However, the simulated rainfall values tend to be slightly too high throughout the seasons, possibly due to the spatial correlation structure not completely appropriate for such a complex region. From the simulated rainfall sequences, seven growing season indices (including the onset and length of the growing season, proportion of rainy days and total precipitation during the growing season) are derived and their projected change investigated under a climate change scenario. There is little consensus between the 18 selected GCMs, regarding changes in growing season indices between two investigated periods in the 20th and 21st centuries. For the next couple of decades the dominant source of variation in the indices appears to be the natural rainfall variability. Such information should therefore be taken into account when planning adaptation and mitigation strategies. The research presented here emerges as the first comprehensive assessment of different climatic factors linked to southern Africa rainfall variability as well as the first attempt to evaluate the GLMs suitability for the generation of rainfall sequences for agricultural impact studies.

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Rogstad, Alix, Michael Crimmins, and Gregg Garfin. "Climate Change and Wildfire Impacts in Southwest Forests and Woodlands." College of Agriculture and Life Sciences, University of Arizona (Tucson, AZ), 2012. http://hdl.handle.net/10150/239605.

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Mahdu, Omchand. "The Impacts of Climate Change on Rice Production and Small Farmers' Adaptation: A Case of Guyana." Diss., Virginia Tech, 2019. http://hdl.handle.net/10919/89087.

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Prior research has concluded that climate change is having an overall negative impact on rice production worldwide. The vast majority of climate change impacts on rice production result from fluctuations in precipitation and temperature, which lead to flooding, water scarcity, and increases in insects and pests, diseases, and weeds. As a small developing country, Guyana is highly vulnerable to climate change despite its insignificant contribution to global warming. Guyana heavily relies on rice cultivation for food, employment, and export earnings. While generally increasing, rice yields have fluctuated over the last two decades. For example, in 2016, rice yields declined by 12.7 percent due to a drought. This dissertation explores the relationship between fluctuating yields and climate change, and how farmers are adapting. Of particular importance are the impacts of climate change on small farmers (those cultivating less than 4.45 hectares or 11 acres) and their ability to successfully adapt. Small farmers are especially vulnerable to a changing climate because they often lack the necessary knowledge, support, and resources to effectively respond and adapt. Given the large percentage of rice farmers engaging in small-scale production in Guyana, this study investigates the impacts of climate variability on rice production and the extent to which the production and productivity of small farmers are affected. It also identifies the coping strategies small farmers employ to combat the effects of climate change and the extent to which these strategies are successful. Given that climate change is expected to vary across different regions of the world, the first aim of this study is to show how the climate in Guyana has changed. At the country level, evidence from descriptive statistics, a linear trend model, and a two-sample t-test shows that minimum and maximum temperatures have increased over the last 111 years. The aggregate data is less clear on changes in precipitation over the last 111 years. However, analysis of farm-level data provides strong evidence of shifts in rainfall patterns. Among 189 small farmers interviewed, 182 (96.3%) perceived changes in rainfall patterns, 170 (89.9%) perceived changes in temperature, 169 (89.4%) perceived changes in extreme weather events, 185 (97.9%) perceived changes in insects and pests, 73 (38.6%) perceived changes in diseases, and 168 (88.9%) perceived changes in weeds. Changes in precipitation have included an increase in intensity and out of season rainfall, which has impacted harvesting due to poor dams, wet fields, and the lodging of plants. The primary responses farmers have adopted include adjusting planting dates based on water availability and the cultivation of different rice varieties. Changes in temperature have resulted in hotter days, accelerating the evaporation of water from fields. In response, farmers replenish water in their fields, when available. Excess rainfall and resulting flooding, drought, and heavy winds have been the primary extreme weather events observed. Excess rainfall and associated flooding submerges, uproots, and/or kills young plants. The lodging of plants due to heavy winds and flooding has been the main impact. In response to flooding, farmers have pumped water out of their fields. There is very little that farmers can do in response to heavy winds. The primary change in insects and pests reported by farmers has been an increase in paddy bug infestations, which cause damage to the grains resulting in lower quality and quantity at harvest. As a result, farmers are engaging in more preventative spraying. An increase in brown spot disease was also reported. Brown spots are primarily found on the leaves, damaging and/or stunting the growth of the plants by reducing the amount of food they manufacture through photosynthesis. Farmers have responded by engaging in preventative spraying and the rotation of fungicides. Increases in red rice and duckweed have been the major changes in weeds observed. Both weeds compete with rice for space, sunlight, nutrients, and water. Additionally, red rice reduces the quality and by extension the price farmers receive. Farmers are responding by spraying more herbicide and using a contact chemical to burn red rice. Multivariate analysis of farm-level data found that land tenure, tractor ownership, membership in an agricultural organization(s), secondary non-agricultural income, and farms located in regions two and four have positive correlations with annual yields. Perceived changes in rainfall, farm size, livestock ownership, participation in rice extension training, and household members help with rice farming were found to have negative correlations with annual yields. Policy recommendations to improve rice production and farmers' resilience include improving research and development capacity; tax exemption for agricultural inputs and equipment; improving extension services; improving the management of irrigation systems and water resources; enhanced access to credit, insurance, and subsidies; improving weather forecasting and climate monitoring; and improving the management of drainage infrastructure. The analytical framework used in this research produced a rich dataset and interesting results that are important to our understanding of farm-level impacts and responses to climate change. As such, it may prove useful for studying climate change impacts in other developing countries that have similar characteristics and face similar risks from climate change as Guyana.
Doctor of Philosophy
The vast majority of climate change impacts on rice production result from variations in rainfall and temperature that lead to flooding, water shortage, and increases in insects and pests, diseases, and weeds. Guyana is highly exposed to climate change. More importantly, the country relies heavily on rice farming for food, employment, and foreign income. Of particular importance are the impacts of climate change on small farmers (growing less than 4.45 hectares) and their ability to successfully adapt. Small farmers are especially helpless because they often lack the necessary knowledge, support, and resources to effectively respond and adapt. Given the large percentage of rice farmers engaged in small-scale production in Guyana, this study explores the impacts of climate variability on rice production and the extent to which the production and output of small farmers are affected. Analysis of farm-level data shows that changes in rainfall have included an increase in intensity and out of season rainfall which has affected harvesting due to poor farm-to market roads, wet fields, and lodging of plants. The main responses involved adjusting planting dates based on water availability and the cultivation of different rice varieties. Changes in temperature resulted in hotter days which increased the loss of water from the field. In response, farmers replenish water in their fields, when available. Excess rainfall and resulting flooding, drought, and heavy winds have been the main extreme weather events observed. Excess rainfall and associated flooding submerges, uproots, and/or kills young plants. The lodging of plants due to heavy winds and flooding has been the main impact. In response to flooding, farmers have pumped water out of their fields. There is very little that farmers can do in response to heavy winds. An increase in paddy bug infestations damaged the grains resulting in lower grain quality while an increase in red rice and duckweed increased the competition for space, sunlight, nutrients, and water. Farmers engaged in more defensive spraying and used a contact chemical to burn red rice.

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Shi, Ge. "Variability and change of the Indo-Pacific climate system and their impacts upon Australia rainfall." University of Southern Queensland, Faculty of Sciences, 2008. http://eprints.usq.edu.au/archive/00004784/.

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[Abstract]: Australia is one of the driest continents in the world, and over the past decades, severe drought has plagued most of the country. Water security is an important national issue. The ultimate water supply, rainfall, however, is one of the most variable ones in theworld and is complicated by the fact that it is affected by several remote oceanatmospheric teleconnection systems simultaneously, including the El Niño-SouthernOscillation, the Indian Ocean Dipole and Southern Hemisphere oceanic and atmospheric variability. These three systems sometimes conspire to produce a severe impact, whereas sometimes they offset each other to produce a mild influence. The recent severe watershortage has generated a surge of investments with strong regional applications. The present study focuses on areas and issues outside the scope of these regional studies,aiming to provide an Australia-wide assessment of future Australian rainfall under climate change. Firstly, we unravel a process of the Indo-Pacific oceanic teleconnection and examine its role in influencing variability of the Indian Ocean, and hence Australianrainfall variations. An examination of their contribution to the warming structure of the Indian Ocean is carried out. Secondly, we explore dynamics of North West Australianrainfall variability and mechanisms of a rainfall increase over the past decades, and benchmark climate models in terms of their ability to reproduce the observed variability and trends, focusing on the role of increasing northern hemispheric aerosols in the rainfallincrease. Thirdly, we provide a dynamical explanation to the common future of a fast Tasman Sea warming rate under climate change, and identify the impacts of suchwarming on Australian rainfall. Finally, we examine the relative importance of the three systems, in addition to Tasman Sea warming, in driving rainfall changes undergreenhouse conditions. This project contributes to no less than six peer-reviewed journal publications.

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Ndlala, Noluthando. "Remote sensing drought impacts on wetland vegetation productivity at the Soetendalsvlei in the Heuningnes Catchment, South Africa." University of Western Cape, 2021. http://hdl.handle.net/11394/8329.

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>Magister Scientiae - MSc
This work aimed at assessing the response of wetland vegetation productivity to the 2014-2017 climate-induced drought at the Soetendalsvlei wetland system in the Western Cape province of South Africa. To achieve this objective, firstly a literature review on the progress of remotely sensed data applications in assessing and monitoring wetland vegetation productivity was conducted. The review elaborates on the role of remote sensing in monitoring and assessing wetland vegetation productivity, with a detailed discussion of the climate change and variability impacts on wetland vegetation productivity. Accurate assessment results are produced when suitable processing techniques are selected as well as appropriate spatial and spectral resolution for extracting spectral information of wetland vegetation productivity. Secondly, wetland vegetation changes and productivity status was assessed using multi-temporal resolution Landsat series imagery and Normalized Difference Vegetation Index (NDVI) during the wet and dry seasons for the period between 2014 and 2018.

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Wohland, Jan [Verfasser], Dirk [Gutachter] Witthaut, Andreas [Gutachter] Schadschneider, and David [Gutachter] Brayshaw. "Impacts of climate variability and climate change on renewable power generation / Jan Wohland ; Gutachter: Dirk Witthaut, Andreas Schadschneider, David Brayshaw." Köln : Universitäts- und Stadtbibliothek Köln, 2019. http://d-nb.info/1193649420/34.

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Jones, Chris, and Melanie Lenart. "Rising Carbon Dioxide Levels and Forest Management (Climate Change and Variability in the Southwest Ecosystem Series)." College of Agriculture and Life Sciences, University of Arizona (Tucson, AZ), 2006. http://hdl.handle.net/10150/146951.

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4 pp.
Climate Change and Variability in Southwest Ecosystems Series
Several environmental factors are changing, including the global rise in atmospheric CO2 concentrations and global warming. These environmental changes portend needed changes in the future management of forests in the Southwestern U.S. Therefore, University of Arizona Extension Agents organized a Workshop in Sedona, AZ, in February, 2005, targeted at Southwest forest managers. This paper presents facts from one of the presentations at that workshop and summarizes what the direct effects of the increased CO2 concentrations are likely to be on future tree growth. It is expected that the growth of most trees will be stimulated by the higher CO2 concentrations but variations in response among species will alter competition among species. The fact sheet also speculates about what the implications may be for future forest management. This research benefits the forest industry, as well as the many consumers of forest products.

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Islam, Md Monirul. "Vulnerability and adaptation of fishing communities to the impacts of climate variability and change : insights from coastal Bangladesh." Thesis, University of Leeds, 2013. http://etheses.whiterose.ac.uk/5321/.

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Climate variability and change are predicted to impact on coastal and marine smallscale fisheries and dependent communities. They have been adapted to the normal range of climate variability and its impacts, but additional adaptation will be required to address the increased impacts of climate change. Migration is regarded as one strategy to adapt to these impacts but debates surround its successfulness. Fishing communities can adapt in many ways and migration is one example. However, limits and barriers can prevent adaptation being successful or reduce vulnerability. Studies on vulnerability, adaptation and limits and barriers to adaptation are therefore preconditions for the fishing communities to develop effective adaptation strategies to face climate variability and change. Despite considerable studies on the impact of climate change on aquatic ecosystems and fish stocks, the macro scale fishery-dependent economies and their people, and on vulnerability and adaptation in agricultural communities, there has been insufficient examination of the vulnerability and adaptation of small-scale fishing communities to climate variability and change. This thesis therefore assesses the vulnerability and adaptation to the impacts of climate variability and change, in three small-scale coastal fishing communities in Bangladesh. Using a mixed method approach, particular focus is given to the assessment of livelihood vulnerability, the investigation of the outcomes of climate induced migration, and the exploration of limits of and barriers to adaptation. Results highlight that the level of livelihood vulnerability not only differs between communities but also between different household groups within a community, depending on their level of exposure, sensitivity and adaptive capacity. Exposure to floods and cyclones; sensitivity (such as dependence on small-scale marine fisheries for livelihoods); and lack of adaptive capacity in terms of physical, natural and financial capital and diverse livelihood strategies construe livelihood vulnerability in different ways depending on the context. Results show that the most exposed community is not necessarily the most sensitive or least able to adapt because livelihood vulnerability is a result of combined but unequal influences of biophysical and socio-economic characteristics of communities and households. Within a fishing community, where households are similarly exposed, higher sensitivity and lower adaptive capacity combine to create higher vulnerability. Migration may be a viable strategy to respond to climate variability and change. Results show that migration has generated several positive outcomes for households that resettled. The resettled households are now less exposed to floods, sea level rise and land erosion than those who stayed behind. They have also more livelihood assets and better access to them. They enjoy higher incomes, better health, better access to water supply, health and educational services, technology and markets than the households who remained in their original settlement. The thesis also establishes that fishing communities face multiple limits and barriers to adaptation of fishing activities to cyclones, however. Limits include physical characteristics of climate and sea, such as higher frequency and duration of cyclones, and hidden sandbars. Barriers include technologically poor boats, inaccurate weather forecasts, poor radio signals, lack of access to credit, low incomes, underestimation of cyclone occurrence, coercion of fishermen by the boat owners and captains, lack of education, skills and livelihood alternatives, unfavourable credit schemes, lack of enforcement of fishing regulations and maritime laws, and lack of access to fish markets. These local and wider scale factors interact in complex ways and constrain completion of fishing trips, coping with cyclones at sea, safe return of boats from sea, timely responses to cyclones and livelihood diversification. Overall, this thesis contributes empirical evidence to current debates in the literature on climate change by enhancing an understanding of the characteristics and determinants of livelihood vulnerability, migration as an adaptation strategy and limits and barriers to the adaptation of fishing communities to climate variability and change. The findings of this thesis form the basis for further detailed research into the vulnerability and adaptation of small-scale fishing communities to climate variability and change. Based on the above findings, this thesis also provides some suggestions for reducing vulnerability and for developing effective adaptation strategies.

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Sikder, Abu Hena Mustafa Kamal. "Analyzing Spatial Variability of Social Preference for the Everglades Restoration in the Face of Climate Change." FIU Digital Commons, 2016. http://digitalcommons.fiu.edu/etd/2565.

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The South Florida Everglades is a unique ecosystem. Intensive water management in the system has facilitated agricultural, urban, and economic development. The Everglades offers a variety of ecosystem services (ES) to the people living in this region. Nevertheless, the ecosystem is under imminent threat of climate change, which would alter the way water is managed today and ultimately affect the ES offered by the system. On the other hand, substantial restoration is underway that aims to restore the Everglades closer to its historic condition. This research tried to map the public’s preference for Everglades restoration. Using a geocoded discrete-choice survey dataset, the study showed variation in the public’s preference by changing the levels of ES. Additionally, the general public’s attitude toward climate change risk to the Everglades and preference for mitigation were also assessed using the survey data.

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Hagerman, Shannon Marie. "Adapting conservation policy to the impacts of climate change : an integrated examination of ecological and social dimensions of change." Thesis, University of British Columbia, 2009. http://hdl.handle.net/2429/7903.

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Recognition of the impacts of climate change has prompted re-assessment of existing conservation policy frameworks (here thought of as collections of means and objectives that reflect values, beliefs and expectations of control). The concern is that changing temperature and precipitation regimes will alter an extensive range of biological processes and patterns. These system dynamics are at odds with long-established conservation policies that are predicated on assumptions of stable biodiversity targets (e.g. species or ecosystems), and that seek to protect these targets by means of static protected areas. Efforts to address this challenge have so far originated from the fields of ecology and biogeography and include the core adaptive strategies of expanding protected areas and implementing migration corridors. The purpose of this research was to reach beyond these disciplines to integrate across a set of ecological and social insights to develop a more holistic understanding of challenge of adapting conservation policy to the impacts of climate change. Two overarching questions guided this research: 1) do the impacts of climate change necessitate a different set of means, objectives and expectations than are indicated by current conservation adaptation proposals (i.e. proposals that include new protected areas and migration corridors as the primary adaptive strategy); and 2) if there is evidence that this is so, what are the barriers to implementing a policy framework with new means, objectives and expectations? Using a combination of case study, expert elicitation, and ethnographic methods, the results of this thesis provide empirical evidence that the impacts of climate change are seen by many experts to implicate the need for changes in conservation policy that include consideration of interventions such facilitating species distributions through disturbance, assisted migration, revised objectives, and triage-like priority setting. Yet simultaneously there is evidence of a public precautionary ambivalence towards these alternative elements of a potentially new policy framework, combined with durable more preservationist (less engineering) conservation values. It is contended that these value-based commitments have in part, shaped the adaptive response so far. Combined, these results highlight that policy adaptation within “science-based” conservation is a tangle of social dynamics, including durable preservationist-type values and related resistance to anticipated difficult trade-offs implicit in a more transformative decision framework.

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Kuriakose, Jaise. "The resilience of low carbon electricity provision to climate change impacts : the role of smart grids." Thesis, University of Manchester, 2016. https://www.research.manchester.ac.uk/portal/en/theses/the-resilience-of-low-carbon-electricity-provision-to-climate-change-impacts-the-role-of-smart-grids(c139ce36-d73c-4d8b-913e-f66826496405).html.

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The UK’s decarbonisation strategy to increasingly electrify heating and transport will change the demand requirement on the electricity system. Additionally, under a climate change future, it is projected that the decarbonised grid will need to be able to operate under higher average temperatures in the UK, increasing the need for comfort cooling during summer and leading to additional electricity demand. These new demands will result in greater variation between minimum and peak demand as well as a significant increase in overall demand. Concurrently, supply-side decarbonisation programmes may lead to more intermittent renewables such as wind, PV, tidal and wave, elevating variability in electricity generation. Coupled with the anticipated higher variation in demand this brings on several challenges in operating the electricity grid. In order to characterise these challenges this research develops a bespoke electricity dispatch model which builds on hourly models of demand and generation. The hourly demand profiles are based on a high electrification of heating, transport and cooling coupled with future temperatures premised on the UKCP09 high emission scenario climate projections. The demand profiles show a significant increase in peak demand by 2050 reaching 194 GW, mainly due to summer cooling loads which contribute 70% of the demand. The cumulative CO2 emissions budgets of the GB power sector that are consistent with avoiding global climate change to 2°C are used to develop two low carbon generation scenarios distinguished by the amount of intermittent renewable generation technologies. The dispatch model tests the capability of generation scenarios with the use of hourly generation models in meeting future demand profiles out to 2050.The outputs from dispatch model indicate that there are shortages and excesses of generation relative to demand from 2030 onwards. The variability analysis outlines low and high generation periods from intermittent technologies along with the pace at which intermittent generation increases or decreases within an hour. The characterisation of variability analysis reveals the type of reserve capacity or smart solutions that are required to maintain the security of electricity supply. The solutions that could address the challenges quantified from the model outputs in operating a decarbonised GB electricity grid are explored using expert interviews. The analysis of the stakeholder interviews suggests smart grid solutions that include technologies as well as changes in operational procedures in order to enhance the operational resilience of the grid. Active Network Management through monitoring and control, demand management, storage systems and interconnectors are proposed to address challenges arising from varying demand and generation variability.

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Mbungu, Winfred Baptist. "Impacts of Land Use and Land Cover Changes, and Climate Variability on Hydrology and Soil Erosion in the Upper Ruvu Watershed, Tanzania." Diss., Virginia Tech, 2017. http://hdl.handle.net/10919/83863.

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Land alterations including deforestation, unsustainable land management practices and an increase in cultivated areas have occurred in the Upper Ruvu watershed in recent decades threatening water and natural resources. This study, which used a combination of remote sensing techniques, field experiments, watershed monitoring, and modeling was designed to investigate impacts of environmental changes on hydrology and soil erosion. The objectives were to: map the extent of land use and land cover change and its influence on soil erosion; correlate the contribution of climate variability and human activities to the changes in hydrology at headwater and watershed scales; estimate surface runoff, sediments and Curve Number at plot scale, and model streamflow responses to changes in land use and land cover using the SWAT watershed model. Results indicate that areas covered by forest decreased from 17% in 1991 to 4% of the total watershed area in 2015. However, areas covered by cropland increased from 14% to 30% of the total watershed area from 1991 to 2015, respectively. Further, results indicate that site characteristics affect runoff and sediment yield as higher soil loss was estimated from cropland with a mean of 28.4 tha-1 in 2015 from 19.8 tha-1 in 1991. Results from monitoring show high sediment loads were from the most disturbed watersheds, compared to Mbezi. Analysis of trends for the long term records at the watershed showed that rainfall had significant decreasing trends. At annual scale, climate variability contributed 46% and human activities contributed 54% of the changes in streamflow. Results from the rainfall simulation experiments show upland rice had higher runoff (48 mmh-1) and soil loss (94 gm-2) compared to grassland and forest. Results from the model outputs showed that average streamflow decreased by 13% between 1991 and 2015. Average peak flows increased by 5% and 12% for 2000 and 2015, respectively compared to the baseline. Land alterations had impacts on surface runoff which increased by 75% and baseflow decreased by 66% in 2015 from the baseline. These results highlight the main areas of changes and provide quantitative information to decision makers for sustainable land and water resources planning and management.
Ph. D.

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Rahmani, Vahid. "Assessing impacts of climate change on Kansas water resources: rainfall trends and risk analysis of water control structures." Diss., Kansas State University, 2014. http://hdl.handle.net/2097/18342.

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Doctor of Philosophy
Department of Biological & Agricultural Engineering
Stacy L. Hutchinson
Precipitation impacts hydrologic structures, agricultural production, water resources management, and recreational activities, all of which significantly affect a state’s economy. Water control structure design is based on the maximum runoff rate resulting from storms with a specific return period and duration. The Rainfall Frequency Atlas (National Weather Service Technical Paper 40, 1961) (TP-40) provided statistical rainfall analysis as the basis for hydrologic structure design until the information was updated for Kansas in February 2013 (National Oceanic and Atmospheric Administration Atlas 14, volume 8) (Atlas-14). With growing concern about the effects of global climate change and predictions of more precipitation and extreme weather events, it is necessary to explore rainfall distribution patterns using the most current and complete data available. In this work, the changes in rainfall patterns were studied using the daily rainfall data from 23 stations in Kansas and 15 stations from adjacent states with daily rainfall data of 1890 through 2012. Analysis showed an increase in extreme precipitation events in Kansas with increase in magnitude from the northwest to southeast part of the state. A comparison of results of the TP-40 analysis to period 1980–2009, showed that approximately 84% of the state had an increase in short-term rainfall event magnitudes. In addition, trend analyzes on the total annual rainfall indicated a gradual increase at 21 out of 23 stations, including eight statistically significant trends. A change-point analysis detected a significant sudden change at twelve stations as early as 1940 and as recently as 1980. The increasing trend, particularly after the significant change-points, is useful in updating water management plans and can assist with agricultural production decisions such as crop selection and new plant variety development. A comparison between 10-yr, 24-hr storms from TP-40 and Atlas-14 indicated a change of -12% to 5% in Kansas. However, the number of exceedances from the 10-yr, 1-, 2-, 3-, 4-, 7-, and 10-day storms demonstrated a tendency towards more exceedances, particularly in the last five decades. Results of this study are useful for hydrologic structure design and water resources management in order to prevent accepting additional risk of failure because of the current changing climate.

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Nunfam, Victor Fannam. "Social impacts of climate change and occupational heat stress and adaptation strategies of mining workers in Ghana." Thesis, Edith Cowan University, Research Online, Perth, Western Australia, 2019. https://ro.ecu.edu.au/theses/2273.

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Excessive heat exposure due to rising temperatures associated with climate change adversely affects workers’ health, safety, productivity, and psychosocial well-being in occupational settings. In the hot and tropical regions of developing countries, long hours of physically demanding work, coupled with inadequate adaptation policies to climate change, increases the occurrence of heat-related illnesses and injuries, and contributes to the loss of productive capacity, poor decision making, and other negative effects on the social well-being of workers. Based on the theories of social impact assessment, risk assessment, adaptation and resilience planning, this study assesses the social impacts of climate change and occupational heat stress and adaptation strategies of mining workers in Ghana, and thus fills a significant gap in the existing literature. Guided by the pragmatists’ research philosophical paradigm, this study adopted the convergent mixed methods approach by utilising data obtained from four temperature and humidity data loggers, 346 surveys of mining workers, two focus groups and three in-depth interviews. The quantitative data was processed with Microsoft Excel 2016, XLSTAT 2019, and analysed using Statistical Product and Service Solutions (SPSS) version 25 while the qualitative data was processed utilising NVivo version 11 and thematically analysed. The findings suggest that the use of convergent mixed methods showed adequate corroboration and complementarity between the qualitative and quantitative data and helped to obtain credible data relevant for policy decisions on heat stress management, workplace health and safety, and adaptation strategies. Supervisors’ climate change risks perception was adequate, workplace heat exposure risks concerns were moderate and their views of workers’ heat stress experiences were heat-related illness and minor injuries. The differences in supervisors’ climate change risk perceptions and occupational heat stress risk experiences across job experience and adaptation strategies across educational status were significant (p<0.05). Workers’ concerns about climate change effects and workplace heat exposure risks; heat-related morbidities experienced by workers; and their use of heat stress prevention measures significantly differed between Small-Scale Mining (SSM) and Large-Scale Mining (LSM) (p<0.001). The disparity in heat exposure risk factors across workers’ gender, education level, workload, work hours, physical work exertion, and proximity to heat sources was significant (p<0.05). Thermal assessments demonstrated that workers were exposed to high ambient heat conditions that raise their heat stress risk. Workers’ adaptation strategies, social protection measures, and barriers to adaptation strategies differed significantly across the type of mining activity (p<0.001). Based on the seven publications related to the social impacts of climate change and occupational heat stress and adaptation strategies of mining workers, this study recommends that there needs to be a concerted global effort at providing adequate and effective heat exposure and adaptation policies to promote workers’ health and safety, productive capacity and psychosocial well-being; to reduce their vulnerability to heat stress, improve their adaptive capacity and resilience; and enlighten policy decisions and enforcement in the mining industry.

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Dayon, Gildas. "Evolution du cycle hydrologique continental en France au cours des prochaines décennies." Thesis, Toulouse 3, 2015. http://www.theses.fr/2015TOU30252/document.

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L'étude des impacts du changement climatique demande souvent de mettre en place de longues chaînes de modélisation. Du modèle qui servira à estimer les concentrations futures en gaz à effet de serre jusqu'au modèle d'impact. Tout au long de cette chaîne de modélisation, les sources d'incertitudes s'accumulent et compliquent l'exploitation des résultats pour l'élaboration de stratégies d'adaptation. Il est proposé ici d'évaluer les impacts du changement climatique sur le cycle hydrologique en France ainsi que les incertitudes qui y sont associées. La contribution de chacune des sources d'incertitudes n'est pas abordée, principalement celle associée aux scénarios d'émission de gaz à effet de serre, aux modèles climatiques et à la variabilité interne. Nous proposons dans ce travail une approche pour évaluer la transférabilité dans un climat futur de la méthode statistique de régionalisation des simulations climatiques. La vérification de l'hypothèse de transférabilité effectuée est l'une des principales sources d'incertitudes des méthodes statistiques de régionalisation. L'évaluation proposée ici s'appuie sur l'utilisation de modèles régionaux, dans un cadre dit de modèle parfait, et permet de montrer que l'utilisation de certain prédicteurs s'avèrent utile à assurer la transférabilité de la méthode de régionalisation dans un climat futur. Cette approche proposée pour une méthode de désagrégation statistique est également applicable à des méthodes de correction des biais des modèles régionaux. Les récentes réanalyses atmosphériques sur l'ensemble du XXème siècle, régionalisées avec la méthode développée dans ce travail, et associées aux observations de température et précipitations permettent de caractériser le cycle hydrologique en France. Elles permettent notamment de montrer que la variabilité multi-décennale des débits observés pendant le XXème siècle est généralisée à l'ensemble du pays et est liée à la variabilité des conditions atmosphériques. Cette variabilité multi-décennale des débits est généralement plus faible dans les simulations hydrologiques réalisées avec les simulations historiques des modèles climatiques. Les projections climatiques ont été régionalisées avec la méthode développée dans ce travail. La température sur l'ensemble du pays, en moyenne sur les modèles climatiques, augmente jusqu'à 3,5°C en hiver et 6,5°C en été d'ici la fin du siècle. Les précipitations vont diminuer sur l'ensemble du pays en été, de presque moitié sur le sud du pays pour le scénario le plus sévère. En hiver, elles augmentent sur la moitié nord du pays et diminuent légèrement sur la partie sud. Dès les prochaines décennies, la diminution des précipitations est importante en été, l'évolution est moins marquée pour les autres saisons. Enfin, les résultats des projections hydrologiques réalisées avec un modèle hydrologique et un ensemble de modèles climatiques sont présentés pour les prochaines décennies et également pour la fin du XXIème siècle. Sur la Seine, les résultats sont différents en hiver de ceux présentés dans de précédentes études. Ici, les précipitations et les débits augmentent en hiver et diminuent en été sur ce bassin versant. Ailleurs en France, les résultats convergent avec les études précédentes, à savoir une augmentation de l'évapotranspiration, une diminution généralisée des débits et un assèchement des sols. L'incertitude due aux modèles climatiques et à la variabilité interne sur les changements relatifs de débits augmente systématiquement pendant le XXIème siècle, jusqu'à atteindre plus de 20% en hiver pour le scénario le plus sévère. Dans les prochaines décennies, l'incertitude due uniquement à la variabilité interne sur les changements de débits est aussi forte que l'incertitude due aux modèles climatiques et à la variabilité interne. Dès les prochaines décennies, les changements de débits annuels sont plus forts sur la Loire, la Garonne et le Rhône que les changements maximaux observés pendant le XXème siècle
The assessment of the impact of climate change often requires to set up long chains of modeling, from the model to estimate the future concentration of greenhouse gases to the impact model. Throughout the modeling chain, sources of uncertainty accumulate making the exploitation of results for the development of adaptation strategies difficult. It is proposed here to assess impacts of climate change on the hydrological cycle over France and associated uncertainties. The contribution of each sources of uncertainty is not addressed, mainly that associated with greenhouse gases emission scenario, climate models and internal variability. In the context of impacts of climate change on the hydrological cycle over France, it is possible to ask what is the contribution of each sources of uncertainty to the total uncertainty associated with mean changes. Is it possible to reduce, and if so how, the contribution of one source or another ? We propose in this work an approach to assess the transferability in the future climate of a statistical method to downscale climate simulations. The transferability assumption is one the main sources of uncertainty in statistical downscaling method. The assessment suggested here relies on the use of regional climate models, in a perfect model framework, and shows that some predictors are useful to ensure the transferability of the downscaling method in the future climate. This framework, proposed for a statistical downscaling method, is also applicable to bias correction methods in regional climate models. Recent atmospheric reanalyses of the 20th century are downscaled with the method developed in this work, associated with observations of temperature and precipitation. The hydrological cycle over France is characterized with these reconstructions. We show that the multi-decadal variability of observed streamflows during the 20th century is generalized to the whole country and is partly due to atmospheric variability. This multi-decadal variability of streamflows is generally weaker in hydrological simulations done with historical simulations from climate models. The climate projections have been downscaled with the method developed in this work. The temperature on the country, on average over climate models, could increased by 3,5°C in winter and 6,5°C in summer in the course of this century. Precipitations will decrease all over the country in summer, nearly by half on southern part of France for the most severe scenario. In winter, precipitations will increase in the northern part of the country and will decrease slightly in the southern part. In the next few decades, the decrease in precipitation is important in summer, and changes are less pronounced for other seasons. Results of hydrological projections done with one hydrological model and an ensemble of climate models are presented for the coming decades and for the end of the century. On the Seine river, results slightly differ in winter from those presented in previous studies. Here, precipitations and streamflow increase in winter and decrease in summer on that river basin. Elsewhere in France, results are consistent with previous studies, namely an increase in evapotranspiration, a decrease in streamflow and much drier soil. The uncertainty due to both climate models and internal variability on relative changes in streamflows always increase during the 21st century, to over 20% in winter for the most severe scenario. In the coming decades, the uncertainty due to internal variability only on streamflow changes is as strong as the uncertainty due to both climate models and internal variability. In the coming decades, annual streamflow changes of the Loire, Garonne and Rhône rivers are stronger than the maximum changes observed during the 20th century

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Makame, Makame Omar. "Vulnerability and adaptation of Zanzibar east coast communities to climate variability and change and other interacting stressors." Thesis, Rhodes University, 2014. http://hdl.handle.net/10962/d1011895.

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Climate variability and change as well as sea level rise poses significant challenges to livelihoods, water and food security in small island developing states (SIDSs) including the Zanzibar Islands. Thus, without planned strategic adaptation, the future projected changes in climate and sea level will intensify the vulnerability of these sensitive areas. This thesis is based on research conducted in two sites located in the north eastern parts of each island, namely Kiuyu Mbuyuni, Pemba Island and Matemwe, Unguja Island. The research focused firstly on assessing the vulnerability of these two coastal communities to climate variability and change and other stressors. This included investigation of (1) the perceptions of fishers, farmers and seaweed farmers regarding climate stressors and shocks and associated risks and impacts, (2) existing and possible future water and food security issues, and (3) household's access to important livelihood assets. This was followed by an exploration of the coping and adaptive responses of farmers, fishers and seaweed farmers to perceived shocks and stresses and some of the barriers to these responses. Lastly, an analysis of the implications of the findings for achieving sustainable coastal livelihoods and a resilient coastal community was undertaken. The general picture that emerges is that local people along the east coasts of both islands are already vulnerable to a wide range of stressors. Although variability in rainfall is not a new phenomenon in these areas, increasing frequency of dry spells and coastal floods resulting from the influence of El Niño and La Niña events exert enormous pressures on local activities (fishing, farming and seaweed farming) which are the crux of the local economy. The main argument of the study is that the nature and characteristics of these activities are the main source of sensitivity amongst these communities and this creates high levels of vulnerability to climate shocks and trends. This vulnerability is evidenced by the reoccurrence of localised food shortages and the observed food and water insecurity. The study found that food insecurity is a result of unreliable rainfall, drought and seasonality changes. These interacted with other contextual factors such as poor soil, low purchasing power and the lack of livelihood diversification options. In addition to exposure to these almost unavoidable risks from climate variability, the vulnerability of the local communities along the east coasts is also influenced by the low level of capital stocks and limited access to the assets that are important for coping and adaptation. Despite this, some households managed to overcome barriers and adapt in various ways both within the three main livelihood sectors (fishing, farming and seaweed farming) as well as through adopting options outside these sectors resulting in diversification of the livelihood portfolio. However, the study found that most of the strategies opted for by fishers, farmers and seaweed farmers were mainly spontaneous. Few planned adaptation measures supported by state authorities were observed across the sites, with the exception of the provision of motorised boats which were specifically meant to increase physical assets amongst fishers, reduce pressure in the marine conservation areas and prevent overfishing in-shore. Furthermore, numerous strategies that people adopted were discontinued when further barriers were encountered. Interestingly, some of the barriers that prevented households adapting were the same ones that forced households that had responded to abandon their adaptations. To increase resilience amongst east coast communities to current and future predicted changes in climate and sea level, the study argues that traditional livelihood activities (fishing, farming and seaweed farming) need to be better supported, and access to a range of livelihood assets improved. This may be achieved through increased access to local sources of water and facilitation of rainwater harvesting, expanding the livelihood options available to people and increasing climate change awareness, and access to sources of credit.

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Emrich, Merle. "International biopolitics and “climate refugees” as bare life. A Critical Discourse Analysis of how the UN’s framing of “climate refugees” impacts climate related global humanitarian migration and refugee governance." Thesis, Malmö universitet, Fakulteten för kultur och samhälle (KS), 2020. http://urn.kb.se/resolve?urn=urn:nbn:se:mau:diva-23429.

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This thesis investigates how the United Nations’ (UN) framing of “climate refugees” impacts global humanitarian migration and refugee governance in the context of anthropogenic climate change in which border zones become spaces of biopolitical decision making which impacts both governance strategies and International Relations as an academic field. It argues from a poststructuralist perspective that the UN’s discourse centred around climate change related human movement, the issue of “climate refugees” is downplayed, and “climate refugees” become bare life while their claims to legal protection are delegitimised. Thus, despite the concept of “climate refugees” becoming increasingly important in the Anthropocene, the UN’s discourse has remained vastly unchanged since McNamara’s analysis of it in 2007. The UN’s governance related discourse and reasoning concerning “climate refugees” and (humanitarian) global governance is explored through a Critical Discourse Analysis that examines a set of official UN documents which are relevant to the issue of forced human movement in the context of anthropogenic climate change.

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Danso, Isaac [Verfasser]. "Soil and water conservation technologies in the West African Sudan Savanna:Cropping systems options to address variability of crop yields and impacts of climate change / Isaac Danso." Bonn : Universitäts- und Landesbibliothek Bonn, 2015. http://d-nb.info/1080591680/34.

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Pickering, Evelyn Rose. "The Social Construction of Water in Dominica and How it has Influenced Use and Exportation." Thesis, The University of Arizona, 2014. http://hdl.handle.net/10150/338920.

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Dominica has been recognized for its landscape containing hundreds of rivers and receiving high rainfall, and "our water belongs to the world," or so says many Dominican citizens, and their government. A schism exists in the understanding of the water resources of Dominica. Local perceptions are in conflict with regional climate change data. Where climate change research has found Dominica to be high risk for water quality and quantity, locals maintain the mindset that there is an overabundance of the resource. Local epistemologies influence governmental water management practices, which presently focus on exportation of the resource. In efforts of economic development, while trusting that there is a surplus of water, Dominica leases billions of gallons of water each year to foreign companies. A popular conception on the island is that there is an abundance of water, and therefore, it should be shared globally. This unique social construction of Dominican water has been a foundation leading to the sale of billions of gallons of fresh water to international corporations. However, the bulk exportation of water is occurring in the context of climate change, and thus, the availability of water will be impacted by changes in annual rainfall, sea level rise, increased temperatures, and more severe hurricanes. The purpose of this study is to gain a better understanding of how the social understanding of water in Dominica was constructed, and what this means in relation to resource exportation and climate change. This research-based paper explores Dominican perceptions of water abundance and sustainability.

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Saemian, Sina. "ADAPTATION STRATEGIES TO IMPACTS OF CLIMATE CHANGE AND VARIABILITY ON TEHRAN WATER SUPPLY IN 2021 : AN APPLICATION OF A DECISION SUPPORT SYSTEM (DSS) TO COMPARE ADAPTATION STRATEGIES." Thesis, Uppsala universitet, Institutionen för geovetenskaper, 2013. http://urn.kb.se/resolve?urn=urn:nbn:se:uu:diva-193998.

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In this thesis, the decision analysis process of investigating the best optimal strategy for Tehran water management in 2021 is described. Such process is normally divided into four steps including: structuring the problem; identifying feasible strategies, their impact and uncertainty; quantifying preferences; and evaluation of countermeasures and sensitivity analysis. Here, in order to structure the problem, the characteristics of Tehran with respect to water issues and its history of water management are reviewed. The state of surface waters and ground waters and a description of Tehran plan for waste water treatment are given, the most significant constraints of Tehran water sector are classified and the challenges of climate change and variability are explained. The feasible adaptation strategies are designed subsequently based on that classification, data extracted from a survey and a number of interviews with water officials and managers and ordinary citizens in Tehran. Each strategy contains a series of separate measures with different weights. The phase of quantifying preferences and elucidating utility functions is conducted based on the data available from previous studies and also the current survey. The measures include: installing water saving devices, awareness raising to change citizens’ water consumption pattern, adding new sources of surface water, investing on waste water utilization, migration control and repairing water distribution network.Different combinations of these measures provide different possibilities for formulating adaptation strategies. We compare two more discussed adaptation strategies of the spectrum of strategies; one is inclined toward exploiting more water resources while the other one is more focused on demand management. The former is mainly supported by water officials and the latter advocated by water experts we interviewed. The criteria of comparison are social acceptability, economic feasibility, time-efficiency and environmental tenability. By considering the uncertainty attributed to the criteria weights, the WEB-HIPRE DSS analysis shows that the demand-oriented strategy is the optimal one in most cases, however, if time-efficiency and/or economic feasibility gain very high significance, the strategy of water officials wins over that of experts.

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Hansson, Robin, and Elena Mokeeva. "Securing resilience to climate change impacts in coastal communities through an environmental justice perspective: A case study of Mangunharjo, Semarang, Indonesia." Thesis, KTH, Miljöstrategisk analys (fms), 2015. http://urn.kb.se/resolve?urn=urn:nbn:se:kth:diva-175468.

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Climate change impacts have been shown to increase the social, economic and ecological vulnerabilities of poor groups in coastal communities of Asian countries. Mangunharjo village in Semarang city, Indonesia, has been identified as vulnerable to sea level rise, coastal erosion, tidal inundation and flooding, and the well-being of residents is threatened due to loss of livelihoods. In order to secure their future, the community has to enhance its resilience to climate change impacts, however, additional factors are undermining thepotential of a resilient and prosperous village. As resilience theory carried out in practice could negatively affect already marginalized people if trade-offs are not identified, a complementing theory is needed. This study develops a novel joint framework of resilience theory and environmental justice for analyzing the potential of enhancin gthe community’s resilience. It also explores what is needed for the village in order to increase its resilience. The framework revealed to be successful in identifying root problems and highlighted deficiencies in current resilience strategies. Moreover, the incorporation of environmental justice broadened the perspective of what could weaken the resilience ofthe village. Hence, an environmental justice perspective complements resilience theory as it identifies potential trade-offs and analyzes whose resilience is enhanced. The framework is argued to be a useful tool to secure resilience of a social-ecological system of various scales, however, further research is needed onthe optimal linkages of the two theories.

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Menke, Valerie [Verfasser], and Gerhard [Akademischer Betreuer] Schmiedl. "Impacts of short-term climate change and anthropogenic activity on marine ecosystem variability and biogeochemical processes in the Gulf of Taranto (central Mediterranean Sea) / Valerie Menke ; Betreuer: Gerhard Schmiedl." Hamburg : Staats- und Universitätsbibliothek Hamburg, 2018. http://d-nb.info/1156462053/34.

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Assfaw, Tesfamicheal Wossen [Verfasser], and Thomas [Akademischer Betreuer] Berger. "Climate variability, social capital and food security in Sub-Saharan Africa : household level assessment of potential impacts and adaptation options / Tesfamicheal Wossen Assfaw ; Betreuer: Thomas Berger." Hohenheim : Kommunikations-, Informations- und Medienzentrum der Universität Hohenheim, 2018. http://d-nb.info/1156326451/34.

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Wossen, Tesfamicheal Assfaw [Verfasser], and Thomas [Akademischer Betreuer] Berger. "Climate variability, social capital and food security in Sub-Saharan Africa : household level assessment of potential impacts and adaptation options / Tesfamicheal Wossen Assfaw ; Betreuer: Thomas Berger." Hohenheim : Kommunikations-, Informations- und Medienzentrum der Universität Hohenheim, 2018. http://nbn-resolving.de/urn:nbn:de:bsz:100-opus-11645.

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Erazo, Bolivar. "Representing past and future hydro-climatic variability over multi-decadal periods in poorly-gauged regions : the case of Ecuador." Thesis, Toulouse 3, 2020. http://www.theses.fr/2020TOU30119.

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Cette thèse évalue des méthodes pour représenter la variabilité spatio-temporelle hydro-climatique passée et future dans les régions peu jaugées. Elle propose une procédure complète et reproductible appliquée à l'Équateur et s'appuyant sur des données hydro-climatiques observées et simulées en vue de représenter la variabilité passée et de projeter l'impact potentiel des changements climatiques sur les écoulements à la fin du 21ème siècle. Un état de l'art a permis d'identifier plusieurs techniques qui ont été intégrées dans une chaîne méthodologique pour obtenir des séries spatio-temporelles continues de température, de précipitation et de débit sur les périodes multi-décennales passées et futures. Trois chapitres centraux sont consacrés à cet objectif selon les thèmes suivants : (1) régionalisation de la température et des précipitations à partir de mesures in situ en comparant des techniques déterministes et géostatistiques avec une prise en compte de corrections orographiques; (2) reconstruction du débit dans différents bassins versants à l'aide de modèles hydrologiques conceptuels utilisés selon une approche multimodèle et multiparamétrique; et (3) projections hydro-climatiques basées sur des simulations de modèles climatiques sous contrainte d'un scénario marqué d'émission de gaz à effet de serre. La régionalisation du climat a révélé l'importance de caler les paramètres de spatialisation et d'évaluer les champs interpolés par rapport à des stations ponctuelles indépendantes et via des analyses de sensibilité hydrologique. La reconstruction des débits a été possible grâce aux simulations combinées de trois modèles hydrologiques évalués dans des conditions climatiques contrastées, et forcés par les variables climatiques régionalisées. Des simulations de changements hydro-climatiques à moyen terme (2040-2070) et à long terme (2070-2100) ont ensuite été analysées avec des intervalles de confiance de 95 %, en utilisant des scénarios de neuf modèles climatiques et en transférant les paramètres hydrologiques calibrés pour la reconstruction des débits. L'analyse de la variabilité hydro-climatique montre une légère augmentation des températures sur la période 1985-2015, tandis que la variabilité des précipitations est liée aux principaux modes des phases El Niño et La Niña à l'échelle inter-annuelle et au déplacement de la zone de convergence inter-tropicale (ZCIT) à l'échelle saisonnière. Une augmentation générale de la température (+4,4 °C) et des précipitations (+17 %) est attendue d'ici à la fin du 21ème siècle, ce qui pourrait entraîner une augmentation de +5 % à +71 % du débit annuel moyen selon les bassins versants. Ces résultats sont discutés en termes d'importance pour la gestion de l'eau, avant de suggérer de futures recherches hydrologiques telles que la régionalisation du débit des cours d'eau, une meilleure quantification des incertitudes et une évaluation de la capacité à satisfaire les futurs besoins en eau
This thesis investigates methods to represent the past and future hydro-climatic variability in space and over time in poorly-gauged regions. It proposes a complete and reproducible procedure applied to the continental Ecuador to deal with observed and simulated hydro-climatic data in order to represent past variability and project the potential impact of climate change on water resources by the end of the 21st century. Up-to-date techniques were identified in a literature review and were integrated in a chain protocol to obtain continuous space-time series of air temperature, precipitation and streamflow over past and future multi-decadal periods. Three central chapters are dedicated to this objective according to the following topics: (1) regionalization of air temperature and precipitation from in situ measurements by comparing deterministic and geostatistical techniques including orographic corrections; (2) streamflow reconstruction in various catchments using conceptual hydrological models in a multi-model, multi-parameter approach; and (3) hydro-climate projections using climate model simulations under a high range emission scenario. Climate regionalization revealed the importance of calibrating parameters and of assessing interpolated fields against independent gauges and via hydrological sensitivity analyses. Streamflow reconstruction was possible with the regionalized climate inputs and the combined simulations of three hydrological models evaluated in contrasting climate conditions. Future medium term (2040-2070) and long term (2070-2100) hydro-climatic changes were analysed with confidence intervals of 95% using scenarios from nine climate models and transferring the model parameters calibrated for streamflow reconstruction. Analysis of hydro-climatic variability over the period 1985-2015 showed a slight increase in temperature, while precipitation variability was linked to the main modes of El Niño and La Niña phases at inter-annual scale and to the displacement of the inter-tropical convergence zone (ITCZ) at seasonal scale. Under climate change, a general increase in temperature (+4.4 °C) and precipitation (+17%) is expected by the end of the 21st century, which could lead to between +5% and 71% increase in mean annual streamflow depending on the catchments. These results are discussed in terms of significance for water management before suggesting future hydrological research such as regionalizing streamflow, better quantifying uncertainties and assessing the capacity to meet future water requirements

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Rack, Mireille. "Sustainability assessment of biochar : evaluating the potential environmental, economic and social impacts of the production and application of biochar in Europe as an option for climate change mitigation." Thesis, Imperial College London, 2017. http://hdl.handle.net/10044/1/58339.

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Sustainable development and climate change are at the forefront of today’s political agendas, as signified by the 2016 Paris Agreement and the 2015 United Nations’ Sustainable Development Goals. Carbon Dioxide Removal (CDR) technologies are being investigated for their contribution to reducing atmospheric greenhouse gas levels. The PhD assesses the potential of biochar systems as a sustainable CDR technology for climate change mitigation at a European scale. The potential sustainability impacts of biochar production and land application are evaluated by applying life cycle approaches to analyse the environmental, economic and social impacts within the overarching Life Cycle Sustainability Assessment (LCSA) framework. Scenario modelling is incorporated to estimate feedstock potentials and the scale of biochar production within Europe, as well as the corresponding levels of carbon sequestration. The research results indicate that gasification biochar systems have potential as CDR technologies, though the uncertainty regarding biochar’s stable carbon fraction remains a significant knowledge gap. The use of ‘wastes’ as the input material is more likely to reduce potential negative impacts in all three sustainability components. Though overall, the current economic climate limits the feasibility of sustainable biochar systems. The results are sensitive to the modelling approach, especially the incorporation of ‘consequential’ elements, which was shown to significantly benefit the outcomes of the environmental and economic assessments. The scenario modelling outputs suggest that large-scale implementation of biochar systems within Europe can contribute an important share of the EU emission reduction targets. However, to incentivise the uptake of biochar and/or to generate policy support, further certainty and evidence of biochar’s impacts following land application is needed. Overall, a single-issue focus is no longer applicable in today’s policy climate. It is important to assess all three pillars of sustainability when evaluating whether a product system/process is capable of contributing to sustainable development. The novel LCSA framework shows potential to assist with such assessments at the micro-level.

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Grochocki, Julian Lucian. "Late Holocene Environmental Variability as Recorded in the Sediment of a Northeastern Ohio Kettle Lake." University of Akron / OhioLINK, 2017. http://rave.ohiolink.edu/etdc/view?acc_num=akron1491558782637496.

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Qasmi, Saïd. "Sensibilité du climat européen à la variabilité multidécennale de l'Atlantique Nord." Thesis, Toulouse 3, 2018. http://www.theses.fr/2018TOU30367.

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La tendance au réchauffement d'origine anthropique observée au cours du XXè siècle en Europe est ponctuée par des fluctuations expliquées en partie par la variabilité interne du climat. Les mécanismes physiques entre la Variabilité Atlantique Multidécennale (AMV), dont la composante interne module une partie de la variabilité atmosphérique, et le climat européen sont étudiés dans cette thèse. Une étude des modèles climatiques montre une grande diversité dans la simulation de la téléconnexion entre l'AMV et la température estivale en Europe. La sous-estimation moyenne de son intensité par rapport aux observations contribue notamment à expliquer les incertitudes qui entachent les prévisions décennales du climat. Des expériences numériques utilisées pour isoler les mécanismes d'influence de l'AMV sur le climat européen indiquent que l'AMV est susceptible de significativement moduler la température, les précipitations et l'occurrence d'événements extrêmes, en hiver et en été
The anthropogenic warming trend observed during the 20th century in Europe is characterized by fluctuations, which are partly explained by internal climate variability. The physical mechanisms between the Atlantic Multidecadal Variability (AMV, whose internal component contributes to shape atmospheric variability), and the European climate are investigated in this thesis. A comprehensive study of climate models shows a great diversity in the simulation of the teleconnection between the AMV and European summer temperature. The underestimation of its intensity relative to the observations contributes to explain the uncertainties within the decadal climate predictions. Numerical experiments used to assess the mechanisms of influence of the AMV on the European climate indicate that the AMV is likely to significantly modulate temperature, precipitation and the occurrence of extreme events in winter and summer

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Arceño, Mark Anthony. "Changing [Vitivini]Cultures in Ohio, USA, and Alsace, France: An Ethnographic Study of Terroir and the Taste of Place." The Ohio State University, 2021. http://rave.ohiolink.edu/etdc/view?acc_num=osu1610041972377958.

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38

Kulaiappan, Palanisamy Hindumathi. "Le niveau de la mer actuel : variations globales et régionales." Thesis, Toulouse 3, 2016. http://www.theses.fr/2016TOU30166/document.

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Le niveau de la mer est une des variables climatiques essentielles dont la variabilité résulte de nombreuses interactions complexes entre toutes les composantes du système climatique sur une large gamme d'échelles spatiales et temporelles. Au cours du XXème siècle, les mesures marégraphiques ont permis d'estimer la hausse du niveau de la mer global entre 1,6 mm/an et 1,8 mm/an. Depuis 1993, les observations faites par les satellites altimétriques indiquent une hausse du niveau de la mer plus rapide de 3,3 mm/an. Grâce à leur couverture quasi-globale, elles révèlent aussi une forte variabilité du niveau de la mer à l'échelle régionale, parfois plusieurs fois supérieure à la moyenne globale du niveau de la mer. Compte tenu de l'impact très négatif de l'augmentation du niveau de la mer pour la société, sa surveillance, la compréhension de ses causes ainsi que sa prévision sont désormais considérées comme des priorités scientifiques et sociétales majeures. Dans cette thèse, nous validons d'abord les variations du niveau de la mer mesurées par la nouvelle mission d'altimétrie satellitaire, SARAL-AltiKa, en comparant les mesures avec celles de Jason- 2 et des marégraphes. Un autre volet de cette première partie de thèse a consisté à estimer les parts respectives des facteurs responsables des variations du niveau de la mer depuis 2003 en utilisant des observations issues de l'altimétrie satellitaire (missions altimétrique Jason-1, Jason-2 et Envisat), de la mission GRACE, et des profils de température et salinité de l'océan par les flotteurs Argo. Une attention particulière est portée à la contribution de l'océan profond non 'vue' par Argo. Nous montrons que les incertitudes dues aux approches du traitement des données et aux erreurs systématiques des différents systèmes d'observation nous empêchent encore d'obtenir des résultats précis sur cette contribution. Dans la deuxième partie de la thèse, en utilisant les données de reconstruction du niveau de la mer dans le passé, nous étudions la variabilité régionale du niveau de la mer et estimons sa hausse totale (composante régionale plus moyenne globale) de 1950 à 2009 dans trois régions vulnérables: l'océan Indien, la mer de Chine méridionale et la mer des Caraïbes. Pour les sites où l'on dispose de mesures du mouvement de la croûte terrestre par GPS, nous évaluons la hausse locale du niveau de la mer relatif (hausse du niveau de la mer totale plus mouvement de la croûte locale) depuis 1950. En comparant les résultats de ces trois régions avec une étude précédente sur le Pacifique tropical, nous constatons que le Pacifique tropical présente la plus forte amplitude des variations du niveau de la mer sur la période d'étude. Dans la dernière partie de la thèse, nous nous concentrons par conséquent sur le Pacifique tropical. Nous analysons les rôles respectifs de la dynamique océanique, des modes de variabilité interne du climat et du forçage anthropique sur les structures de la variabilité régionale du niveau de la mer du Pacifique tropical depuis 1993. Nous montrons qu'une partie importante de la variabilité régionale du niveau de la mer du Pacifique tropical peut être expliquée par le mouvement vertical de la thermocline en réponse à l'action du vent. En tentant de séparer le signal correspondant au mode de variabilité interne du climat de celui de la hausse régionale du niveau de la mer dans le Pacifique tropical, nous montrons également que le signal résiduel restant (c'est-à-dire le signal total moins le signal de variabilité interne) ne correspond probablement pas à l'empreinte externe du forçage anthropique
Sea level is an integrated climate parameter that involves interactions of all components of the climate system (oceans, ice sheets, glaciers, atmosphere, and land water reservoirs) on a wide range of spatial and temporal scales. Over the 20th century, tide gauge records indicate a rise in global sea level between 1.6mm/yr and 1.8 mm/yr. Since 1993, sea level variations have been measured precisely by satellite altimetry. They indicate a faster sea level rise of 3.3 mm/yr over 1993-2015. Owing to their global coverage, they also reveal a strong regional sea level variability that sometimes is several times greater than the global mean sea level rise. Considering the highly negative impact of sea level rise for society, monitoring sea level change and understanding its causes are henceforth high priorities. In this thesis, we first validate the sea level variations measured by the new satellite altimetry mission, SARAL-AltiKa by comparing the measurements with Jason-2 and tide gauge records. We then attempt to close the global mean sea level budget since 2003 and estimate the deep ocean contribution by making use of observational data from satellite altimetry, Argo profiles and GRACE mission. We show that uncertainties due to data processing approaches and systematic errors of different observing systems still prevent us from obtaining accurate results. In the second part of the thesis, by making use of past sea level reconstruction, we study the patterns of the regional sea level variability and estimate climate related (global mean plus regional component) sea level change over 1950-2009 at three vulnerable regions: Indian Ocean, South China and Caribbean Sea. For the sites where vertical crustal motion monitoring is available, we compute the total relative sea level (i.e. total sea level rise plus the local vertical crustal motion) since 1950. On comparing the results from these three regions with already existing results in tropical Pacific, we find that tropical Pacific displays the highest magnitude of sea level variations. In the last part of the thesis, we therefore focus on the tropical Pacific and analyze the respective roles of ocean dynamic processes, internal climate modes and external anthropogenic forcing on tropical Pacific sea level spatial trend patterns since 1993. Building up on the relationship between thermocline and sea level in the tropical region, we show that most of the observed sea level spatial trend pattern in the tropical Pacific can be explained by the wind driven vertical thermocline movement. By performing detection and attribution study on sea level spatial trend patterns in the tropical Pacific and attempting to eliminate signal corresponding to the main internal climate mode, we further show that the remaining residual sea level trend pattern does not correspond to externally forced anthropogenic sea level signal. In addition, we also suggest that satellite altimetry measurement may not still be accurate enough to detect the anthropogenic signal in the 20 year tropical Pacific sea level trends

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Pauline, Noah Makula. "Living with climate variability and change: lessons from Tanzania." Thesis, 2015. http://hdl.handle.net/10539/20169.

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A Thesis Submitted to the Faculty of Science, University of the Witwatersrand, Johannesburg, in fulfilment of the requirements for the degree of Doctor of Philosophy May, 2015.
There is sufficient evidence supporting that climate change and variability are pervasive realities that are strongly impacting on smallholder farmers in the Great Ruaha River sub-Basin of Tanzania. This PhD study examines smallholder farmers’ vulnerability, coping and adaptation strategies to climate change and variability (including non-climatic stresses), and investigates how such coping and adaptation may be constrained or enhanced given climate variability and change. Both quantitative and qualitative data collection methods were used when engaging with smallholder farmers and government officials. Primary data collection was undertaken in two phases, with phase one using participatory tools (e.g. focus group discussions, wealth ranking, community mapping and transect walk, and historical time lines). Data collected include climatic and non-climatic extreme events, farmers’ perceptions, coping and adaptation strategies. Phase two involved detailed individual interviews (questionnaire surveys) and key informant interviews (case studies), so as to obtain in-depth information on issues of interest. Secondary data were collected from existing statistical sources, literature surveys in archives, libraries and documentation centres, and from governmental agencies (e.g. TMA). Demographic, agricultural production and livestock statistics, and rainfall and temperature records were collected. Results from selected meteorological stations and farmers’ perceptions (74%) indicate that there has been an increase in average maximum temperatures, and both dry and wet years with varying magnitudes during the past four decades. Other climatic stresses include delayed onset and later cessation of the rain seasons. The agreement between farmers’ perceptions and rainfall trends provides good evidence that the climate has become increasingly variable in the GRRB during the past four decades. Achieving sustainable livelihoods is further compounded by non-climatic stresses such as access to markets and coordinating institutions. Results indicate that vulnerability is a complex phenomenon that entails two approaches (end-point and starting-point perspectives). The end-point perspective views vulnerability as the net projected climate change impacts after adaptation has taken place, whilst the starting-point perspective looks at both the current and future multiple stresses and places much emphasis in improving the adaptive capacity. In the study villages, such a nuanced picture highlighted areas for enhanced adaptation strategies. Farmers respond by using various strategies to deal with droughts, floods and other stresses when they occur. During droughts, they mostly use irrigation (canal, pumping and cans), or plant short-term maturing crops. During food shortages, farmers use strategies such as buying food, borrowing money, temporary migration, working in other people’s farms for cash, and reducing consumption. Moreover, the farmers’ choice of adaptation and coping strategies is influenced by factors such as location, access to resources, education levels and institutions. This calls for a whole system approach, which entails defining vulnerability of smallholder farmers to climatic and non-climatic stresses and thus designing appropriate response strategies. For example, mainstreaming adaptation to such stresses when considering development plans, projects, programmes and policies at all scales.

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Abeysirigunawardena, Dilumie Saumedaka. "Climate variability and change impacts on coastal environmental variables in British Columbia, Canada." Thesis, 2010. http://hdl.handle.net/1828/2664.

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The research presented in this dissertation attempted to determine whether climate variability is critical to sea level changes in coastal BC. To that end, a number of statistical models were proposed to clarify the relationships between five climate variability indices representing large-scale atmospheric circulation regimes and sea levels, storm surges, extreme winds and storm track variability in coastal BC. The research findings demonstrate that decadal to inter decadal climatic variability is fundamental to explaining the changing frequency and intensity of extreme atmospheric and oceanic environmental variables in coastal BC. The trends revealed by these analyses suggest that coastal flooding risks are certain to increase in this region during the next few decades, especially if the global sea-levels continue to rise as predicted. The out come of this study emphasis the need to look beyond climatic means when completing climate impact assessments, by clearly showing that climate extremes are currently causing the majority of weather-related damage along coastal BC. The findings highlight the need to derive knowledge on climate variability and change effects relevant at regional to local scales to enable useful adaptation strategies. The major findings of this research resulted in five independent manuscripts: (i) Sea level responses to climatic variability and change in Northern BC. The Manuscript (MC) is published in the Journal of atmospheric and oceans (AO 46 (3), 277-296); (ii) Extreme sea-level recurrences in the south coast of BC with climate considerations. This MC is in review with the Asia Pacific Journal of Climate Change (APJCC); (iii) Extreme sea-surge responses to climate variability in coastal BC. This MC is currently in review in the Annals of the AAG (AN-2009-0098); (iv) Extreme wind regime responses to climate variability and change in the inner-south-coast of BC. This MC is published in the Journal of Atmosphere and Oceans (AO 47 (1), 41-62); (v) Sensitivity of winter storm track characteristics in North-eastern Pacific to climate variability. This manuscript is in review with the Journal of Atmosphere and Oceans (AO (1113)). The findings of this research program made key contributions to the following regional sea level rise impact assessment studies in BC: (i) An examination of the Factors Affecting Relative and Absolute Sea level in coastal BC (Thomson et al., 2008). (ii) Coastal vulnerability to climate change and sea level rise, Northeast Graham Island, Haida Gwaii (formally known as the Queen Charlotte Islands), BC (Walker et al., 2007). (iii) Storm Surge: Atmospheric Hazards, Canadian Atmospheric Hazards Network - Pacific and Yukon Region, C/O Bill Taylor.

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Muhire, Innocent. "Climate change and variability and their impacts on the yields of major food crops in Rwanda." Thesis, 2015. http://hdl.handle.net/10210/13872.

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PhD. (Environmental Management)
Climate change and variability has rapidly emerged as one of the most serious threats to sustainable development especially for developing African countries such as Rwanda. Since most of the agricultural activities in African countries are rain-fed, any adverse change in climate is likely to have a devastating effect on output and the livelihood of the majority of the population in the affected countries. Therefore, there should be continuous and regular preparedness to on-going climate variability. Climate change and variability derived information, are most likely to improve the agricultural outcomes when it is integrated into a framework for decision making to mitigate specific risks. It is in that regard, this research aims at analyzing climate change and variability and their impacts on the yields of major food crops in Rwanda. The raw climatic data (temperatures and precipitations) used in this study were obtained from the Rwandan Meteorological Center based in Kigali and Rwanda Environment Management Authority (REMA) while the agricultural records were collected from the National Institute of Statistics of Rwanda (NISR) and the Ministry of Agriculture and Animal Resources (MINAGRI). Length and completeness of records were the basic criteria used to select weather stations in order to have the most complete dataset. Five major crops, namely beans, cassava, Irish potatoes, maize, and sweet potatoes were selected for investigation because they are grown over large areas in most parts of the country during the two agricultural seasons i.e. season A (September-January) and season B (February-June). This research uses a number of statistical techniques in an attempt to quantify the magnitude and significance in temperature, rainfall, number of rainy days, aridity index and rainfall erosivity changes and variability taking place over Rwanda. The same techniques were applied in determining the magnitude and significance of inter-annual variations in food crop yields over Rwanda. A geographical information system (GIS) was used to present spatially the results on maps...

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Wang, Bin. "Modelling impacts of climate variability and change on wheat cropping across New South Wales." Thesis, 2017. http://hdl.handle.net/10453/90285.

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University of Technology Sydney. Faculty of Science.
Wheat is the most important crop in Australia in terms of the gross value of production. However, in Australia wheat yield is extremely variable from year to year among major production regions, such as New South Wales (NSW), with its agricultural system being significantly affected by water stress and ongoing climate change. To accurately quantify crop yield, and estimate greenhouse gas emissions (GHG) at specific sites and regional scales, it is essential to link spatial information of agro-resources and crop simulation model to assess crop growth in response to agricultural management and environmental variation. The outcomes of this project will enhance the capability of farmers and policy makers to adapt and manage farm outcomes in the face of climate change/variability. For this study, I extracted the historical daily climate data (1900-2010), known as SILO patched point dataset (PPD, http://www.longpaddock.qld.gov.au/silo/ppd/index.php), for maximum and minimum temperature, rainfall, and solar radiation at 894 weather stations evenly distributed across the NSW wheat belt. Wheat yields at shire level during 1922-2000 (data in some shires were not available in some years) across the NSW wheat belt were obtained from Fitzsimmons (2001). Statistical methods were used to quantify the relationship between reported shire wheat yields and climate factors during the wheat-growing season across the NSW wheat belt in eastern Australia from 1922 to 2000. I found that wheat yields were positively correlated to rainfall and minimum temperature while negatively correlated to maximum temperature at a significant level (p<0.05). Growing season rainfall is usually the main direct climatic driver affecting wheat yields variation in this semi-arid area, but the indirect effects of temperature and solar radiation are also important. A detailed understanding of how historical climate variation has impacted on wheat yield can provide useful insights for the development of sustainable agricultural systems in the face of future climate change. I used the statistical downscaling and bias-correction method developed by Liu and Zuo (2012) to generate realistic daily site-specific climate data from monthly GCM output on a coarse-resolution grid. Briefly, monthly GCM output data (solar radiation, rainfall, daily maximum and minimum temperature) from each of the selected GCMs were downscaled to the 894 observation sites using an inverse distance-weighted interpolation method. Biases were then corrected using a transfer function derived from interpolated GCM data and observed data for the sites. Daily climate data for each of 894 sites under two RCPs for 1900-2100 were generated by a modified stochastic weather generator (WGEN) with parameters derived from the bias-corrected monthly data. The results show that wheat growing season rainfall is projected to decrease under different future scenarios across the NSW wheat belt. Future climate projected an averaged warming of 2.1˚C for RCP4.5 and 3.8˚C for RCP8.5 across this region in 2061-2100 compared to the baseline period 1961-2000. A crop simulation model (APSIM) driven by statistical downscaling data was used to simulate wheat productivity and water use efficiency under the CMIP5 multimodel ensemble projections across the NSW wheat belt. Despite an acceleration of crop development and shortening of growth duration together with declining growing season rainfall, GCMs projected that multi-model median yields could increase by 0.4% (4704 kg/ha) for RCP4.5 and 7.3% (5027 kg/ha) for RCP8.5 by 2061-2100. These results show that drier area would benefit more from elevated CO₂ than wetter area in the NSW wheat belt. Without the increase in CO₂ concentration simulated wheat yield decrease rapidly under RCP4.5 by 2061-2100 and much more so under RCP8.5 compared to the present. The simulated evapotranspiration (ET) decreased by 11.9% (282 mm) for RCP4.5 and 18.8% (260 mm) for RCP8.5 over the whole wheat belt. Increasing yields combined with decreasing ET resulted in simulated water use efficiency increasing by 11.4% (15.4 kg ha⁻¹ mm⁻¹) for RCP4.5 and 29.3% (17.8 kg ha⁻¹ mm⁻¹) for RCP8.5. Wheat production in water-limited, low yielding environments appears to be less negative impacted or in some cases even positively affected under future climate change and elevated CO₂, compared to other growing environments in the world. Agro-ecosystems have high spatial heterogeneity and temporal variation of productivity, arising from the spatial and temporal variability of climate, soil texture/water, and management practices. Furthermore, the projected yield increase in the future could be overestimated because the crop model generally does not sufficiently account for yield reduction due to diseases, pests and weeds. I did not explicitly consider certain aspects such as efficient management practices, breeding new crop cultivars, which will obviously have a significant impact on wheat yield in the future. Therefore, these current simulated results would provide a baseline for future adaptive strategies such as incorporating new traits into new cultivars in new management systems not currently available.

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Yip, Queenie. "Climate impacts on hydrometric variables in the Mackenzie River Basin." Thesis, 2008. http://hdl.handle.net/10012/3542.

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The research described in this thesis examines how the hydrologic cycle is affected by climate changes in the Mackenzie River Basin (MRB) in northern Canada. The study focuses on five hydro-meteorological variables; runoff, evapotranspiration, storage, temperature and precipitation. Two different climate input data sets were used: Environment Canada gridded observed data and the European Center for Medium range Weather Forecasting (ECMWF) Re-Analysis climate data (ERA-40). In both data sets, runoff and evapotranspiration were modelled using the WATFLOOD hydrological model for the period of 1961 to 2002 on a 20 by 20 km grid. Trends were assessed on a monthly and annual basis using the Mann-Kendall non-parametric trend test. The hydrologic cycle in the MRB appears to be strongly influenced by climate change. The results reveal a general pattern of warming temperatures, and increasing precipitation and evapotranspiration. Overall decreases in runoff and in storage were detected from the Environment Canada data set while increases in runoff and in storage were detected from the ECMWF data set. The trends in runoff and evapotranspiration reflected changes in both precipitation and temperature. The spatial pattern of changes in runoff followed the pattern of change in precipitation very closely in most of the months, with the exception of March and October. The effect of changes in temperature is much more noticeable than that of changes in precipitation in March and October. The change in spatial distribution of evapotranspiration, on the other hand, matched the pattern of changes in temperature better; yet its seasonal pattern follows more closely to that of precipitation. The sensitivity of annual runoff to changes in climate was also estimated using a nonparametric estimator. Among the most important findings are: 1) runoff was more sensitive to precipitation and less sensitive to temperature; 2) runoff was positively correlated with precipitation and evapotranspiration; 3) runoff was negatively correlated with temperature, implying any increase in melt runoff from glaciers caused by increases in temperature were offset by losses due to evapotranspiration within the basin; 4) soil moisture storage may play an important role in the runoff and evapotranspiration processes; and 5) the sensitivity of mean annual runoff to changes in precipitation and evapotranspiration is typically lower along the Rocky Mountain chain, higher in the central zone of the Interior Plain, and highly varied in the Canadian Shield region in the basin. Correlation analysis suggested that the agreement between the two data sets is very weak at the grid-cell level. However, there was broad degree of consistencies in the seasonal and spatial patterns of trends between the two data sets, suggesting that the data are more reliable for identifying hydrological changes on a regional scale than at grid-cell level.

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Raje, Deepashree. "Hydrologic Impacts Of Clmate Change : Quantification Of Uncertainties." Thesis, 2009. http://hdl.handle.net/2005/1064.

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General Circulation Models (GCMs), which are mathematical models based on principles of fluid dynamics, thermodynamics and radiative transfer, are the most reliable tools available for projecting climate change. However, the spatial scale on which typical GCMs operate is very coarse as compared to that of a hydrologic process and hence, the output from a GCM cannot be directly used in hydrologic models. Statistical Downscaling (SD) derives a statistical or empirical relationship between the variables simulated by the GCM (predictors) and a point-scale meteorological series (predictand). In this work, a new downscaling model called CRF-downscaling model, is developed where the conditional distribution of the hydrologic predictand sequence, given atmospheric predictor variables, is represented as a conditional random field (CRF) to downscale the predictand in a probabilistic framework. Features defined in the downscaling model capture information about various factors influencing precipitation such as circulation patterns, temperature and pressure gradients and specific humidity levels. Uncertainty in prediction is addressed by projecting future cumulative distribution functions (CDFs) for a number of most likely precipitation sequences. Direct classification of dry/wet days as well as precipitation amount is achieved within a single modeling framework, and changes in the non-parametric distribution of precipitation and dry and wet spell lengths are projected. Application of the method is demonstrated with the case study of downscaling to daily precipitation in the Mahanadi basin in Orissa, with the A1B scenario of the MIROC3.2 GCM from the Center for Climate System Research (CCSR), Japan. An uncertainty modeling framework is presented in this work, which combines GCM, scenario and downscaling uncertainty using the Dempster-Shafer (D-S) evidence theory for representing and combining uncertainty. The methodology for combining uncertainties is applied to projections of hydrologic drought in terms of monsoon standardized streamflow index (SSFI-4) from streamflow projections for the Mahanadi river at Hirakud. The results from the work indicate an increasing probability of extreme, severe and moderate drought and decreasing probability of normal to wet conditions, as a result of a decrease in monsoon streamflow in the Mahanadi river due to climate change. In most studies to date, the nature of the downscaling relationship is assumed stationary, or remaining unchanged in a future climate. In this work, an uncertainty modeling framework is presented in which, in addition to GCM and scenario uncertainty, uncertainty in the downscaling relationship itself is explored by linking downscaling with changes in frequencies of modes of natural variability. Downscaling relationships are derived for each natural variability cluster and used for projections of hydrologic drought. Each projection is weighted with the future projected frequency of occurrence of that cluster, called ‘cluster-linking’, and scaled by the GCM performance with respect to the associated cluster for the present period, called ‘frequency scaling’. The uncertainty modeling framework is applied to a case study of projections of hydrologic drought or SSFI-4 classifications, using projected streamflows for the Mahanadi river at Hirakud. It is shown that a stationary downscaling relationship will either over- or under-predict downscaled hydrologic variable values and associated uncertainty. Results from the work show improved agreement between GCM predictions at the regional scale, which are validated for the 20th century, implying that frequency scaling and cluster-linking may indeed be a valid method for constraining uncertainty. To assess the impact of climate change on reservoir performance, in this study, a range of integrated hydrologic scenarios are projected for the future. The hydrologic scenarios incorporate increased irrigation demands; rule curves dictated by increased need for flood storage and downscaled projections of streamflow from an ensemble of GCMs and emission scenarios. The impact of climate change on multipurpose reservoir performance is quantified, using annual hydropower and RRV criteria, under GCM and scenario uncertainty. The ‘business-as-usual’ case using Standard Operating Policy (SOP) is studied initially for quantifying impacts. Adaptive Stochastic Dynamic Programming (SDP) policies are subsequently derived for the range of future hydrologic scenarios, with the objective of maximizing reliabilities with respect to multiple reservoir purposes of hydropower, irrigation and flood control. It is shown that the hydrologic impact of climate change is likely to result in decreases in performance criteria and annual hydropower generation for Hirakud reservoir. Adaptive policies show that a marginal reduction in irrigation and flood control reliability can achieve increased hydropower reliability in future. Hence, reservoir rules for flood control may have to be revised in the future.

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"The Impacts of Geography and Climate Change on Magdalenian Social Networks." Doctoral diss., 2017. http://hdl.handle.net/2286/R.I.44052.

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abstract: This dissertation uses a comparative approach to investigate long-term human- environment interrelationships in times of climate change. It uses Geographical Information Systems and ecological models to reconstruct the Magdalenian (~20,000- 14,000 calibrated years ago) environments of the coastal mountainous zone of Cantabria (Northwest Spain) and the interior valleys of the Dordogne (Southwest France) to contextualize the social networks that could have formed during a time of high climate and resource variability. It simulates the formation of such networks in an agent-based model, which documents the processes underlying the formation of archaeological assemblages, and evaluates the potential impacts of climate-topography interactions on cultural transmission. This research then reconstructs the Magdalenian social networks visible through a multivariate statistical analysis of stylistic similarities among portable art objects. As these networks cannot be analyzed directly to infer social behavior, their characteristics are compared to the results of the agent-based model, which provide characteristics estimates of the Magdalenian latent social networks that most likely produced the empirical archaeological assemblage studied. This research contributes several new results, most of which point to the advantages of using an inter-disciplinary approach to the study of the archaeological record. It demonstrates the benefits of using an agent-based model to parse social data from long- term palimpsests. It shows that geographical and environmental contexts affect the structure of social networks, which in turn affects the transmission of ideas and goods that flow through it. This shows the presence of human-environment interactions that not only affected our ancestors’ reaction to resource insecurities, but also led them to innovate and improve the productivity of their own environment. However, it also suggests that such alterations may have reduced the populations’ resilience to strong climatic changes, and that the region with diverse resources provided a more stable and resilient environment than the region transformed to satisfy the immediate needs of its population.
Dissertation/Thesis
Appendix_D_Sites_Dates
Appendix_E_Flowchart_Biome_Reconstruction
Appendix_H_Flowchart_ABM
Appendix_I_Flowchart_Social_Network
Appendix_J_Portable_Art_Objects
Appendix_J_Art_Characteristics
Appendix_L_Poster_Summary
Appendix_A_Prehistoric_Fauna
Appendix_B_Modern_PFT_Distribution
Appendix_C_Prehistoric_PFT_Distribution
Doctoral Dissertation Anthropology 2017

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Kelley, Colin Patrick. "Recent and future drying of the Mediterranean region: anthropogenic forcing, natural variability and social impacts." Thesis, 2014. https://doi.org/10.7916/D8CR5RFV.

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The Mediterranean region has experienced persistent drying since the middle of the 20th Century and global climate models project further drying in the future as a consequence of increasing greenhouse gases. The Mediterranean region is also known to oscillate between decades of relatively wet and dry conditions due to the strong influence of multidecadal North Atlantic Oscillation (NAO). It is therefore of great importance to understand the relationship between forced long-term drying resulting from human influences and those due to natural variability. To this end, we used observations, reanalyses and comprehensive global climate models in this thesis research. The roles of anthropogenic climate change and internal climate variability in causing the Mediterranean region's late 20th Century extended winter drying trend were examined using 20th Century observations as well as 19 coupled climate models from the CMIP3. The drying was strongly influenced by the robust positive trend in the NAO from the 1960s to the 1990s. Model simulations and observations were used to assess the probable relative roles of radiative forcing and internal variability in explaining the circulation trend that drove much of the precipitation change. It was concluded that the radiatively forced trends were a small fraction of the total observed trends. Instead it was argued that the robust trends in the observed NAO and Mediterranean rainfall during this period were largely due to multidecadal internal variability with a small contribution from the external forcing. Differences between the observed and NAO associated precipitation trends are consistent with those expected as a response to radiative forcing. The radiatively forced trends in circulation and precipitation are expected to strengthen in the current century and these results highlight the importance of their contribution to future precipitation changes in the region. The Mediterranean precipitation climatology and trend were further examined by comparing the newest generation of global climate models (CMIP5) used in the Intergovernmental Panel on Climate Change (IPCC) Fifth Assessment Report, to the previous generation (CMIP3) and to observations over the latter half of the 20th Century for both the summer and winter half years. The observed drying trend since 1950 was predominantly due to winter drying, with very little contribution from the summer. However, in the CMIP5 multimodel mean, the precipitation trend since 1950 is evenly divided throughout the seasonal cycle. This may indicate that in observation, multidecadal internal variability, particularly that associated with the NAO, dominates the wintertime trend. An estimate of the observed externally forced trend showed that winter drying dominated in observations but the spatial patterns were grossly similar to the multimodel mean trend. The similarity was particularly robust in the eastern Mediterranean region, indicating a radiatively forced component being stronger there. These results also revealed modest improvement for the CMIP5 multimodel ensemble in representation of the observed six-month winter and summer climatology. We further explored the detailed mechanisms leading to the NAO-associated precipitation change, such as the role of the change in mean circulation versus that of the storm tracks in the regional moisture budget, which had not been investigated previously. We employed a moisture budget analysis using 15 CMIP5 models and the ERA-Interim Reanalysis to investigate the relationship between the NAO and the various moisture budget terms for the six-month winter and summer. Compared with the ERA-Interim, the models performed well in their simulation of the relationship between the naturally varying NAO and the large-scale moisture budget. Our results indicated that the shift in the midlatitude transient eddies induced modest moisture convergence, rather than divergence, over the Mediterranean under a positive NAO. The reduction in precipitation in this region during a positive NAO was dominated by the mean moisture divergence, which opposed the transient contribution. There were significant differences between the patterns of NAO-induced moisture budget anomaly and changes due to external radiative forcing. Under radiative forcing there was enhanced evaporation over the Mediterranean Sea, Italy and eastern Europe and drying by the shift in the wintertime storms over nearly all of Europe and the Mediterranean. Under a positive phase of the NAO, on the other hand, there was modest reduction in evaporation and wetting by the storms over the Mediterranean, and drying over northern Europe. The dependence of the Mediterranean moisture budget on the NAO was similarly explored in the summer half of the year and in this season the models exhibited more disagreement with observations, but otherwise showed the similar results as winter. The stronger anthropogenic induced drying signal over the eastern Mediterranean provided a basis to examine the possible cause and impact of the recent severe and persistent drought in Syria that occurred directly prior to the uprising of 2011. The drought devastated Syrian agriculture, resulting in food shortages, widespread unemployment, the collapse of rural social structure and a mass migration of agricultural refugees to Syria's urban areas. Anger at the government's failure to ameliorate conditions was one spark for the uprising that evolved into civil war. We found that though droughts occur periodically in Syria due to natural causes it is likely that the recent drought was more extreme due to the century long drying trend caused by increased radiative forcing. It was estimated that the anthropogenic trend made a drought of such severity several times more likely. Droughts as persistent as the recent one are projected to be commonplace in a future warmer world.

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Daghagh, Yazd Sahar. "Impacts of climatic variability, water scarcity and socio-economic demographics on farmers’ mental health in Australia." Thesis, 2019. http://hdl.handle.net/2440/122612.

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Climatic conditions in recent decades have been characterised with more frequent, long-term, and severely adverse events (e.g. drought) occurring in many countries. Many studies have found a link between various climatic evens and their negative impact on societies’ health, wellbeing and work productivity. In particular, there has been an increasing focus in the literature on the link between mental health and climatic variability, especially for rural communities. This is especially so for farming communities in Australia’s Murray-Darling Basin (MDB). MDB farmers have experienced significant increases in temperature and evaporation over the past three decades, and reductions in rainfall and runoff due to climate change. The main question investigated in this thesis was to try to understand the key stress factors affecting farmers’ mental health around the world, particularly focussing upon the consequences of climatic variability for farmers (both dryland and irrigators) in the MDB. To answer this question, a mixed-methods approach was employed involving: a) a systematic review of 167 articles on farmers’ mental health, using a standardised electronic literature search strategy and PRISMA guidelines, to understand the potential key stressors affecting farmers’ mental health around the world; b) Correlative Random Effects panel data regression analysis of MDB farmers’ (2,141 observations), and all Australian farmers (5,426 observations) mental health using 14 waves (2001-02 to 2014-15) of the national longitudinal survey from the ‘Household, Income and Labour Dynamics in Australia’ and utilising spatial analysis from various climate, agricultural and water databases (e.g. rainfall, drought periods, soil moisture, maximum summer temperatures); and c) Ordered Probit regression modelling of the influences on irrigator mental health, using a 2015-16 survey sample of 1,000 irrigators in the southern MDB, merged with a variety of spatial data (e.g. drought, water allocation and temperature). Key findings of this thesis show that water scarcity was associated with MDB farmers (both dryland and irrigators) worsening mental health. In particular, the most important proxies of water scarcity were found to be rainfall, low water allocations, and higher summer temperatures. Results also highlight the importance of financial capital in influencing southern MDB irrigators’ psychological distress, with net farm income, debt, productivity changes, and land capital value being the most important influences, respectively. This thesis also provides some evidence that landholder governance and natural resource management (such as being a certified organic irrigator) statistically positively influenced southern MDB irrigators’ mental health, especially in the horticultural industry (where larger sample sizes were available). These findings will become increasingly policy-relevant, given the increasing pressure placed on farming communities by the impacts of climate change, along with the fact that financial problems are increasing in drought-affected areas across Australia. Key recommendations of this thesis indicate the need for a strong focus on policy that is designed to build greater natural farming and financial capital on-farms, and encourage higher risk-management strategies to withstand a drier future in Australia. In summary, the focus must be to integrate: 1) drought/climate change policy; 2) mental health policy; 3) natural resource management/extension policy; and 4) rural economic and social development policy.
Thesis (Ph.D.) -- University of Adelaide, Centre for Global Food and Resources, 2019

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Ginn, Joel. "Getting the Message Across: Flexitarians as Messengers for Meat's Climate Change Impacts." 2021. https://scholarworks.umass.edu/masters_theses_2/1012.

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Meat consumption has been a prominent part of humanity’s dietary culture, particularly in modern, Western developed nations. However, recent research has shown that collectively reducing our consumption of animal products can have major benefits for mitigating our environmental footprint. Despite a consensus among climate scientists on its potential impact, the public does not recognize the effectiveness of this behavioral shift. Recent efforts to address this have created movements and organizations that focus on reduction of meat consumption (e.g. flexitarianism, reducetarianism, Meatless Mondays), rather than elimination of meat consumption (e.g. vegetarianism, veganism) with the intent of creating a more acceptable message, from a less stigmatized group, thereby reaching more people and resulting in greater change. However, the relative impact of these messages has not been compared in previous work. The present research investigates the perceptions of these messages and messengers to assess if there are differences in how people respond to these messages and change their intentions. Study 1 examined interpersonal communication, testing the difference between a message of giving up meat, coming from a vegetarian, and a message of reducing meat consumption, from a reducetarian. Study 2 extended Study 1, replicating the study while adding a third condition to further differentiate the effects of message and messenger using a reduction focused article from a vegetarian. Study 3 extended the previous studies to communication from NGOs with explicit goals as reducetarian or vegetarian. Across all studies, we find that people are more willing to share messages from a reducetarian perspective than a vegetarian one, people agree with that message more, and indicate that they are closer to reducing up meat consumption after reading that article.

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Matimolane, Selelo Wilson. "Impacts of Climate Variability and Change on Maize (Zea may) production in Makhuduthamaga Local Municipality, Limpopo Province, South Africa." Diss., 2018. http://hdl.handle.net/11602/1179.

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MENVSC (Geography)
Department of Geography and Geo-Information Sciences
Climate variability and change directly affect agricultural production. This is because the agricultural sector is inherently sensitive to climatic conditions and is one of the most vulnerable sectors to risks and impact of global climate change. The aim of this study was to determine maize producer's vulnerability and assess the impact of climate variability and change on maize production in the Makhuduthamaga Local Municipality, of Limpopo Province, South Africa. Climatic and maize yields data utilized in the study are for the period 1985 - 2015). Interviews were also conducted with the producers and various officials from government and non-governmental sectors. The results illustrate significant rainfall and temperature variations both spatially and temporally. The variations observed in the average rainfall and rain days for the period under consideration were not related to the variation in yield of maize for the same period. The regression results revealed low R² values, indicating a weak relationship between maize yields, rain days and rainfall. Furthermore, the results revealed a significant positive relationship between annual rainfall and temperature (r²<0.05 and P<0.05) but not a significant relationship with maize yields. The results of the qualitative data showed that the producers’ perception of the occurrence of climate variability was high, as 65.7% of the respondents indicated that the state of climate is increasingly variable. About 61.5% of the producers implemented or adopted an adaptation strategy to cope with the perceived climate variability and change. Age, gender and access to extension services were determined as important factors that determine the adoption of adaptation strategies. The vulnerability assessment revealed that producers were highly vulnerable to changing climate; this exposes producers to the risks of crop failure, loss of income and food insecurity. The study recommended (a) intervention and adaptation strategies that target mitigation of decreased rainfall impacts (b) increased access to extension service (c) empirical research around the impacts of climate change to increase producers’ level of awareness.
NRF

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Maponya, Phokele Isaac. "Climate change and agricultural production in Limpopo Province : impacts and adaptation options." Thesis, 2012. http://hdl.handle.net/10500/19116.

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The primary aim of my research was to identify the impacts and adaptation options of climate variability and change on agricultural production in Limpopo province. The following objectives were identified: To understand the impacts of climate variability and change on agricultural production in Limpopo province , To assess the impacts of climate variability and change on agricultural production in Limpopo province and To identify adaptation measures that reduces the impacts of climate variability and change on agricultural production in Limpopo province. A representative sample of 300 farmers aged 16- 65+ years (46 percent males and 54 percent females) participated in the study. The study involved Sekhukhune and Capricorn districts, with 56 percent farmers in Capricorn and 44 percent in Sekhukhune district. The following 11 local municipalities were visited: Elias Motsoaledi, Makhuduthamaga, Fetakgomo, Ephraim Mogale, Tubatse, Lepelle Nkumpi, Blouberg, Aganang, Polokwane, and Molemole. The Limpopo province is one of the poorest provinces in the country, characterized by high unemployment rate, poverty and lack of access to a range of resources that frustrate majority of people ability to secure their livelihoods. In this study the province's economic, biological and physical environment were highlighted. The study further covers the province, s farming enterprises, systems, categories, infrastructure as well as other constraints that maybe facing the emerging farmer in the province. It is assumed that the majority of farmers in both the Capricorn and Sekhukhune districts are using different coping and adaptation strategies in order to increase their crop yields. Literature studies show that climate variability and change adaptation strategies vary from area to area due to agro ecological zones and the harshness of the effects of climate variability and change. It has also been noted that climate change is fast pushing the poorest and most marginalized communities beyond their capacity to respond. This study draws on lessons learned, experiences, and other existing research on climate change impacts and adaptation across the globe. It sets out what is needed to enable people living in poverty to adapt to climate change, and a range of interventions that are available across climate - sensitive sectors. The study has provided a literature review of the impact of climate change on the agricultural sector. In fact, it has documented some of the likely impacts of climate change based on International, continental, regional, national and provincial agricultural sector. The study highlighted the impact of climate change also on various climate - sensitive sectors including understanding water resources, forestry, natural ecosystem human health, infrastructure and coastal zones. This research also confirmed that being a full time farmer, gender, information on climate change, information received through extension services and adaptation to climate change are some of the important determinants of agricultural production, food scarcity and unemployment. A worrying situation is reviewed globally in this study and it can be concluded that climate variability and change is affecting every sector in society and it needs urgent attention. Statistics was used to determine climate variability and change impact on agricultural production. Results indicate that farmers are aware that Limpopo province is getting warmer and drier with increased frequency of droughts, changes in the timing of rains, observed trends oftemperature and precipitation. The study also presented perceived adaptation strategies used by farmers in Limpopo province. Some of their perceived adaptation strategies included: (a) Soil management strategies, (b) Water management strategies and (c) Others like use of subsidies and use of insurance. Other important adaptation options being used by farmers were also discussed in this study including different adaptation measures against colds, heat, frost, abnormal wind, hail, lack of extension support, nematodes, insecticides, worms, temperature and rainfall. The results of this study are potentially valuable to the agricultural sector considering the threats that climate change poses across climate sensitive sectors.
Environmental Sciences
D. Phil. (Environmental Management)

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