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Vice, President Research Office of the. "Sea Change." Office of the Vice President Research, The University of British Columbia, 2009. http://hdl.handle.net/2429/9510.
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Jakub, Lucy(Lucy Marita). "Sea of change." Thesis, Massachusetts Institute of Technology, 2020. https://hdl.handle.net/1721.1/130207.
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Thesis: S.M., Massachusetts Institute of Technology, Department of Humanities, September, September, 2020Cataloged from student-submitted PDF version of thesis.
Includes bibliographical references (pages 13-16).
The Gulf of Maine is warming at a faster rate than 99.9 percent of the world ocean, a trend with uncertain implications for the last great maritime fishery: American lobster. Every year, fishermen, scientists, and managers wait to see if the fishery reverses its fantastic growth, which has been a salutary effect of climate change over the past three decades. The gulf has as many horizons as it has islands, and nobody knows the whole thing. Like the story of the blind men and the elephant, every person you ask, even the most expert, will describe a different gulf to you, and a different crisis. What's clear is that the ecosystems of the region have been shaped by many different pressures: domesticated by management, depleted by overfishing, shuffled by natural climatic cycles. The future of the gulf will depend not just on the trajectory of ocean warming, but on whether people can rethink the way we use the environment, and adapt to a changing world.
by Lucy Jakub.
S.M.
S.M. Massachusetts Institute of Technology, Department of Humanities
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Sandin, Jetta Christine. "Sea Change or Charade." Thesis, Boston College, 2004. http://hdl.handle.net/2345/475.
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Thesis advisor: Timothy W. CrawfordFollowing the devastation UN peacekeeping experienced in the 1990s, the United Nations Panel on Peace Operations wrote a report, known as the Brahimi Report, that contained twenty key recommendations as how to make peacekeeping more effective and efficient. These recommendations addressed certain fundamental flaws in peacekeeping practices and procedures. This paper discusses the purpose behind several key recommendations and examines the political and internal debate surrounding their implementation. It addresses the effect of the Brahimi Report on UN reform and concludes that the Brahimi Report has spurred a long needed examination of peacekeeping and has influenced progress in most areas, even though most of the actual suggestions of the Panel were not followed
Thesis (BA) — Boston College, 2004
Submitted to: Boston College. College of Arts and Sciences
Discipline: Political Science
Discipline: College Honors Program
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Hentati-Sundberg, Jonas. "SEA CHANGE : Social-ecological co-evolution in Baltic Sea fisheries." Doctoral thesis, Stockholms universitet, Stockholm Resilience Centre, 2015. http://urn.kb.se/resolve?urn=urn:nbn:se:su:diva-122372.
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Sustainable management of natural resources requires an in-depth understanding of the interplay between social and ecological change. Linked social-ecological systems (SES) have been described as complex adaptive systems (CAS), which mean that they are irreducible, exhibit nonlinear dynamics, have interactions across scales and are uncertain and unpredictable. These propositions have however rarely been tested empirically, in part due to a lack of methodological approaches and suitable datasets. In this thesis, I address this methodological and empirical gap in a study of long-term change of Baltic Sea fisheries. In Paper I, we develop the concept of fishing style through integrating multivariate statistical analysis and in-depth interviews. We thereby identify an intermediate level of detail for analyzing social-ecological dynamics, embracing the case specific and context dependent approaches of the social sciences with the generalizable and quantifiable approaches from the natural sciences. In Paper II we ask: How has the Baltic Sea fishery been regulated over time, and can we identify a way to quantify regulations in order to be able to analyze their effects? We analyze all regulatory changes in Sweden since 1995 with a new methodology and conclude that there is a clear trend towards increased micro-management. In Paper III, we use the fishing styles developed in Paper I and examine how they have changed over time. We relate these changes to the dynamics of regulation (Paper II), as well as to the dynamics of fish stocks and prices. We conclude that regulation has been the main driving force for observed changes, but also that regulation has prompted significant specialization and decline in flexibility for fishers over time. These changes are unintended consequences and may represent a looming risk for the long-term sustainability of this social-ecological system. Paper IV zooms in on a particular fishery, the pelagic trawl fishery for sprat Sprattus sprattus and Atlantic herring Clupea harengus, mainly targeted for the production of fishmeal and fish oil. Suspicions of non-compliance in this fishery motivated us to apply a statistical approach where we used socioeconomic data to re-estimate the historical catches in this fishery (a novel approach to catch-reconstruction estimates). We found that catches had been significantly underreported over several years, with consequences for the quality of stock assessments and management. The study underlines the importance of understanding linked social, economic and ecological dynamics for sustainable outcomes. Finally, Paper V takes a longer historical look at the Baltic Sea fishery, using regionally disaggregated data from 1914-2009 (96 years), which were analyzed with a novel type of nonlinear statistical time-series methods (Empirical Dynamical Modeling). Our analysis explicitly recognized the potential nonlinear dynamics of SES and showed high predictability across regions of catches and prices of cod Gadus morhua and herring. The signal was generally nonlinear and predictability decreased strongly with time, suggesting that the dynamics of this SES are ever-changing. To our knowledge, this is the first long-term analysis of a SES using empirical data and methods developed from the CAS field of research. The main contributions of this thesis are the integrated analysis of social and ecological data, the development of novel methods for understanding SES dynamics, insights on the ever-changing nature of CAS and the quantitative analysis of management outcomes. Future work should focus on assessing the generality of these findings across a broad range of SES and evaluate alternative governance approaches given the complexity and uncertainty of SES suggested by this thesis.At the time of the doctoral defense, the following paper was unpublished and had a status as follows: Paper 5: Manuscript.
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Daly, Julia. "Late holocene sea-level change around Newfoundland." Fogler Library, University of Maine, 2002. http://www.library.umaine.edu/theses/pdf/DalyJ2002.pdf.
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Desflots, Melicie. "Environmental and Internal Controls of Tropical Cyclones Intensity Change." Scholarly Repository, 2008. http://scholarlyrepository.miami.edu/oa_dissertations/120.
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Tropical cyclone (TC) intensity change is governed by internal dynamics (e.g. eyewall contraction, eyewall replacement cycles, interactions of the inner-core with the rainbands) and environmental conditions (e.g. vertical wind shear, moisture distribution, and surface properties). This study aims to gain a better understanding of the physical mechanisms responsible for TC intensity changes with a particular focus to those related to the vertical wind shear and surface properties by using high resolution, full physics numerical simulations. First, the effects of the vertical wind shear on a rapidly intensifying storm and its subsequent weakening are examined. Second, a fully coupled atmosphere-wave-ocean model with a sea spray parameterization is used to study the impact of sea spray on the hurricane boundary layer. The coupled model consists of three components: the high resolution, non-hydrostatic, fifth generation Pennsylvania State University-NCAR mesoscale model (MM5), the NOAA/NCEPWAVEWATCH III (WW3) ocean surface wave model, and theWHOI threedimensional upper ocean circulation model (3DPWP). Sea spray parameterizations were developed at NOAA/ESRL and modified by the author to be introduced in uncoupled and coupled simulations. The model simulations are conducted in both uncoupled and coupled modes to isolate various physical processes influencing TC intensity. The very high-resolutionMM5 simulation of Hurricane Lili (at 0.5 km grid resolution) showed a rapid intensification associated with a contracting eyewall. Changes in both the magnitude and the direction of the vertical wind shear associated with an approaching upper-tropospheric trough were responsible for the weakening of the storm before landfall. Hurricane Lili weakened in a 5-10 m/s vertical wind shear environment. The simulated storm experienced wind shear direction normal to the storm motion, which produced a strong wavenumber one rainfall asymmetry in the downshear-left quadrant of the storm. The rainfall asymmetry was confirmed by various observations from the TRMM satellite and the WSR-88D ground radar in the coastal region. The increasing vertical wind shear induced a vertical tilt of the vortex with a time lag of about 5-6 hours after the wavenumber one rainfall asymmetry was first observed in the model simulation. Other key factors controlling intensity and intensity change in tropical cyclones are the air-sea fluxes. Accurate measurement and parameterization of air-sea fluxes under hurricane conditions are challenging. Although recent studies have shown that the momentum exchange coefficient levels off at high wind speed, little is known about the high wind behavior of the exchange coefficient for enthalpy flux. One of the largest uncertainties is the potential impact of sea spray. The current sea spray parameterizations are closely tied to wind speed and tend to overestimate the mediated heat fluxes by sea spray in the hurricane boundary layer. The sea spray generation depends not only on the wind speed but also on the variable wave state. A new spray parameterization based on the surface wave energy dissipation is introduced in the coupled model. In the coupled simulations, the wave energy dissipation is used to quantify the amount of wave breaking related to the generation of sea spray. The spray parameterization coupled to the waves may be an improvement compared to sea spray parameterizations that depends on wind speed only.
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Hamlin, Samantha L. Miner Benjamin G. "Predation and thermal stress affect color change in the symbiotic sea anemone Aiptasia /." Online version, 2009. http://content.wwu.edu/cdm4/item_viewer.php?CISOROOT=/theses&CISOPTR=359&CISOBOX=1&REC=17.
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Fenoglio-Marc, Luciana. "Satellite geodesy for sea level and climate change." TU Darmstadt, 2015. https://tuprints.ulb.tu-darmstadt.de/4412/1/Fenoglio_Habil2015_v3.pdf.
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This habilitation thesis presents the findings of the sea level change studies conducted at the Institute of Geodesy of the Technischen Universität Darmstadt betweeen 2001 and 2013.
Sea level is an important indicator of climate change. It has been traditionally measured by coastal tide gauges and by satellite altimetry since 1993. Tide gauge measurements indicate a coastal average sea level rise of 1-2 millimeters per year over the 20th century. Over the last two decades the average sea level rise increased to 3.3±0.7 millimeters per year, consistently measured by tide gauges and satellite altimetry. The 2013 Intergovernmental Panel on ClimateChange (IPCC AR5) predicts a global mean rise of 50 ± 20 cm by 2100 for a medium warming scenario for the interval 2081-2100.
Sea level rise is not uniform and some regions will be more affected than others. It can possibly exacerbate the effects of other factors, such as flooding and ground subsidence. Because of its potential impact on coastal regions, rising sea level is one of the major threatsof climate warming. Changes in each component of the climate system, ocean, land and ice sheets, affects sea level. The two primary contributors of sea level rise, thermal expansion due to ocean warming and melting of continental glaciers and ice sheets, have been identifiedbut large uncertainties remain. Locally non-climatic components, as subsidence, can causerelative sea level rise much larger than the global average mean sea level rise.
The global and highly accurate analysis of sea level variations is made possible by spacebasedtechniques. Their main innovation is the use of the same accurate and global reference frame ensuring long-term, precise monitoring and integration in a Global Geodetic ObservingSystem, which is crucial for many practical applications.
This thesis focuses on the use of geodetic techniques. Its aim is a comprehensive analysis of the regional sea level variability and of its causes with particular attention to the coastalzone.
The three main scientific objectives are: improvement of multi-mission satellite altimetry records, quantification of global and regional sea level change and attribution of sea level rise.
Firstly the altimeter data from different missions are unified, improved in the coastal zoneand validated with in-situ and model data. Secondly global and regional estimations of sea level variability from altimetry and tide gauge data are made. The third part of the work is dedicated to the analysis of the reason for sea level change.
Here satellite altimetry andgravity missions data are combined with model data to detect the causes of this variation. The analysis includes the separation of mass and volume sea level change and the closing of the water budget.
This work shows the challenges of merging satellite data of different types for the understanding of physical processes in sea basins. It also deals with the challenges of new satellite altimetry missions in the coastal zone, where altimetry provides a consistent link to tide
gauge stations co-located with Global Navigation Satellite System observations. It finally discusses the importance of highly accurate sea level variability and trends for modeling coastal
processes and for long-term predictions.
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Miller, Jason R. "An analysis of the Sea Enterptise program." Thesis, Monterey, Calif. : Springfield, Va. : Naval Postgraduate School ; Available from National Technical Information Service, 2005. http://library.nps.navy.mil/uhtbin/hyperion/05JunMiller.pdf.
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Laxon, Seymour William Clarke. "Satellite radar altimetry of sea ice." Thesis, University College London (University of London), 1989. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.325510.
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The thesis concerns the analysis and interpretation of data from satellite borne radar altimeters over ice covered ocean surfaces. The applications of radar altimetry are described in detail and consider monitoring global climate change, the role that sea ice plays in the climate system, operational applications and the extension of high precision surface elevation measurements into areas of sea ice. The general nature of sea ice cover is discussed and a list of requirements for sea ice monitoring is provided and the capability of different satellite sensors to satisfy needs is examined. The operation of satellite borne altimeter over non-ocean surfaces is discussed in detail. Theories of radar backscatter over sea ice are described and are used to predict the radar altimeter response to different types of sea ice cover. Methods employed for analysis of altimeter data over sea ice are also described. Data from the Seasat altimeter is examined on a regional and global scale and compared with sea ice climatology. Data from the Geosat altimeter is compared with co-incident imagery from the Advanced Very High Resolution Radiometer and also from airborne Synthetic Aperture Radar. Correlations are observed between the altimeter data and imagery for the ice edge position, zones within the ice cover, new ice and leads, vast floes and the fast ice boundary. An analysis of data collected by the Geosat altimeter over a period of more than two years is used to derive seasonal and inter-annual variations in the total Antarctic sea ice extent. In addition the retrieval of high accuracy elevation measurements over sea ice areas is carried out. These data are used to produce improved maps of sea surface topography over icecovered ocean and provide evidence of the ability of the altimeter to determine sea ice freeboard directly. In addition the changing freeboard of two giant Antarctic tabular icebergs, as measured by the Geosat altimeter, is presented. As a summary the achievements are reviewed and suggestions are made towards directions for further work on present data sets and for future data from the ERS-1 satellite.
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Braatz, Barbara V. "Recent relative sea-level change in Eastern North America." Thesis, Massachusetts Institute of Technology, 1987. http://hdl.handle.net/1721.1/55310.
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Thesis (M.S.)--Joint Program in Oceanography (Massachusetts Institute of Technology, Dept. of Earth, Atmospheric, and Planetary Sciences; and the Woods Hole Oceanographic Institution), 1987.Supervised by David G. Aubrey.
Includes bibliographical references (leaves 57-61).
by Barbara Vanston Braatz.
M.S.
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Moss, Cowan Amanda. "Sea change : a sensemaking perspective on competing institutional logics." Thesis, University of Oxford, 2013. http://ora.ox.ac.uk/objects/uuid:9908f689-1de6-4562-9795-61cd00626d6d.
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In recent years, institutional theorists have been increasingly interested in institutional change, seeking to understand the contextual factors and agents responsible for alterations to existing institutional arrangements. Institutional theory’s historical focus on isomorphism has made it challenging to account for actors’ motivations to pursue change projects. It is generally believed, though, that agents are mobilized through exposure to multiple institutional logics. Recently, scholars have begun to recognize that competition among multiple logics may not quickly produce a ‘winning logic’; rather, such logics may co-exist for prolonged periods in a context of ‘institutional complexity’. The turn toward institutional complexity reveals that preoccupation with the ‘paradox of embedded agency’ has left the development of change projects themselves under-theorized: What happens when organizational actors must interpret puzzling institutional contexts and generate alternatives? In seeking to understand organizational actors’ efforts to cope with conflicting logics in a context of scientific uncertainty, this study aligns with this growing interest in institutional complexity. Drawing on concepts from sensemaking theory, this research illuminates how actors with divergent interests, enacting their organizational roles, cope with competing logics and interact around a change project that emerges as a result of their efforts at coping. It thus contributes to institutionalist understandings of institutional complexity and change and adds to an emerging body of research linking institutional theory and sensemaking. The empirical setting for this single-case study is the ‘sustainable seafood’ discourse that began in the early 1990s when the cod collapsed off North America’s eastern seaboard. Prolonged scientific uncertainty regarding the collapse made generation of preferred alternatives problematic; this resulted in lengthy sensemaking efforts by multiple stakeholder groups, drawing on different institutional logics to produce divergent and competing interpretations and action scripts. Tracing the evolution of this discourse through documents, observations, and interviews empirically reveals processes of interrelated sensemaking, and further, exposes sensegivers as bricoleurs who use institutional elements creatively to affect the sensemaking of others.
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Islam, M. Shahidul. "Relative sea-level change in Bangladesh during the Holocene." Thesis, University of St Andrews, 1997. http://hdl.handle.net/10023/15244.
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The thesis aims to reconstruct the Holocene sea-level history in Bangladesh. Detailed litho-, bio-, and chrono-stratigraphic techniques have been applied to elucidate the nature of sedimentary sequences in association with the events of the Holocene marine transgressions and regressions. Samples have been collected from two separate sites, one at Panigati near Khulna and another at Matuail near Dhaka. The study shows evidence of five periods of marine transgression, each followed by a regression, during the Holocene. Each minerogenic sediment layer indicates a marine episode and these sediments were deposited under intertidal to estuarine conditions; each peat layer is in situ and indicates a retreat of the sea. It is difficult to separate the eustatic components contributing to these relative sea-level movements, although processes operating locally and regionally are clearly evident. Two separate sea-level curves, together with possible error ranges, have been proposed for Bangladesh; since the early mid-Holocene, an average relative sea-level rise of 1.07 mm. yr -1 has been estimated. The reconstructed sea-level curves show that during the early and mid-Holocene both sedimentation and subsidence rates were much lower than during the last millennium. Differential spatio-temporal progradation and coastline movements have also been evident. The Ganges and Brahmaputra rivers have provided a continuous sediment supply but their convergence is only of recent origin. A possible hypothesis of two separate estuarine systems for these two rivers has been put forward.
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Laird, Colleen. "Sea Change: Japan's New Wave of Female Film Directors." Thesis, University of Oregon, 2013. http://hdl.handle.net/1794/12973.
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Since the mid-2000s, there has been a significant increase in female directors in Japan. Organized around the central feature of this emerging wave, this dissertation is a multifaceted project that combines historical research with reception studies, industry studies, gender studies, and formal analysis of films and marketing paratexts. In exploring the connections between film production, reception, exhibition, and auteur personas, I argue that the recent emergence of women into commercial cinema is fueled by gendered marketing tactics that seek to target contemporary female consumers. This focused gendering of auteur, product, exhibition space, and presumed spectator is changing the landscape of cinema in Japan, a process some refer to as "feminization." My dissertation rethinks the history of Japanese cinema with regards to the relationship between filmmakers as gendered bodies, distribution companies and marketing as patriarchal power structures, and the capital wielding demographic of female spectators as influential, but often neglected, consumers.2015-07-11
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Chang, Biao. "Spatial analysis of sea level rise associated with climate change." Diss., Georgia Institute of Technology, 2013. http://hdl.handle.net/1853/49062.
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Sea level rise (SLR) is one of the most damaging impacts associated with climate change. The objective of this study is to develop a comprehensive framework to identify the spatial patterns of sea level in the historical records, project regional mean sea levels in the future, and assess the corresponding impacts on the coastal communities. The first part of the study suggests a spatial pattern recognition methodology to characterize the spatial variations of sea level and to investigate the sea level footprints of climatic signals. A technique based on artificial neural network is proposed to reconstruct average sea levels for the characteristic regions identified. In the second part of the study, a spatial dynamic system model (DSM) is developed to simulate and project the changes in regional sea levels and sea surface temperatures (SST) under different development scenarios of the world. The highest sea levels are predicted under the scenario A1FI, ranging from 71 cm to 86 cm (relative to 1990 global mean sea level); the lowest predicted sea levels are under the scenario B1, ranging from 51 cm to 64 cm (relative to 1990 global mean sea level). Predicted sea levels and SST's of the Indian Ocean are significantly lower than those of the Pacific and the Atlantic Ocean under all six scenarios. The last part of this dissertation assesses the inundation impacts of projected regional SLR on three representative coastal U.S. states through a geographic information system (GIS) analysis. Critical issues in the inundation impact assessment process are identified and discussed.
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Hutchings, Jennifer Katy. "On modelling the mass of Arctic sea ice." Thesis, University College London (University of London), 2001. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.246736.
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Lamamie, de Clairac Garrido Paula. "There was a sea." Thesis, University of Iowa, 2015. https://ir.uiowa.edu/etd/1982.
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There was a sea is the resultant piece of a creative research conducted about human relationships with the element water. The dance takes us on a trip through different states of the spectrum scarcity-abundance of water around the world.
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Horton, Benjamin Peter. "Quantification of the indicative meaning of a range of Holocene sea-level index points from the western North Sea." Thesis, Durham University, 1997. http://etheses.dur.ac.uk/987/.
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Powell, Victoria Alicia. "Relative sea level change in the Forth and Tay Estuaries : past changes informing future trends." Thesis, University of Dundee, 2012. https://discovery.dundee.ac.uk/en/studentTheses/832abe7f-3917-48ad-a9e5-a66f5f57d583.
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This thesis introduces new relative sea level datasets from the Forth and Tay Estuaries dating between 1900 and 2010 and uses these to analyse sea level oscillations, surge components and to influence future sea level projections. Prior to this research, relative sea levels had not been analysed across this region. These datasets were collated and corrected using renowned methods and investigated using Shennan et al.’s (2012) GIA corrections, Torrence and Compo’s (1998) Morlet wavelet transform and Graff’s (1981) sea level maxima analysis. The relative sea level data were then used to support adaptations of two sea level projection models to 2100; the UK Climate Projections 2009 (UKCP09) probabilistic model and Vermeer and Rahmstorf’s (2009) temperature-sea level relationship projections model. These models were, in turn, used to project the impact of extreme relative sea levels on local infrastructure by 2100. This research revealed that relative sea level in the Forth and Tay Estuaries between 1900 and 2010 rose at a rate of 0.27 to 0.56 mm a-1, which is smaller than the global average of 1.7 mm a-1 (Church and White, 2011). Tidal residuals were commonly observed to be approximately 0.4 and 0.7 m at Leith and Dundee between 2003 and 2010, whilst the highest sea level maxima across 5 ports in the region ranged between 3.27 and 4.13 m above OD. Adaptions of the UKCP09 model reduced the original projections for 2100 of between 31.3 and 35.1 cm to between 24.3 and 27.5 cm above the 1990 mean. Similarly, adaptions of the Vermeer and Rahmstorf (2009) model reduced projections from 107.5 cm to between 50.9 and 54.2 cm above the 1990 mean. These adapted projections, when added to the extreme 2100 sea level calculations, suggests that the highest extreme sea level by 2100 could reach the present day quayside heights at selected locations in the Forth and Tay Estuaries. The approach and results are replicable across other regions, thereby refining projections made by previous authors.
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Holmes, Caroline Ruth. "The impact of Arctic sea ice change on midlatitude climate." Thesis, University of Reading, 2016. http://centaur.reading.ac.uk/65946/.
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Arctic sea ice loss is a robust feature of observations and of climate model projections. Amplified winter lower tropospheric warming in the Arctic relative to the global mean is associated with this ice loss. Many recent studies have addressed the possible effects of these changes on the midlatitude atmospheric circulation, particularly in the North Atlantic. These studies suggest responses including an equatorward jet shift, a negative annular mode response and changes in Rossby wave behaviour. However, there is disagreement on the magnitude, significance and even sign of these responses. Previous studies have shown the advantages of model hierarchies for understanding the atmosphere. In this thesis, experiments are conducted in HadGAM1 with simplified lower boundary conditions. Two sets of experiments are conducted, one in a zonally symmetric aquaplanet and the other in a configuration with representative northern hemisphere land masses. A wide range of sea ice profiles are imposed. The dominant response to ice removal in an aquaplanet is an equatorward jet shift, consistent with previous work. This response is moderate in magnitude for ice which does not exceed 65◦ latitude, but strongly nonlinear for greater ice extents. The zonal mean response is qualitatively similar in the asymmetric configuration, but the nature of the asymmetric response shows sensitivity to the exact ice edge location. These results have implications for understanding the impact of sea ice anomalies in past as well as present climates. Changes in surface temperature gradients, including from Arctic amplification, could affect midlatitude climate even if circulation changes are small. In particular, changes in thermal advection could alter midlatitude temperature variability and extremes. In this thesis a multiple regression model is used to investigate projected monthly temperature variance changes in a recent single model ensemble. Many robust changes, including reduced winter temperature variance in Europe, are consistent with the effect of changes in the seasonal mean temperature gradient alone.
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Thomson, Katie Hannah. "Earthquakes and sea-level change in Hokkaido, north-east Japan." Thesis, Durham University, 2009. http://etheses.dur.ac.uk/143/.
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This thesis details the results of an investigation into the pattern of relative sea-level (RSL) changes in north-east Hokkaido, Japan. The aim of the research is to better understand the importance of seismic and non-seismic processes in controlling spatial patterns of vertical land motions over a range of timescales. The main focus is on using salt-marsh sediments as a source of data to reconstruct RSL change during the current interseismic period, since c. 300 calibrated years before present (cal. yr BP). Previous research on the Pacific coast of Hokkaido suggests that this period is characterised by subsidence caused by strain accumulation on the locked part of the Pacific/North American plates. I apply foraminiferal-based methods of palaeoenvironmental reconstruction to develop, using transfer functions, quantitative reconstructions of RSL change at five sites in north-east Hokkaido. Contemporary foraminifera are zoned with respect to elevation and tidal inundation, and my preferred transfer function (a model that contains 87 samples and 24 taxa) has a prediction r2 of 0.75 and a root mean squared error of prediction of ± 0.32 m. I apply this transfer function to shallow fossil sediment sequences at five salt marshes and use a combination of 210Pb, 137Cs and tephra chronology to establish age models for the sequences. The reconstructions are consistent in demonstrating little net RSL change during the last 300-100 cal. yrs, with the exception of data from one site, Sarfutsu-toh, located on the northern tip of Hokkaido. Chronologies from two profiles developed on the Pacific coast record strong evidence for recent RSL rise since the mid-1980s, but during earlier periods of the 20th century reconstructed RSL was stable or falling. I compare my reconstructions with other direct and proxy records of land and sea-level motions. Previously published GPS and repeat levelling data indicates subsidence in south-east Hokkaido during the 20th century, although the spatial patterns and rates of change have varied. An unknown amount of this subsidence at the Kushiro tide gauge likely reflects anthropogenic activities associated with sediment compaction as well as mining-induced subsidence. An analysis of the tide-gauge records from Hokkaido show a more varied pattern of land motions, although they also confirm subsidence on the Pacific coast, close to the Kuril trench. A database of Holocene sea-level index points provides insights into longer-term millennial-scale trends in RSL. Data from six regions of Hokkaido demonstrate stable RSL close to present during the mid- and late Holocene; only the northern tip of Hokkaido (around Sarubetsu) is there evidence for a small mid-Holocene highstand of 1-3 m above present. Finally, a review of Pleistocene raised marine terrace data shows net uplift over the last c. 330 k yr, with two areas of particularly high uplift at Abashiri and on the Pacific coast near Kushiro. The evidence presented in this research demonstrates that it is incorrect to infer that the current interseismic period is characterised by subsidence. Overall, RSL has changed little in the last 300-100 cal. yrs. The subsidence recorded in the mid- and late 20th century on the Pacific coast of Hokkaido is not typical of the full interseismic period, nor can it have been sustained over Holocene or Pleistocene timescales. Limited data from previous earthquake cycles indicate that RSL was stable, rising or falling during previous interseismic intervals. These observations suggest that a representative ‘Hokkaido earthquake deformation cycle’ may not exist. Future research should better understand the controls of Quaternary volcanic activity on regional deformation patterns, and apply microfossil-based techniques to multiple earthquake cycles at sites to help define the spatial extent of land motions associated with different events.
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Taylor, Damian Russell. "An analysis of sea level change in the Severn Estuary." Thesis, University of Bristol, 1995. http://hdl.handle.net/1983/1db48ad5-36e1-495e-9459-84d2fb31357b.
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Furze, Mark Fernley Alexander. "Late Pleistocene sea-level change in the Celtic Sea : radiocarbon dated macrofauna as palaeo-water-depth indicators." Thesis, Bangor University, 2001. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.367395.
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Newton, Thomas Lee. "Holocene sea-level changes in the Falkland Islands : new insights into accelerated sea-level rise in the 20th Century." Thesis, University of Plymouth, 2017. http://hdl.handle.net/10026.1/9650.
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This thesis investigates sea-level changes in order to test the hypothesis that the main contribution to early 20th century sea-level rise was Northern Hemisphere land-based ice melt. Multiproxy sea-level reconstructions were established for the Falkland Islands, a location where models suggest sea-level rise from Northern Hemisphere ice melt produces the largest signal. The Falklands reconstruction indicated sea levels in the early 20th century accelerated compared to the long-term rate, synchronous with accelerations observed globally. The magnitude of the acceleration in the Falklands reconstruction was greater than Northern Hemisphere rates, consistent with the spatial pattern from a Northern Hemisphere melt source, but likely less than in New Zealand and Australia. It is therefore not possible rule out other contributions to the observed sea-level acceleration. The Falklands reconstruction indicated a rapid sea-level jump around 8.4 ka BP, synchronous with a jump observed in the Northern Hemisphere, which has been attributed to the sudden drainage of Laurentide proglacial lake Agassiz-Ojibway associated with the 8.2 ka BP climatic downturn. A maximum estimate of 0.89 ± 0.22 m for this jump in the Falklands is considerably less than estimates from Northern Hemisphere records. This difference could indicate additional contributions from the Southern Hemisphere are being recorded in the Northern Hemisphere signal. This thesis also focused on developing testate amoebae as sea-level indicators. In the Falklands, testate amoebae transfer functions were able to reconstruct sea level with precision (±0.08 m) comparable to diatoms (±0.07 m). However, preservation issues were indicated in the fossil testate amoebae assemblages which limits their use as tools for sea-level reconstruction. In addition, contemporary distributions of salt-marsh testate amoebae were investigated over one annual cycle. Seasonal variations in the live assemblages were observed to be asynchronous between taxa. Variations in the death assemblages were also observed which were correlated with variations in the live assemblages. This observation suggests the commonly applied assumption in palaeoenvironmental studies that analysing the death population negates temporal bias is invalid. Further research is required to investigate the impact these observed variations have on reconstructive performance.
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Purcell, Kate Clara. "Geographical change and maritime limits in the law of the sea." Thesis, University of Cambridge, 2014. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.648862.
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Agudelo, Paula A. "Analysis of spatial distribution in tropospheric and sea surface temperature trends." Thesis, Available online, Georgia Institute of Technology, 2005, 2005. http://etd.gatech.edu/theses/available/etd-04122005-120850/unrestricted/agudelo%5Fpaula%5Fa%5F200505%5Fmast.pdf.
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Thesis (M. S.)--Earth and Atmospheric Sciences, Georgia Institute of Technology, 2005.Dr. Judith A. Curry, Committee Chair ; Dr. Robert Dickinson, Committee Member ; Dr. Peter Webster, Committee Member. Includes bibliographical references.
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Rashid, Harunur. "The deep-sea record of rapid late pleistocene paleoclimate change and ice-sheet dynamics in Labrador sea sediments /." Thesis, McGill University, 2002. http://digitool.Library.McGill.CA:80/R/?func=dbin-jump-full&object_id=38540.
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Thirty eight piston cores and numerous seismic profiles collected by two R/V Marion Dufresne and several CSS Hudson cruises were examined and cores from other cruises reinterpreted in the course of this study of Late Pleistocene ice-rafting events (Heinrich events) in the Labrador Sea.In the northwestern Labrador Sea, close to the margin of the former Laurentide Ice Sheet, Heinrich layers are unusually thick. Thicknesses of up to 4.8 m result from deposition from nepheloid-flows and low-density turbidity flows and from iceberg melting. Heinrich layers formed in three stages, explained by a proposed model that also attempts to explain ice-sheet dynamics, ice-stream behavior, and sediment transfer mechanisms from the ice-sheet to the deep sea. Nepheloid-flow deposits seem to result largely from fresh water buoyantly rising out of giant turbidity currents generated at the Hudson Strait outlet.
High-resolution stratigraphic records of oxygen isotopes, concentration of total carbonate, coarse-fraction content, and magnetic susceptibility, and 70 new 14C-AMS dates establish the presence of eight Heinrich events, H0 to H6 in the northwest Labrador Sea, including a new event, termed H5a (between H5 and H6). This refined chronology shows that the recurrence intervals between Heinrich events are fairly evenly spaced, with an average of ∼7 ka, as postulated by the binge and purge model for their origin.
High-resolution oxygen isotope, concentration of total carbonate, and coarse-fraction content data suggest that both meltwater and iceberg supply increased during Heinrich events. This is the first time that increased meltwater supply by direct discharge from a major ice outlet during Heinrich events has been documented, because ice-proximal areas tend to be barren of foraminifera.
The presence of H3 between 46° and ~63°N in the Labrador Sea, previously debated, has been proved. Thickness variations for H3 were compiled on an isopach map showing a maximum thickness of 4.8 m near Hudson Strait and thinning to 30 cm in the central Labrador Sea.
H0 is present in upper Labrador slope cores, compared to other Heinrich layers which were found widely on the slope, rise, and in the basin. These findings suggest that during or prior to H0, the Hudson Strait ice-stream had retreated landward, so that glaciomarine sediments were delivered to the shelf and iceberg trajectories were following the course of the already established Labrador Current.
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Fenoglio-Marc, Luciana [Verfasser]. "Satellite geodesy for sea level and climate change / Luciana Fenoglio-Marc." Darmstadt : Universitäts- und Landesbibliothek Darmstadt, 2015. http://d-nb.info/1111909725/34.
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Lauria, Valentina. "Impacts of climate change and fisheries on the Celtic Sea ecosystem." Thesis, University of Plymouth, 2012. http://hdl.handle.net/10026.1/1166.
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Climate change and fisheries have affected marine environments worldwide leading to impacts on ecosystem structure and functioning. However there is clear evidence of spatial variability in the response of these impacts both within and among marine ecosystems. Although several studies have tried to explain the effect of these impacts on marine food webs, it is unclear how they interact, and how they may affect marine ecosystems remains an important unanswered question. This suggests the urgent need for multiple-trophic level and ecosystem-based management approaches to account for both fisheries and climate change impacts at ocean basins across the globe. Marine apex predators, such as seabirds, are vulnerable to the effects of both climate and fishing impacts, and can be used as reliable and sensitive bio-indicators of the status of the marine ecosystem. The Celtic Sea ecosystem is a productive shelf region in the Northeast Atlantic. It is characterized by high fish and invertebrate biodiversity. In addition, internationally important numbers of seabirds, such as Northern gannet Morus bassanus (L.), Manx shearwater Puffinus puffinus (B.), Common guillemot Uria aalge (P.) and Black-legged kittiwake Rissa tridactyla (L.), breed along the Celtic Sea coasts. In recent years, fisheries from across Europe have intensively exploited the Celtic Sea, leading to changes in stock structure. Moreover, the increase in annual average Sea Surface Temperature by 0.67 oC over the past two decades has altered the composition of plankton communities. These impacts, independently and in tandem, are likely to have had dramatic effects upon the Celtic Sea food web emphasizing the need to enhance our understanding of this important marine ecosystem. In this thesis the effects of climate change and fisheries on the Celtic Sea pelagic food web are evaluated, in particular focussing on the response of seabird populations. This is in part because of recent declines in the breeding success of many seabird colonies in the northeast Atlantic, particularly around the North Sea. Long-term data across four trophic levels (phytoplankton, zooplankton, mid-trophic level fish and seabirds) and different modelling approaches are used to determine factors influencing seabird productivity at different geographical scales. First, I review the direct and indirect effects of climate change and fisheries upon marine ecosystems, as well as their impacts upon marine birds. Second, I use data collected during 1986-2007 from a single seabird colony, across four trophic levels, to investigate long-term direct and indirect climate effects. The results suggest only a weak climate signal in the Celtic Sea, and this is only evident between mid-trophic level fish and certain species of seabird. Third, a similar multi-trophic level approach across three nearby regions in the southwest UK (Irish Sea, Celtic Sea, and English Channel) reveal no evidence of a bottom-up signal during the period 1991-2007. These findings are in contrast with the nearby North Sea region, where a strong bottom-up effect was found to affect seabird populations, highlighting the importance of regional-based studies across multiple trophic levels. Finally, to provide a more complete picture of the Celtic Sea, and how it might respond to changes in fisheries management and climatic variation, I use the complex tropho-dynamic ecosystem model Ecopath with Ecosim. The main focus is on how seabird biomass changes in response to the application of different fisheries regimes likely to be implemented under forthcoming reforms to the Common Fisheries Policy (e.g. the application of quotas and discard bans), as well as future climate change scenarios, in order to provide guideline support for resource management and seabird conservation in the Celtic Sea. The results suggest that some seabird guilds (gulls and some other scavengers) may be negatively affected by a reduction in discards, while other species (offshore divers) will benefit from a decrease in the fishing of pelagic fish species. Climate change is likely to have a negative impact across all trophic levels with a strong negative impact upon seabird populations. Therefore seabirds are likely to show species-specific responses to both climate variation (bottom-up effect) and changes in fishing practices, in particular our findings suggest that for some species climate may outweigh the fisheries impacts even when fisheries pressure is reduced by 50%. In summary, this study suggests that despite the generally negative impact of climate described for some regions in the Northeast Atlantic, the Celtic Sea ecosystem seems to be more resilient. However, both climate and fisheries and the interactions between these factors should be taken into account in the formulation of future management plans for the Celtic Sea ecosystem. The use of multiple-trophic level and ecosystem-based approaches over multiple spatial and temporal scales has helped to elucidate possible trophic mechanisms that are the response to future fishing and climate impacts in the Celtic Sea. The results of this study could have implications for both management plans and conservation policy.
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Stewart, Robert Neill Traill. "Regional diagenetic porosity change in Palaeocene oilfield sandstones, U.K. North Sea." Thesis, University of Glasgow, 1995. http://theses.gla.ac.uk/6327/.
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Palaeocene Montrose Group sandstones form a regionally extensive sequence of stacked sandbodies within the Central North Sea. The diagenetic sequence has been characterised as chlorite; micro-dolomite; pyrite; early carbonate concretions; dissolution of feldspars; steady precipitation of kaolinite during burial; quartz overgrowths increasing during deep burial; late calcite concretions; illite. Epigenetic chlorite, and pyrite precipitated within depositional marine porefluids (a180 -0.9%oSMOW). During the late Palaeocene-early Eocene, shortly after deposition of the Montrose Group, a dramatic sea-level fall and eastward delta progradation of the Moray group resulted in the regional meteoric flushing of the Montrose Group sands. This flushing is recorded in the isotopic signatures of early carbonate concretions, which indicate that aquifer waters had light meteoric a 180 values. Many of these concretions precipitated from bacterially-mediated reactions. This included fermentation and shallow anaerobic oxidation of hydrocarbons migrating 3km vertically from the underlying Kimmeridge Clay. Examination of 115 well logs shows that locations of vertical migration were structurally controlled, above faulted graben edges, or above thick shales along graben axes. Strontium ratios indicate that dissolution of detrital calcite supplied the calcium. Kaolinite volumes are usually 2-4%; anomalously high volumes of kaolinite (up to 12%) are found close to deltaic palaeo-shorelines and may represent precipitation during vigorous meteoric flushing of the sandstones. Kaolinite isotopic compositions throughout the Central North Sea indicate that precipitation took place within mixed meteoric-marine pore fluids, whilst surrounding marine shales compacted into a meteoric aquifer, over a temperature range of 30-8S·C. Deuterium values are unusually depleted -53 to -76, and suggest a combination of meteoric water and organic interaction. Quartz cement appears to be generally depth-controlled and forms about 4% at 8,SOOft burial. There is also a possibility of 8% quartz overgrowth adjacent to salt diapirs. Secondary porosity does not vary much with depth, always being 2-4%. This· indicates that any increase in porosity due to dissolution of feldspars has been thwarted by continued compaction and no net increase of porosity has occurred. During precipitation of late calcite concretions, pore-water a 180 was isotopically marine and C supplied by decarboxylation. This indicates that porewaters had become dominated by the introduction of evolved-marine compactional waters from overlying Palaeogene mudrocks. Late carbonate concretions contain up to 10% M nCO 3 and are enriched in radiogenic 87 Sr compared to Palaeocene shell ratios. This trend is similar to that noted in cements from the underlying Chalk. It is possible that strontium-rich fluids may have been transferred vertically into the Palaeocene from the deeper-buried Jurassic sequence. Porosity-depth profiles from conventional core analysis data in 42 wells show porosities of 22-36%, with permeabilities of 40-3,000mD at 5,700-9,200ft. The dominant controls are depositional facies, and compaction. Dewatering structures can reduce vertical permeability by lOx. Authigenic chlorite maintains high porosities, but with permeability reduced by lOx. Vertical gradients of porosity and of permeability with depth exhibit "bow curves", which· decrease at the top and base of each channel sand unit. Shorter core lengths give systematically higher rates of porosity decline, due to insufficient sampling of depositionally thick channels, whereas cores longer than 30m give gradients of 5-13%.km- 1. Porosity varies regionally, but no regional variation of decline-gradient was found.
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Jackson, Luke Peter. "Caribbean sea level change : observational analysis from millennial to decadal timescales." Thesis, University of Leeds, 2013. http://etheses.whiterose.ac.uk/5779/.
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Sea-level rise continues to be an issue of societal concern. It is a fact that millions of people live close to the coast and will be at risk both directly and indirectly from sea-level rise. Understanding the future begins in the past and so this thesis considers Holocene and modern sea-level variations in the Caribbean region, an area particularly at risk from long term sea-level rise. I construct a catalogue of 561 published Holocene sediment ages and depths, primarily fossil corals and mangrove peats. I derive probability distributions of the habitable ranges of corals and peat using modern growth and abundance records. These distributions are used to simulate realisations of sea-level position in the past. The relative sea-level (RSL) position and RSL rate are calculated at 500 year time slices to construct sub-regional sea-level histories. At each time slice, I select the realisations that fall within a 2000 year time window and calculate the least-squares estimate of RSL rate and RSL position. Results show Caribbean wide spatio-temporal RSL changes. From 7000 to 4000 cal yr BP, RSL rates were »2 mm yr−1 in the north (Cuba and Florida), »1 mm yr−1 in the east (Lesser Antilles and US Virgin Islands) and »2.5 mm yr−1 in the south west. From 4000 to 1000 cal yr BP, sea level rose between 3 (US Virgin Islands, Venezuela and Trinidad) and 5 metres (Florida, Belize). During the last 1000 years, RSL rates fell below 1 mm yr−1 and by 500 cal yr BP lay between 0 to 0.5 mm yr−1. The spatial variation between sub-regional RSL histories is also investigated by using a spherically symmetric, rotating numerical model that simulates sea-level change and vertical ground motion (VGM). I derive model RSL histories at the sub-regions in the Caribbean using a single deglaciation model and a range of earth parameters. By minimising the misfit of the model RSL curves to the data driven RSL curves, I find a representative model fit where lithospheric thickness is 71 km, upper and lower mantle viscosities are 0.5 and 10 × 1021 Pa s respectively. To find the change in sea-level rise in modern (1960 to 2012) times compared to the late Holocene, I calculate RSL and absolute sea-level (ASL) rates using 49 tide gauge records and satellite altimetry. I apply three corrections to remove seasonal and regionally coherent noise and calculate a least-squares estimate of sea-level change. Results show that present day RSL rise is up to three times greater than in the late Holocene, though there remains a small (· 1 mm yr−1) long term contribution from the last deglaciation. For individual sites, I found that variations in VGM can exacerbate long term sea-level change enhancing the risk of coastline communities.
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Edwards, Robin James. "Late Holocene relative sea level change and climate in southern Britain." Thesis, Durham University, 1998. http://etheses.dur.ac.uk/1056/.
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Caccamise, Dana John II. "Geodetic and Oceanographic Aspects of Absolute versus Relative Sea-Level Change." The Ohio State University, 2019. http://rave.ohiolink.edu/etdc/view?acc_num=osu1543357751520828.
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Li, Linghan. "Physical Controls on Ice Variability in the Bering Sea." Thesis, University of California, San Diego, 2014. http://pqdtopen.proquest.com/#viewpdf?dispub=3605848.
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This study primarily focuses on sea ice variability in the Bering Sea, and its thermodynamic and dynamic controls.
First, the seasonal cycle of sea ice variability in the Bering Sea is studied using a global fine-resolution (1/10-degree) fully-coupled ocean and sea ice model forced with reanalysis atmospheric forcing for 1980-1989. The ocean/sea-ice model consists of the Los Alamos National Laboratory Parallel Ocean Program (POP) and the Los Alamos Sea Ice Model (CICE). The modeled seasonal mean sea ice concentration strongly resembles satellite-derived observations. During winter, which dominates the annual mean, model sea ice is mainly formed in the northern Bering Sea, with the maximum ice growth rate occurring along the coast, due to cold air from northerly winds and ice motion away from the coast. South of St. Lawrence Island, winds drive sea ice to drift southwestward from the north to the southwestern ice covered region. Along the ice edge in the western Bering, ice is melted by warm ocean water, which is carried by the Bering Slope Current flowing to the northwest, resulting in the S-shaped asymmetric pattern seen in the ice edge.
Second, the year-to-year variability of sea ice in the Bering Sea for 1980-1989 is addressed. While thermodynamic processes dominate the variations in ice volume change in the Bering Sea on the large scale, dynamic processes are important locally near ice margins (both oceanic and land), where local dynamic and thermodynamic ice volume changes have opposite signs with large and similar amplitudes. The thermodynamic ice volume change is dominated by ice-air surface heat flux, which in turn is dominated by sensible heat flux, except near the southern ice edge where it is largely controlled by ocean-ice heat flux. This indicates that surface air temperature, which is specified from observations, strongly controls the ice volume tendency. Ice motion is generally consistent with winds driving the flow, except near certain straits in the north where ice motion largely follows ocean currents.
This study also addresses Greenland supraglacial lakes on top of ice and ice-dammed lakes adjacent to glaciers. Those surface lakes have been observed to fill and drain periodically, affecting the ice motion over land. This study provides observational constraints on the volume of water contained in and drained from the lakes, based on the repeat laser altimetry.
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Liski, Anja Helena. "Hold the line or give in to the sea? : deliberative citizen engagement in governance to adapt to sea level rise on the shoreline." Thesis, University of Edinburgh, 2018. http://hdl.handle.net/1842/33070.
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Shorelines, including the Inner Forth in Scotland, are facing unprecedented challenges with climate change. Rising sea levels mean that stakeholders need to work closely to deliver adaptation, such as the nature-based option of intentionally realigning shorelines landwards to give the sea more space. Drawing from workshops, interviews and surveys with citizens living on the shores of the Inner Forth, and semi-structured interviews with locally active organisations and land-owners, this thesis examines the governance context and methodological issues of citizen engagement in adaptation, with a focus on the use of participatory valuation tools. In particular, I develop citizen-oriented methodological options for integrated and deliberative valuation to address issues of inclusivity and knowledge gaps. The novelty of the deliberative valuation presented here is based on the explicit consideration of awareness gaps from both expert and local perspectives. The results show that even though emerging collaborative institutions are broadening the spectrum of stakeholders engaged in shoreline governance, they do not yet include representative groups of citizens. Empirical material presented here suggests that bridging the citizen engagement gap would potentially support the uptake of nature-based adaptation options, enhance legitimacy of decision-making processes, and bring other-regarding moral principles and biocentric values into decision-making. However, as the valuation results from the citizen workshops illustrate (in resonance with the central tenets of the Intergovernmental science-policy Platform on Biodiversity and Ecosystem Services), commonly applied valuation methods may be too narrow in their framing to capture plural values and world views. Furthermore, the ability of citizens to engage in adaptation is limited by knowledge gaps regarding the local area and the pressures it is facing. The deliberative citizen-oriented approach to valuation developed here led to the emergence of clearer priorities, improved choice model fit and participant confidence, providing empirical evidence to support the premise that deliberation builds citizens' ability to engage in adaptation. In addition to contributing empirical insights on how adaptation governance is unfolding on local scales, this thesis responds to methodological discussions on the use of valuation for citizen engagement in three main ways: 1) it demonstrates that the choice of value framings impacts the engagement outcomes; 2) it illustrates how deliberative valuation can shape citizens' attitudes towards the uptake of adaptation measures; 3) it provides evidence of the specific role that local knowledge plays in improving the outcomes of deliberative valuation.
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Tobias, Amy E. "Effects of environmental change on species : Marvacrassatella lineage and the Plio-Pleistocene record of sea level change /." Thesis, This resource online, 1998. http://scholar.lib.vt.edu/theses/available/etd-07132007-143141/.
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SUGITANI, KENICHIRO, and KOICHI MIMURA. "Redox change in sedimentary environments of Triassic bedded cherts, central Japan: possible reflection of sea-level change." Cambridge University Press, 1998. http://hdl.handle.net/2237/10289.
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Turner, Jennifer 1979. "Investigating the effects of climate change and sea level rise on the coastal processes of the Beaufort Sea, Yukon Territory." Thesis, McGill University, 2004. http://digitool.Library.McGill.CA:80/R/?func=dbin-jump-full&object_id=81448.
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High latitude areas have been identified in most GCMs as regions where global warming will appear earliest and be the greatest. Since much of Canada's north is underlain by permafrost, a warming of 3-5°C could cause widespread erosion and thermokarst. The Arctic coastal zone is particularly vulnerable, as it lies at the interface between terrestrial systems dominated by permafrost, and marine systems dominated by sea ice and wave action. This study aims at understanding some mechanisms of arctic coastal erosion, such as thermoerosional niches and block failure. The final goal of this research is to identify the areas of Herschel Island, Yukon Territory, which are likely to experience the greatest magnitude of change in the near future. This information is then coupled with a climate change scenario in order to predict future coastal erosion in the area.
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Bamberg, Audrey. "Geologic and Biologic Indicators of Climate Change in the Ross Sea, Antarctica." Fogler Library, University of Maine, 2007. http://www.library.umaine.edu/theses/pdf/BambergA2007.pdf.
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Islam, Tarikul. "Adaptation of Stagnicola palustris to Rapid Climate Change in the Baltic Sea." Thesis, Uppsala universitet, Institutionen för geovetenskaper, 2011. http://urn.kb.se/resolve?urn=urn:nbn:se:uu:diva-160850.
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Rapid climate change is one of the most pressing environmental issues in the world, with Scandinavia andthe Arctic among those projected to be most strongly affected. Faced with a changing environment,organisms may respond in three ways – by adaptation, migration or extinction. Adaptation can occurthrough phenotypic plasticity or microevolution, and while phenotypic responses to climate change arewell described, examples showing microevolution are rare. To be able to predict the effects of climatechange, an assessment of a species’ evolutionary potential to increased temperature is necessary.I studied whether snail populations subjected to a 30 year warming experiment have been able to adapt tothe new climate regimen. Two populations of Stagnicola palustris originating from areas affected bycooling water discharge from the nuclear power plant in Forsmark, Sweden (with increased watertemperatures by 4-10 °C) and two control populations from unaffected areas were used in thisexperiment. Laboratory reared F3 offspring were raised for 28 weeks in a common garden setup at fourdifferent temperature treatments (12-24 °C) and shell length, snail mass and higher survival weremeasured.Both warm-origin populations appeared able to have adapted to the increased temperatures, though bydifferent means. Snail growth showed evidence of co-gradient variation (after 6 and 18 weeks) and localadaptation (after 28 weeks) in one of the warm-origin populations. The other warm-origin population, onthe other hand, appeared to have acquired adaptation by increasing its survival to the higher temperaturescompared to the other three populations.My results suggest that organisms can adapt rapidly to a warmer environment. However, the effects ofimproved growth and survival on population fitness and persistence remain unclear and need to be studied further.
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Lewis, Jonathan P. "Holocene environmental change in coastal Denmark : interactions between land, sea and society." Thesis, Loughborough University, 2011. https://dspace.lboro.ac.uk/2134/8717.
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In this study a multiproxy approach (including sedimentary techniques, diatoms, molluscs, foraminifera, sedimentary pigments, isotopes, pollen and plant macrofossils) has been adopted to assess environmental change over the last ~9,000 years at three Danish coastal sites (Kilen, Norsminde Fjord and Korup Sø). Particular focus has been placed on periods of intense human coastal occupation, identifiable in Denmark's rich coastal archaeological record (i.e. shell midden accumulation periods), to test critically, hypotheses that changes in the marine environment were contemporary with major cultural and societal changes over the last ~9,000 years. For example, it has been proposed that a decrease in salinity was responsible for the widespread oyster decline, apparent in the Neolithic layers of a number of Danish shell middens. This hypothesis, however, remains speculative to date, lacking any high-resolution and quantitative salinity data covering the Mesolithic-Neolithic transition. Inside the agricultural era, two more phases of shell midden accumulation occur (i.e. during the Pitted Ware/Single Grave cultural period and the Iron Age), suggesting that people must have returned to the sea at these times for increased exploitation of its resources. A diatom-based salinity transfer function (WAPLS-C3 model, r2 boot = 0.923, RMSEP= 0.36 square root salinity units) based on a trans-Baltic training set has been applied to fossil diatom datasets from each site for quantitative assessment of salinity change over the study period. The multiproxy results presented in this study demonstrate a close connection between environmental change and human exploitation of marine resources over the Holocene. This relationship, however, is complex, with the individual fjord systems often exhibiting spatially different responses (i.e. variations in the sedimentary regime, salinity, productivity and nutrient status) to changes in key forcing mechanisms such as sea level change, climate change and human impact upon the catchment (following the introduction of agriculture). Environmental hypotheses for cultural change are reviewed on the basis of the evidence presented in this study. Diatomenvironmental relationships have also been modelled (using multivariate techniques) at Korup Sø and Norsminde Fjord using proxy data as ‘predictor' variables for changes in the terrestrial and marine environment. These results suggest that a variety of marine, climatic, human and catchment related processes are important in explaining a proportion of the variation in the fossil diatom datasets, but these influences tend to vary temporally throughout the profile (e.g. human impact becomes important after ~3,900 BC).
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Watcham, Emma Pearl. "Late Quaternary relative sea level change in the South Shetland Islands, Antarctica." Thesis, Durham University, 2010. http://etheses.dur.ac.uk/485/.
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Models have been inconsistent in their prediction of ice sheet volumes and extent over the Antarctic Peninsula and sub-Antarctic islands during the Last Glacial Maximum (LGM), and their contribution to sea level rise during subsequent deglaciation remains uncertain. The use of precise relative sea level (RSL) data offers great potential for inferring regional ice sheet histories, as well as helping to validate numerical models predicting future ice sheet evolution and RSL change. This thesis aims to elucidate the RSL history of the South Shetland Islands (SSIs), a sub-Antarctic archipelago peripheral to the northern Antarctic Peninsula ice sheet, by integrating evidence from isolation basins with geomorphological evidence from raised beaches. This will extend the only previously reported RSL curve from the area (Bentley et al., 2005a), which reveals a complex but poorly chronologically constrained RSL history. In addition, this work also aims to improve the understanding of the long-term tectonic influence on RSL change. Sediment cores were taken from five lakes on Fildes Peninsula, King George Island (eastern SSIs) at a range of altitudes above present sea level. Diatom, stable isotope (δ13C) and physical analyses of sediments revealed clear marine-lacustrine transitions in lakes below 16 m above mean sea level (amsl), with no marine signal above this altitude. Together with radiocarbon dates from raised beaches, a RSL curve was produced for the last 9500 14C yr BP. This curve shows a mid-Holocene RSL highstand at 15.5 m amsl between ca. 6150 and 6700 14C yr BP, preceded by a period of extremely rapid RSL rise and followed by more gradual RSL fall as a consequence of isostatic uplift in response to regional deglaciation. In addition, regional GPS surveys of raised beaches were conducted to assess the spatial pattern of glacio-isostatic rebound following deglaciation. The centre of uplift was found to closely coincide with the centre of the LGM ice sheet reconstructed by John and Sugden (1971). Beaches were modelled using polynomial trend surface analysis to constrain the spatial variability of isostatic uplift across the SSIs, which has enabled the regional extrapolation of the RSL curve across the archipelago. Finally, two independent approaches were taken to constrain the long-term tectonic uplift rate of the SSIs as 0.22-0.48 m/ka. Tectonic uplift contributes between 1.4 and 2.9 m to the reconstructed RSL highstand.
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Moseley, Gina Elaine. "Mid to late quaternary sea level change of the circum-Caribbean region." Thesis, University of Bristol, 2009. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.508171.
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Thompson, Philip Robert. "Sea surface height: A versatile climate variable for investigations of decadal change." Scholar Commons, 2012. http://scholarcommons.usf.edu/etd/4240.
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Decadal variations in climate are important, because the magnitude of sustained decadal change is often much larger than the often discussed background trends. Climate variability at interannual and longer periods is most often discussed in the context of climate modes defined by sea level pressure (SLP) and sea surface temperature (SST) patterns. However, SLP and SST are not capable descriptors of ocean dynamics. The approximately two decades of global sea surface height (SSH) measurements from satellite altimetry reveal substantial low-frequency redistributions of heat and salt in the ocean, which may or may not be related to defined climate modes. In addition, coastal sea level responds directly to synoptic variability in the atmosphere, providing long records of weather events in coastal areas. The unifying idea in the following analyses is the value and versatility of SSH from altimetry and sea level from tide gauges for investigations of decadal climate variability. Three applications of SSH and coastal sea level to the study of decadal change demonstrate the merits of using sea level for investigations of oceanic and atmospheric, episodic and continuous processes. The analyses concern a multidecadal change in storminess along the coast of the Southeast U.S., basin-scale coherent sea level variations in the western boundary of the North Atlantic, and the low-frequency response of the ocean to atmospheric forcing in the Northeast Pacific.
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Kerby, Tina. "UK fisheries, climate change and North Sea fishes : a long-term perspective." Thesis, University of East Anglia, 2013. https://ueaeprints.uea.ac.uk/47987/.
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North Sea demersal fishes and fisheries have changed over the past 100 years. To detect the main factors driving these changes, long-term data are needed. Using historical fisheries data that extend throughout the 20th century, this thesis aims to assess drivers influencing developments in fisheries as well as changes in the distribution and abundance of commercially important fishes in the North Sea. For English demersal fisheries, favourable political, technological and economical drivers were identified, inducing a vast rise in English fisheries in the first half of the 20th century; however, the same drivers, acting adversely, influenced the decline in recent decades and the emphasis of fisheries shifted from England to Scotland. Different trends in distribution were observed for North Sea whiting, turbot and brill between the 1920s and 2000s. Whiting distribution shifted westward between the late 1940s and1960s, whereas turbot nearly disappeared from the northern North Sea from the 1970s onwards. Brill distribution remained rather stable in the central and southern North Sea. The reasons for the longitudinal shift of whiting remained unclear as the relationships to two potential drivers, climate change and fishing pressure, were not strong. For turbot, the cause for the near disappearance from the northern North Sea is inconclusive. Commercial fisheries data were assessed reliable for distribution analysis when comparing commercial data of whiting, a commonly discarded species, and unbiased survey data. Whiting, compared to flatfish, is of secondary commercial importance. In areas where discrepancies occurred between commercial and survey data, higher discarding of whiting is suggested, as highly priced flatfish are caught there. This thesis demonstrates past conditions of demersal fish populations and fisheries in the North Sea and presents the effects of different drivers on them. The documented changes in fishes and fisheries contain valuable information for resetting baselines and developing appropriate management strategies.
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Thomas, Merryn Jane. "Public and expert perceptions of sea-level change on the Severn Estuary." Thesis, Cardiff University, 2013. http://orca.cf.ac.uk/59443/.
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As coastal communities become increasingly exposed to the risks posed by sea-level change, understanding their beliefs and responses becomes more important. While studies have identified differences in lay and expert understandings of climate change, little research has investigated how these groups understand sea-level change. This thesis uses a mental models approach to explore and compare expert and public perceptions of sea-level change on the Severn Estuary, a threatened coastal environment in the southwest of the United Kingdom. A three-phase methodology is adopted. First, expert perceptions are investigated through semi-structured interviews, probability elicitations and cognitive mapping with experts in the field of sea-level change on the Severn Estuary (N=11). Second, public perceptions are investigated through mental models interviews that include a semi-structured discussion, a picture sorting task, and a cognitive mapping session (N=20). Third, perceptions raised during public interviews are explored by way of a wider survey of members of the public living around the Severn Estuary (N=359). These perceptions are then compared and contrasted. A grounded approach is utilised to explore themes emerging from expert and public qualitative interviews, while regression analyses explore the relationships between themes explored in the quantitative public survey. Results show areas of public understanding consistent with expert understandings: most public respondents think that sea levels will rise, leading to increased flooding and property damage. However, the Severn Estuary public does not feel well informed about sea-level change, and there are a number of key differences between expert and public perceptions. For example, there is low public salience of some of the key drivers of sea-level change and its indirect impacts. Perceptions are influenced by many factors including information sources, the ways in which individuals think about the future, and the biases that they hold. Many findings are consistent with climate change research more generally. For example, respondents tend to express low concern about sea-level change in relation to other matters such as the economy; they feel detached from the issue, seeing it as something that will happen in the future to other people; and they perceive that neither the causes of nor responses to sea-level change are their responsibility. From an applied perspective, the study fills a research gap in how the Severn Estuary public perceives sea-level change in their region, and provides insights into how it might best be communicated. From a methodological perspective, the study illustrates the utility of using mixed methods, interdisciplinary approaches for investigating public and expert perceptions of specific climate change risks.
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Eriksson, Hägg Hanna. "Nitrogen land-sea fluxes in the Baltic Sea catchment : Empirical relationships and budgets." Doctoral thesis, Stockholms universitet, Institutionen för tillämpad miljövetenskap (ITM), 2010. http://urn.kb.se/resolve?urn=urn:nbn:se:su:diva-32493.
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In this thesis empirical relationships and modeling tools are used to describe the relationship between human activities and meso- and large scale riverine N fluxes from land to sea. On a large scale Paper I showed that by only having knowledge about human population size and runoff one can estimate the riverine export of DIN (r2= 0.76). In Paper II we included two other important anthropogenic N inputs, i.e. atmospheric deposition and primary emission (PE) from animals. In most of the catchments the PE from animals were larger than the PE from humans. Hence, development of livestock is important and increased animal protein consumption by humans might increase the riverine N export. Scenario analysis (Paper II) show that climate change is expected to both decrease and increase the riverine N export depending on which part of the catchment is modeled. In the southern and eastern parts of the Baltic Sea catchment there is large potential for N reductions from point sources (Papers III & V). The diffuse sources are more difficult to decrease and a reduction of mineral fertilizer does not always lead to reduced N loadings because the agricultural systems can buffer even a slight surplus (Paper III). There is inertia in the catchments which can be seen in for example in the northern part of the catchment. Here atmospheric N deposition is almost as high as in the southern part but the nitrogen flux from these rivers is not elevated. These northern river catchments have N exports of the same magnitude as the natural background (Paper IV), indicating that the atmospheric N deposition is retained in the system and probably taken up by N limited boreal forests. However, important reductions can be achieved in the agricultural sector by detailed management of the planted land and animal manure. The highest sensitivity is in catchments with high animal density and high specific discharge, primarily draining to Kattegat and Danish Straits (Paper II & IV).At the time of doctoral dissertation the following publications were unpublished and had a status as follows: Paper 2: Manuscript. Paper 4: Manuscript
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Botella, Albéric. "Past and Future Sea-Level Changes in French Polynesia." Thesis, Université d'Ottawa / University of Ottawa, 2015. http://hdl.handle.net/10393/33392.
Full textAbstract:
Among the various adverse effects of climate change, sea-level rise is expected to increase the severity and frequency of flooding events impacting the vulnerable, low-lying islands of French Polynesia. It has long been understood that sea-level changes are not spatially uniform, yet this aspect is not taken into account in the decision-making. Notably, no projections of future sea level have been produced specifically for this region so far, partly because the processes driving sea-level changes remain poorly constrained. To approach the issue, we present a detailed reconstruction of sea-level changes for the mid-to-late Holocene, based on the observation of coral proxies. This dataset is then used to calibrate a sea-level model in order to estimate the contribution of glacial isostatic adjustment to regional sea-level changes and to infer past variations in global ice volume. Building upon this baseline and exploiting recent outputs of climate models, we project that in a “worst-case” scenario, sea level would rise 1.05 meters by 2100 in French Polynesia, exceeding the value adopted in the French adaptation strategy by 0.45 meters. We conclude that spatial variability of sea-level rise should be considered in future risk studies for this and other regions.
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Jones, Sarah Louise. "Sea-level changes in south east England and northern France." Thesis, Queen Mary, University of London, 2002. http://qmro.qmul.ac.uk/xmlui/handle/123456789/28591.
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The aim of the research was to provide new sea-level index points,with the intention of identifying any cross-channel similarities and comparing the results to geophysical models of relative sea-level change. The research successfully provided new sea-level index points from the Pevensey levels, East Sussex; the Canche Estuary, Pas de Calais and the Somme Estuary, Picardie, which were validated using stratigraphic pollen,diatom,foraminiferal snd AMS radiocarbon dating analysis. The results pointed to the presence of a coastal barrier thoughout the mid-Holocene at Pevensey and the Somme which complicated the pattern of coastal sedimentation observed at these sites. A clear pattern of barrier de-stabilisation can be seen to take place either side of the Channel c.3000 years cal BP. A cross-channel comparison identified three similar transgressive events either side of the English Channel, c. 5500, 3000 and 2200 cal years BP. The observed results from each site were then compared to the predicted data( Lambeck pers.comm) .in order to determine whether the observational data could be used to validate the modelled data. The comparisons showed that for the sites in south east England the modelled data tended to over-predict sea-level rise for the mid-t o late- Holocene whereas the model tended to under-predict sea-level rise for the sites in northern France. The new observational data which the research provided could be used to further validate Lambeck's (1990,1997) geophysical model. The effects of local coastal processes, such as tidal range, crustal subsidence and barrier-dynamics were used to aid the comparisons between the pattern of sediment deposition and thus the sea-level signals. These findings suggested that reconstructions should be restricted to sites at an estuary-sized scale.
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Williams, Erica. "Aquatecture : architectural adaptation to rising sea levels." [Tampa, Fla] : University of South Florida, 2009. http://purl.fcla.edu/usf/dc/et/SFE0003290.
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