Journal articles on the topic 'Atmospheric sciences not elsewhere classified'
To see the other types of publications on this topic, follow the link: Atmospheric sciences not elsewhere classified.
Create a spot-on reference in APA, MLA, Chicago, Harvard, and other styles
Consult the top 50 journal articles for your research on the topic 'Atmospheric sciences not elsewhere classified.'
Next to every source in the list of references, there is an 'Add to bibliography' button. Press on it, and we will generate automatically the bibliographic reference to the chosen work in the citation style you need: APA, MLA, Harvard, Chicago, Vancouver, etc.
You can also download the full text of the academic publication as pdf and read online its abstract whenever available in the metadata.
Browse journal articles on a wide variety of disciplines and organise your bibliography correctly.
1
Partanen, A. I., A. Laakso, A. Schmidt, H. Kokkola, T. Kuokkanen, J. P. Pietikäinen, V. M. Kerminen, K. E. J. Lehtinen, L. Laakso, and H. Korhonen. "Climate and air quality trade-offs in altering ship fuel sulfur content." Atmospheric Chemistry and Physics 13, no. 23 (December 12, 2013): 12059–71. http://dx.doi.org/10.5194/acp-13-12059-2013.
Full textAbstract:
Abstract. Aerosol particles from shipping emissions both cool the climate and cause adverse health effects. The cooling effect is, however, declining because of shipping emission controls aiming to improve air quality. We used an aerosol-climate model ECHAM-HAMMOZ to test whether by altering ship fuel sulfur content, the present-day aerosol-induced cooling effect from shipping could be preserved, while at the same time reducing premature mortality rates related to shipping emissions. We compared the climate and health effects of a present-day shipping emission scenario (ship fuel sulfur content of 2.7%) with (1) a simulation with strict emission controls in the coastal waters (ship fuel sulfur content of 0.1%) and twofold the present-day fuel sulfur content (i.e. 5.4%) elsewhere; and (2) a scenario with global strict shipping emission controls (ship fuel sulfur content of 0.1% in coastal waters and 0.5% elsewhere) roughly corresponding to international agreements to be enforced by the year 2020. Scenario 1 had a slightly stronger aerosol-induced effective radiative forcing (ERF) from shipping than the present-day scenario (−0.43 W m−2 vs. −0.39 W m−2) while reducing premature mortality from shipping by 69% (globally 34 900 deaths avoided per year). Scenario 2 decreased the ERF to −0.06 W m−2 and annual deaths by 96% (globally 48 200 deaths avoided per year) compared to present-day. Our results show that the cooling effect of present-day emissions could be retained with simultaneous notable improvements in air quality, even though the shipping emissions from the open ocean clearly have a significant effect on continental air quality. However, increasing ship fuel sulfur content in the open ocean would violate existing international treaties, could cause detrimental side-effects, and could be classified as geoengineering.
2
Buenrostro Mazon, S., I. Riipinen, D. M. Schultz, M. Valtanen, M. Dal Maso, L. Sogacheva, H. Junninen, T. Nieminen, V. M. Kerminen, and M. Kulmala. "Classifying previously undefined days from eleven years of aerosol-particle-size distribution data from the SMEAR II station, Hyytiälä, Finland." Atmospheric Chemistry and Physics 9, no. 2 (January 28, 2009): 667–76. http://dx.doi.org/10.5194/acp-9-667-2009.
Full textAbstract:
Abstract. Studies of secondary aerosol-particle formation depend on identifying days in which new particle formation occurs and, by comparing them to days with no signs of particle formation, identifying the conditions favourable for formation. Continuous aerosol size distribution data has been collected at the SMEAR II station in a boreal forest in Hyytiälä, Finland, since 1996, making it the longest time series of aerosol size distributions available worldwide. In previous studies, the data have been classified as particle-formation event, nonevent, and undefined days, with almost 40% of the dataset classified as undefined. In the present study, eleven years (1996–2006) of undefined days (1630 days) were reanalyzed and subdivided into three new classes: failed events (37% of all previously undefined days), ultrafine-mode concentration peaks (34%), and pollution-related concentration peaks (19%). Unclassified days (10%) comprised the rest of the previously undefined days. The failed events were further subdivided into tail events (21%), where a tail of a formation event presumed to be advected to Hyytiälä from elsewhere, and quasi events (16%) where new particles appeared at sizes 3–10 nm, but showed unclear growth, the mode persisted for less than an hour, or both. The ultrafine concentration peaks days were further subdivided into nucleation-mode peaks (24%) and Aitken-mode peaks (10%), depending on the size range where the particles occurred. The mean annual distribution of the failed events has a maximum during summer, whereas the two peak classes have maxima during winter. The summer minimum previously found in the seasonal distribution of event days partially offsets a summer maximum in failed-event days. Daily-mean relative humidity and condensation sink values are useful in discriminating the new classes from each other. Specifically, event days had low values of relative humidity and condensation sink relative to nonevent days. Failed-event days possessed intermediate condensation sink and relative humidity values, whereas both ultrafine-mode peaks and, to a greater extent, pollution-related peaks had high values of both, similar to nonevent days. Using 96-h back trajectories, particle-size concentrations were plotted as a function of time the trajectory spent over land. Increases in particle size and number concentration during failed-event days were similar to that during the later stages of event days, whereas the particle size and number concentration for both nonevent and peaks classes did not increase as fast as for event and failed events days.
3
Read, Peter L., and Sebastien Lebonnois. "Superrotation on Venus, on Titan, and Elsewhere." Annual Review of Earth and Planetary Sciences 46, no. 1 (May 30, 2018): 175–202. http://dx.doi.org/10.1146/annurev-earth-082517-010137.
Full textAbstract:
The superrotation of the atmospheres of Venus and Titan has puzzled dynamicists for many years and seems to put these planets in a very different dynamical regime from most other planets. In this review, we consider how to define superrotation objectively and explore the constraints that determine its occurrence. Atmospheric superrotation also occurs elsewhere in the Solar System and beyond, and we compare Venus and Titan with Earth and other planets for which wind estimates are available. The extreme superrotation on Venus and Titan poses some difficult challenges for numerical models of atmospheric circulation, much more difficult than for more rapidly rotating planets such as Earth or Mars. We consider mechanisms for generating and maintaining a superrotating state, all of which involve a global meridional overturning circulation. The role of nonaxisymmetric eddies is crucial, however, but the detailed mechanisms may differ between Venus, Titan, and other planets.
4
WALTON, JOHN K., and DAVID TIDSWELL. "‘Classified at random by veritable illiterates’: the taking of the Spanish census of 1920 in Guipúzcoa province." Continuity and Change 20, no. 2 (August 2005): 287–313. http://dx.doi.org/10.1017/s0268416005005503.
Full textAbstract:
This article offers an approach through administrative and cultural history to the problems associated with gathering and processing data for the Spanish national census of 1920, and by implication for earlier Spanish censuses. It focuses on the Basque province of Guipúzcoa, making use of correspondence between the central statistical office in Madrid, the provincial jefe de estadística and the localities, and of reports on three problematic towns within the province. The issues that emerge regarding ‘undercounting’, the definition of administrative boundaries and the classification of demographic characteristics are set in the wider context of census-taking practices and problems elsewhere in Spain and in other cultures.
5
Keys, Patrick W., Rekha Warrier, Ruud J. van der Ent, Kathleen A. Galvin, and Randall B. Boone. "Analysis of Kenya’s Atmospheric Moisture Sources and Sinks." Earth Interactions 26, no. 1 (January 2022): 139–50. http://dx.doi.org/10.1175/ei-d-21-0016.1.
Full textAbstract:
Abstract Achievement of the United Nations Sustainable Development Goals (SDGs) is contingent on understanding the potential interactions among human and natural systems. In Kenya, the goal of conserving and expanding forest cover to achieve SDG 15 “Life on Land” may be related to other SDGs because it plays a role in regulating some aspects of Kenyan precipitation. We present a 40-yr analysis of the sources of precipitation in Kenya and the fate of the evaporation that arises from within Kenya. Using MERRA-2 climate reanalysis and the Water Accounting Model 2 layers, we examine the annual and seasonal changes in moisture sources and sinks. We find that most of Kenya’s precipitation originates as oceanic evaporation but that 10% of its precipitation originates as evaporation within Kenya. This internal recycling is concentrated in the mountainous and forested Kenyan highlands, with some locations recycling more than 15% of evaporation to Kenyan precipitation. We also find that 75% of Kenyan evaporation falls as precipitation elsewhere over land, including 10% in Kenya, 25% in the Democratic Republic of the Congo, and around 5% falling in Tanzania and Uganda. Further, we find a positive relationship between increasing rates of moisture recycling and fractional forest cover within Kenya. By beginning to understand both the seasonal and biophysical interactions taking place, we may begin to understand the types of leverage points that exist for integrated atmospheric water cycle management. These findings have broader implications for disentangling environmental management and conservation and have relevance for large-scale discussions about sustainable development.
6
Masaki, Motofumi, and Akira Koizumi. "Demographic characteristics and their genetic implications in a small island." Journal of Biosocial Science 20, no. 2 (April 1988): 225–34. http://dx.doi.org/10.1017/s0021932000017454.
Full textAbstract:
SummaryThe family registration records from a village population in a small island of Japan are used to assess the effect of demographic differentiation within a population on genetic measures. When the couples studied are classified by birth cohorts and origins, wives of the couples where one spouse came from elsewhere were older at marriage and had a shorter duration of marriage or registration than wives where both spouses were natives of the village. The mean number of offspring is statistically smaller in the former except for the latest cohort, due mainly to out-migration during the reproductive ages which also resulted in low rates of marriage among the offspring within the village. This leads to a small effective population size and an increased likelihood of genetic drift in the overall population.
7
Gong, Maoguo, Yuelei Yang, Tao Zhan, Xudong Niu, and Shuwei Li. "A Generative Discriminatory Classified Network for Change Detection in Multispectral Imagery." IEEE Journal of Selected Topics in Applied Earth Observations and Remote Sensing 12, no. 1 (January 2019): 321–33. http://dx.doi.org/10.1109/jstars.2018.2887108.
Full text
8
Melott, Adrian L., Brian C. Thomas, and Brian D. Fields. "Climate change via CO2 drawdown from astrophysically initiated atmospheric ionization?" International Journal of Astrobiology 19, no. 5 (May 28, 2020): 349–52. http://dx.doi.org/10.1017/s1473550420000117.
Full textAbstract:
AbstractMotivated by the occurrence of a moderately nearby supernova near the beginning of the Pleistocene, possibly as part of a long-term series beginning in the Miocene, we investigated whether nitrate rainout resulting from the atmospheric ionization of enhanced cosmic ray flux could have, through its fertilizer effect, initiated carbon dioxide drawdown. Such a drawdown could possibly reduce the greenhouse effect and induce the climate change that led to the Pleistocene glaciations. We estimate that the nitrogen flux enhancement onto the surface from an event at 50 pc would be of order 10%, probably too small for dramatic changes. We estimate deposition of iron (another potential fertilizer) and find it is also too small to be significant. There are also competing effects of opposite sign, including muon irradiation and reduction in photosynthetic yield caused by UV increase from stratospheric ozone layer depletion, leading to an ambiguous result. However, if the atmospheric ionization induces a large increase in the frequency of lightning, as argued elsewhere, the amount of nitrate synthesis should be much larger, dominate over the other effects and induce the climate change. More work needs to be done to clarify the effects on lightning frequency.
9
Tadaki, Marc, Jennifer Salmond, and Richard Le Heron. "Applied climatology." Progress in Physical Geography: Earth and Environment 38, no. 4 (January 23, 2014): 392–413. http://dx.doi.org/10.1177/0309133313517625.
Full textAbstract:
Applied climatology has long been a niche domain, straddling the intersection between the social and natural sciences and populated largely by geographers explicitly interested in reframing human activities around climate. As human-atmospheric relations become increasingly embedded within institutions of governance, new narratives of and for applied climatology are emerging to champion particular atmospheric objects, orientations, practices and institutions into positions of policy relevance and investment priority. This paper attempts to understand these intersecting politics of ‘climate and society’ research by situating their emergence through three lenses of inquiry. First, we explore the historical disciplinary work of ‘application’ in geographical climatology, paying particular attention to how ‘relevance’ has been understood and practised. Second, we reassemble a missed disciplinary conversation about ideology in applied geography, and link this to definitions and rationales for applied climatology. Third, we explore five recent thematic engagements in applied climatology, to generate thinking about the institutions and practices of assembling climate in new circles of ‘application’, policy and elsewhere. The ‘applications’ that climatologists choose to pursue – and the ways in which they pursue them – are deeply political questions that reproduce decision-making logics, funding rationalities, notions of expertise and problem framings. In conclusion, we argue that, rather than understanding ‘climate’ and ‘society’ as stable entities with standard (e.g. quantitative) practices or modes of association, we might instead concern ourselves with the practices of assembling human-atmospheric relations.
10
Taylor, Marc H., Martin Losch, Manfred Wenzel, and Jens Schröter. "On the Sensitivity of Field Reconstruction and Prediction Using Empirical Orthogonal Functions Derived from Gappy Data." Journal of Climate 26, no. 22 (October 29, 2013): 9194–205. http://dx.doi.org/10.1175/jcli-d-13-00089.1.
Full textAbstract:
Abstract Empirical orthogonal function (EOF) analysis is commonly used in the climate sciences and elsewhere to describe, reconstruct, and predict highly dimensional data fields. When data contain a high percentage of missing values (i.e., gappy), alternate approaches must be used in order to correctly derive EOFs. The aims of this paper are to assess the accuracy of several EOF approaches in the reconstruction and prediction of gappy data fields, using the Galapagos Archipelago as a case study example. EOF approaches included least squares estimation via a covariance matrix decomposition [least squares EOF (LSEOF)], data interpolating empirical orthogonal functions (DINEOF), and a novel approach called recursively subtracted empirical orthogonal functions (RSEOF). Model-derived data of historical surface chlorophyll-a concentrations and sea surface temperature, combined with a mask of gaps from historical remote sensing estimates, allowed for the creation of true and observed fields by which to gauge the performance of EOF approaches. Only DINEOF and RSEOF were found to be appropriate for gappy data reconstruction and prediction. DINEOF proved to be the superior approach in terms of accuracy, especially for noisy data with a high estimation error, although RSEOF may be preferred for larger data fields because of its relatively faster computation time.
11
Dall’Amico, Mauro, and Joseph Egger. "Empirical Master Equations. Part I: Numerical Properties." Journal of the Atmospheric Sciences 64, no. 9 (September 1, 2007): 2981–95. http://dx.doi.org/10.1175/jas3992.1.
Full textAbstract:
Abstract In the atmospheric sciences, master equations are mainly used in a discrete time approximation to provide forecasts of the probability density function in a discretized phase space spanned by a few climate variables. The coefficients of an empirical master equation (EME) are estimated from the relative frequencies of transitions observed in time series of the variables. The quality of an EME depends on, among other things, the length and time resolution of the available time series. In this part of the paper, these dependencies are studied on the basis of data from the three-component Lorenz model with additional white noise forcing. Thus, time series of almost any length and time resolution can be generated easily, and probability density forecasts can be compared directly with the evolution of an ensemble of points. Useful results are obtained by partitioning the phase space into several hundred cells of equal grid size. The authors find that a threshold length of the time series exists beyond which improvements in the performance of the EME are hard to detect. It is even more surprising that the performance deteriorates with reduction of the time step. This is due to an increase in numerical diffusion. The choice of the dimensionality and the selection of the variables of the EME are very important. The results of this part of the paper provide useful guidelines for any application of the EME in the atmospheric sciences and elsewhere. The second part of the paper illustrates the usefulness of these guidelines through applications to stratospheric dynamics.
12
Edwards, Thomas W. D., Brent B. Wolfe, and Glen M. Macdonald. "Influence of Changing Atmospheric Circulation on Precipitation δ18O–Temperature Relations in Canada during the Holocene." Quaternary Research 46, no. 3 (November 1996): 211–18. http://dx.doi.org/10.1006/qres.1996.0061.
Full textAbstract:
Postglacial precipitation δ18O history has been reconstructed for two regions of Canada. Long-term shifts in the oxygen-isotope composition of annual precipitation (δ18Op) in southern Ontario appear to have occurred with a consistent isotope–temperature relation throughout the past 11,500 14C yr. The modern isotope–temperature relation in central Canada near present boreal treeline evidently became established between 5000 and 4000 years ago, although the relation during the last glacial maximum and deglaciation may also have been similar to present. In the early Holocene, however, unusually high δ18Op apparently persisted, in spite of low temperature locally, probably associated with high zonal index. A rudimentary sensitivity analysis suggests that a small reduction in distillation of moisture in Pacific air masses traversing the western Cordillera, perhaps accompanied by a higher summer:winter precipitation ratio, could have been responsible for the observed effect. Equivalent isotope–temperature “anomalies” apparently occurred elsewhere in western North America in response to changing early-Holocene atmospheric circulation patterns, suggesting that a time-slice map of δ18Op for North America during this period might provide a useful target for testing and validation of atmospheric general circulation model simulations using isotopic water tracers.
13
Rhee, Seongha, and Hyun Jung Koo. "Multifaceted gustation." Food and terminology 23, no. 1 (November 10, 2017): 38–65. http://dx.doi.org/10.1075/term.23.1.02rhe.
Full textAbstract:
Korean has a large number of taste terms and the paradigm is continuously expanding since the lexicalization operates systematically on a few robust principles. Based on the taste terms collected from lexicons, dictionaries, web-postings, and elsewhere, we classified the terms and analyzed the lexicalization patterns. In addition to the widely-known five classes of tastes, i.e., sweet, salty, sour, bitter and umami, Korean has three more classes in the basic category, i.e., pungent, fishy and bland. A large number of tactile sensory words to describe the touch sensations in the mouth at the tasting event and expressions denoting characteristic food texture and mastication also join in creating a rich taste vocabulary. The Korean taste lexicalization system is equipped with the means to signal diverse aspects of gustatory sensation, i.e., intensity, depth, purity and duration. Among such means are vowel polarity, consonantal sound symbolism, reduplication and onomatopoeia. The systematicity of taste lexicalization contributes to the plasticity of the paradigm, making the Korean taste vocabulary one of the most productive and elaborate paradigms.
14
Riffkin, Penny A., Paul E. Quigley, Fiona J. Cameron, Mark B. Peoples, and Janice E. Thies. "Annual nitrogen fixation in grazed dairy pastures in south-western Victoria." Australian Journal of Agricultural Research 50, no. 2 (1999): 273. http://dx.doi.org/10.1071/a98034.
Full textAbstract:
Amounts of biologically fixed nitrogen (kg N/ha) were determined in grazed dairy pastures in 3 different areas of south-western Victoria over 12 months between October 1995 and 1996 using measurements of pasture growth, botanical composition, and the 15N natural abundance of white clover (Trifolium repens) and non-legume components. Estimates of the amounts of N fixed, based on N in clover shoots, were similar in each pasture (11, 16, and 18 kg N/ha.year), despite different environmental and management conditions. These on-farm determinations were low compared with experimental studies on N fixation by white clover undertaken in New Zealand (224–291 kg N/ha.year) and elsewhere in Australia (44–135 kg N/ha). Low fixation levels were attributed to low pasture yields (average 8.2 t dry matter (DM)/ha.year) and poor legume content in the swards (average 8%). Despite this, most of the white clover N was derived from atmospheric N2 (65%), and therefore, N fixation could potentially be playing an important role in the N economy of milk production on these farms.
15
McIver, E. E. "Paleobotanical evidence for ecosystem disruption at the Cretaceous-Tertiary boundary from Wood Mountain, Saskatchewan, Canada." Canadian Journal of Earth Sciences 36, no. 5 (May 1, 1999): 775–89. http://dx.doi.org/10.1139/e97-112.
Full textAbstract:
A continuous, subsurface Cretaceous-Tertiary boundary section, including the boundary clay within an 87 cm thick lignite, has been recovered from a core hole near Wood Mountain, Saskatchewan, Canada. The lignite-encompassed clay layer with geochemical anomaly indicates that peat deposition was continuous across the boundary. Core data indicate that, locally, a pre-boundary, conifer-dominated swamp was abruptly replaced by an angiosperm-dominated, herbaceous wetland. Sudden extermination of the dominant forest elements indicates mass kill at the level of the boundary and supports the theory of extraterrestrial impact accompanied by catastrophic destruction. Devastation of the standing vegetation may have been caused by one or more of the killing agents predicted to have accompanied impact, including freezing temperatures caused by atmospheric dust, acid rain, thermal pulse, and shock waves. There is no evidence supporting wildfires as a killing agent. Vegetational change apparent within the boundary interval is consistent with observations elsewhere in the Western Interior of North America of abrupt replacement of an ecosystem. Early Paleocene reestablishment of the cypress swamp vegetation is calculated to have taken from 1 to 5 millennia.
16
Hu, Deng, Tian, and Zhao. "A Compensation Method for a Time–Space Variant Atmospheric Phase Applied to Time-Series GB-SAR Images." Remote Sensing 11, no. 20 (October 10, 2019): 2350. http://dx.doi.org/10.3390/rs11202350.
Full textAbstract:
An atmospheric effect is a main error source that affects interferometric measurements. When a ground-based multiple-input multiple-output (GB-MIMO) radar, i.e., a specific type of GBsynthetic aperture radar (GB-SAR), was utilized to continuously monitor an open-pit mine, the interferometric phases of some interferograms were complexly space-variant due to time-variant weather conditions. The conventional method of atmospheric phase (AP) compensation was no longer applicable. This paper proposes an improved compensation method of a time-space variant AP applied to time-series GB-SAR images. The permanent scatterers (PSs) were classified into three types based on their different spatial properties: The noise-dominant PS (NPS), the deformationdominant PS (DPS), and the atmospheric effect-dominant PS (APS). The NPSs were firstly rejected based on the differential phase analysis of neighboring PSs. The DPSs were then rejected based on the cluster partition and selection. With the APSs, the space-variant AP was estimated with a spatial interpolation. To validate the feasibility of the proposed method, short-term and long-term experimental datasets were processed. Comparisons with a conventional method proved that the proposed method can well reduce AP errors and avoid the misunderstanding of motional areas.
17
Rao, Suryachandra A., B. N. Goswami, A. K. Sahai, E. N. Rajagopal, P. Mukhopadhyay, M. Rajeevan, S. Nayak, et al. "Monsoon Mission: A Targeted Activity to Improve Monsoon Prediction across Scales." Bulletin of the American Meteorological Society 100, no. 12 (December 1, 2019): 2509–32. http://dx.doi.org/10.1175/bams-d-17-0330.1.
Full textAbstract:
Abstract In spite of the summer monsoon’s importance in determining the life and economy of an agriculture-dependent country like India, committed efforts toward improving its prediction and simulation have been limited. Hence, a focused mission mode program Monsoon Mission (MM) was founded in 2012 to spur progress in this direction. This article explains the efforts made by the Earth System Science Organization (ESSO), Ministry of Earth Sciences (MoES), Government of India, in implementing MM to develop a dynamical prediction framework to improve monsoon prediction. Climate Forecast System, version 2 (CFSv2), and the Met Office Unified Model (UM) were chosen as the base models. The efforts in this program have resulted in 1) unparalleled skill of 0.63 for seasonal prediction of the Indian monsoon (for the period 1981–2010) in a high-resolution (∼38 km) seasonal prediction system, relative to present-generation seasonal prediction models; 2) extended-range predictions by a CFS-based grand multimodel ensemble (MME) prediction system; and 3) a gain of 2-day lead time from very high-resolution (12.5 km) Global Forecast System (GFS)-based short-range predictions up to 10 days. These prediction skills are on par with other global leading weather and climate centers, and are better in some areas. Several developmental activities like coupled data assimilation, changes in convective parameterization, cloud microphysics schemes, and parameterization of land surface processes (including snow and sea ice) led to the improvements such as reducing the strong model biases in the Indian summer monsoon simulation and elsewhere in the tropics.
18
Houssos, E. E., C. J. Lolis, and A. Bartzokas. "The main characteristics of atmospheric circulation associated with fog in Greece." Natural Hazards and Earth System Sciences 9, no. 6 (November 12, 2009): 1857–69. http://dx.doi.org/10.5194/nhess-9-1857-2009.
Full textAbstract:
Abstract. The characteristics of the atmospheric circulation over Europe and the Mediterranean associated with the formation and the dissipation of fog in Greece are examined. The data used consists of: i) 3-hourly meteorological observations recorded at 16 meteorological stations in Greece and ii) daily (00:00 UTC) 2.5×2.5 grid point values of mean sea-level pressure, 500 hPa geopotential height, 850 hPa and 500 hPa air temperatures and 1000–500 hPa thickness over Europe for the period 1957–2002. 1055 fog events are extracted from the 3-hourly meteorological observations. A specific methodology scheme including S-mode Factor Analysis and k-means Cluster Analysis is applied to the grid point data sets for the first day of a fog event (D day), the day prior to D day (D-1 day) and the day that follows the last day of a fog event (END day) and the 1055 evolutions of the atmospheric circulation associated with fog events in Greece are classified into 10 clusters. The mean patterns of MSL Pressure, 850 hPa and 500 hPa air temperatures, 1000–500 hPa thickness and 500 hPa geopotential height show that in most of the clusters, the presence of anticyclonic conditions over the Balkans, a warm front passage, or a weak, humid southerly flow induced by the presence of a shallow depression over the western Mediterranean favor fog formation in Greece, while the dissipation of fog occurs when drier air masses are transferred over the Balkans. The main differences among the 10 clusters refer to the exact position, the intensity and the specific evolution of the surface and the upper air systems, the season of their predominance and the area of the Greek territory that mainly refer to.
19
Conesa, Francesc C., Hector A. Orengo, Agustín Lobo, and Cameron A. Petrie. "An Algorithm to Detect Endangered Cultural Heritage by Agricultural Expansion in Drylands at a Global Scale." Remote Sensing 15, no. 1 (December 22, 2022): 53. http://dx.doi.org/10.3390/rs15010053.
Full textAbstract:
This article presents AgriExp, a remote-based workflow for the rapid mapping and monitoring of archaeological and cultural heritage locations endangered by new agricultural expansion and encroachment. Our approach is powered by the cloud-computing data cataloguing and processing capabilities of Google Earth Engine and it uses all the available scenes from the Sentinel-2 image collection to map index-based multi-aggregate yearly vegetation changes. A user-defined index threshold maps the first per-pixel occurrence of an abrupt vegetation change and returns an updated and classified multi-temporal image aggregate in almost-real-time. The algorithm requires an input vector table such as data gazetteers or heritage inventories, and it performs buffer zonal statistics for each site to return a series of spatial indicators of potential site disturbance. It also returns time series charts for the evaluation and validation of the local to regional vegetation trends and the seasonal phenology. Additionally, we used multi-temporal MODIS, Sentinel-2 and high-resolution Planet imagery for further photo-interpretation of critically endangered sites. AgriExp was first tested in the arid region of the Cholistan Desert in eastern Pakistan. Here, hundreds of archaeological mound surfaces are threatened by the accelerated transformation of barren lands into new irrigated agricultural lands. We have provided the algorithm code with the article to ensure that AgriExp can be exported and implemented with little computational cost by academics and heritage practitioners alike to monitor critically endangered archaeological and cultural landscapes elsewhere.
20
Thomas, T., M. R. Phillips, A. T. Williams, and R. E. Jenkins. "Short-term beach rotation, wave climate and the North Atlantic Oscillation (NAO)." Progress in Physical Geography: Earth and Environment 35, no. 3 (February 28, 2011): 333–52. http://dx.doi.org/10.1177/0309133310397415.
Full textAbstract:
Beach profile surveys, offshore wave climate and variations in atmospheric conditions have been utilized to assess a short-term beach rotation phenomenon in a headland embayment Tenby, West Wales. Beach rotation, expressed by subaerial volumetric change, was shown by a negative phase relationship between beach extremities (r = —0.67), while cross-correlation at a one-month timelag increased statistical significance (r = 0.84). Due to beach aspect, gale wave heights decreased as wave direction rotated to the south (R2 = 0.4) and west (R 2 = 0.65), while offshore wave direction influenced change at the southern and northern extremities (R2 = 0.52 and 0.34, respectively). Shelter from offshore islands and Giltar Headland contributes via wave diffraction to accretive, erosive and rotational patterns, and these are sensitive to variations around the predominant wave direction (229°). A southerly shift induces north/south sediment movement, as waves diffract around the offshore islands, while a westerly change results in south/north sediment movement (i.e. beach rotation), as diffracted wave domination transfers to the headland. A general gale wave height reduction occurred when the North Atlantic Oscillation (NAO) was weak or in a transitional phase between positive or negative phases (R2 = 0.69 and R2 = 0.72, respectively). Morphological change was also attuned to atmospheric variation where a reversal in beach rotation was influenced by variations in positive and negative NAO/volume correlations and longshore profile location (R2 = 0.54 and 0.69, respectively). The results of this study have wider implications for coastal management; it is suggested that models developed in similar systems elsewhere will form the basis of human intervention or no active intervention strategies.
21
Jawak, Shridhar D., Sagar F. Wankhede, Alvarinho J. Luis, and Keshava Balakrishna. "Impact of Image-Processing Routines on Mapping Glacier Surface Facies from Svalbard and the Himalayas Using Pixel-Based Methods." Remote Sensing 14, no. 6 (March 15, 2022): 1414. http://dx.doi.org/10.3390/rs14061414.
Full textAbstract:
Glacier surface facies are valuable indicators of changes experienced by a glacial system. The interplay of accumulation and ablation facies, followed by intermixing with dust and debris, as well as the local climate, all induce observable and mappable changes on the supraglacial terrain. In the absence or lag of continuous field monitoring, remote sensing observations become vital for maintaining a constant supply of measurable data. However, remote satellite observations suffer from atmospheric effects, resolution disparity, and use of a multitude of mapping methods. Efficient image-processing routines are, hence, necessary to prepare and test the derivable data for mapping applications. The existing literature provides an application-centric view for selection of image processing schemes. This can create confusion, as it is not clear which method of atmospheric correction would be ideal for retrieving facies spectral reflectance, nor are the effects of pansharpening examined on facies. Moreover, with a variety of supervised classifiers and target detection methods now available, it is prudent to test the impact of variations in processing schemes on the resultant thematic classifications. In this context, the current study set its experimental goals. Using very-high-resolution (VHR) WorldView-2 data, we aimed to test the effects of three common atmospheric correction methods, viz. Dark Object Subtraction (DOS), Quick Atmospheric Correction (QUAC), and Fast Line-of-Sight Atmospheric Analysis of Hypercubes (FLAASH); and two pansharpening methods, viz. Gram–Schmidt (GS) and Hyperspherical Color Sharpening (HCS), on thematic classification of facies using 12 supervised classifiers. The conventional classifiers included: Mahalanobis Distance (MHD), Maximum Likelihood (MXL), Minimum Distance to Mean (MD), Spectral Angle Mapper (SAM), and Winner Takes All (WTA). The advanced/target detection classifiers consisted of: Adaptive Coherence Estimator (ACE), Constrained Energy Minimization (CEM), Matched Filtering (MF), Mixture-Tuned Matched Filtering (MTMF), Mixture-Tuned Target-Constrained Interference-Minimized Filter (MTTCIMF), Orthogonal Space Projection (OSP), and Target-Constrained Interference-Minimized Filter (TCIMF). This experiment was performed on glaciers at two test sites, Ny-Ålesund, Svalbard, Norway; and Chandra–Bhaga basin, Himalaya, India. The overall performance suggested that the FLAASH correction delivered realistic reflectance spectra, while DOS delivered the least realistic. Spectra derived from HCS sharpened subsets seemed to match the average reflectance trends, whereas GS reduced the overall reflectance. WTA classification of the DOS subsets achieved the highest overall accuracy (0.81). MTTCIMF classification of the FLAASH subsets yielded the lowest overall accuracy of 0.01. However, FLAASH consistently provided better performance (less variable and generally accurate) than DOS and QUAC, making it the more reliable and hence recommended algorithm. While HCS-pansharpened classification achieved a lower error rate (0.71) in comparison to GS pansharpening (0.76), neither significantly improved accuracy nor efficiency. The Ny-Ålesund glacier facies were best classified using MXL (error rate = 0.49) and WTA classifiers (error rate = 0.53), whereas the Himalayan glacier facies were best classified using MD (error rate = 0.61) and WTA (error rate = 0.45). The final comparative analysis of classifiers based on the total error rate across all atmospheric corrections and pansharpening methods yielded the following reliability order: MXL > WTA > MHD > ACE > MD > CEM = MF > SAM > MTMF = TCIMF > OSP > MTTCIMF. The findings of the current study suggested that for VHR visible near-infrared (VNIR) mapping of facies, FLAASH was the best atmospheric correction, while MXL may deliver reliable thematic classification. Moreover, an extensive account of the varying exertions of each processing scheme is discussed, and could be transferable when compared against other VHR VNIR mapping methods.
22
García-Valero, J. A., J. P. Montávez, J. J. Gómez-Navarro, and P. Jiménez-Guerrero. "Attributing trends in extremely hot days to changes in atmospheric dynamics." Natural Hazards and Earth System Sciences 15, no. 9 (September 30, 2015): 2143–59. http://dx.doi.org/10.5194/nhess-15-2143-2015.
Full textAbstract:
Abstract. This paper presents a method for attributing regional trends in the frequency of extremely hot days (EHDs) to changes in the frequency of the atmospheric patterns that characterize such extraordinary events. The study is applied to mainland Spain and the Balearic Islands for the extended summers of the period 1958–2008, where significant and positive trends in maximum temperature (Tx) have been reported during the second half of the past century. First, the study area was split into eight regions attending to their different temporal variability of the daily Tx series obtained from the Spain02 gridded data set using a clustering procedure. Second, the large-scale atmospheric situations causing EHDs are defined by circulation types (CTs). The obtainment of the CTs differs from the majority of CT classifications proposed in the literature. It is based on regional series and on a previous characterization of the main atmospheric situations obtained using only some days classified as extremes in the different regions. Three different atmospheric fields (SLP, T850, and Z500) from ECMWF reanalysis and analysis data and combinations of them (SLP–T850, SLP–Z500, and T850–Z500) are used to produce six different CT classifications. Subsequently, links between EHD occurrence in the different regions and CT for all days have been established. Finally, a simple model to relate the trends in EHDs for each region to the changes in the CT frequency appearance has been formulated. Most regions present positive and significant trends in the occurrence of EHDs. The CT classifications using two variables perform better. In particular, SLP–T850 is the best for characterizing the atmospheric situations leading to EHD occurrences for most of the regions. Only a small number of CTs have significant trends in their frequency and are associated with high efficiency causing EHD occurrences in most regions simultaneously, especially in the northern and central regions. Attribution results show that changes in circulation can only explain some part of the regional EHD trends. The percentage of the trend attributable to changes in atmospheric dynamics varies from 15 to 50 %, depends on the region and is sensitive to the selected large-scale variables.
23
Jawecki, Bartosz, and Ewa Burszta-Adamiak. "Seasonal variability of basic pollution parameters in atmospheric precipitation in Strzelin." Journal of Water and Land Development 20, no. 1 (March 1, 2014): 31–37. http://dx.doi.org/10.2478/jwld-2014-0001.
Full textAbstract:
Abstract Electrical conductivity and pH are the basic indices of rainfall pollution, constituting the basis for evaluation of the general nature of rainwater. This article presents an analysis of these two parameters in samples of rainfall collected in the years 2008-2010 (in the heating season and outside it) in three measurement sites P1, P2 and P3, located in the city and commune Strzelin (Lower Silesian Voivodeship). Preliminary results show a high variation of pH and electrical conductivity of rainfall occurring in the analysed area. Approximately 30% of the samples were characterised by a pH that allowed to qualify them, according to JANSEN et al. [1988], as normal rainfall. A similar share in all the collected samples represented rainfall of pH < 5.1 that was classified as slightly, considerably and highly acidic. The problem of acid rain occurred in the analysed area mainly during the heating season, when rainfall of pH < 5.1 accounted for a considerable share in all rainfall samples collected in the said period. The electrical conductivity of most samples fell below 60 μS·cm-1, which allowed us to classify them as slightly polluted rainfall (site P2), considerably polluted (site P3) and highly polluted (site P1).
24
Winckler, Johannes, Christian H. Reick, Sebastiaan Luyssaert, Alessandro Cescatti, Paul C. Stoy, Quentin Lejeune, Thomas Raddatz, Andreas Chlond, Marvin Heidkamp, and Julia Pongratz. "Different response of surface temperature and air temperature to deforestation in climate models." Earth System Dynamics 10, no. 3 (July 19, 2019): 473–84. http://dx.doi.org/10.5194/esd-10-473-2019.
Full textAbstract:
Abstract. When quantifying temperature changes induced by deforestation (e.g., cooling in high latitudes, warming in low latitudes), satellite data, in situ observations, and climate models differ concerning the height at which the temperature is typically measured/simulated. In this study the effects of deforestation on surface temperature, near-surface air temperature, and lower atmospheric temperature are compared by analyzing the biogeophysical temperature effects of large-scale deforestation in the Max Planck Institute Earth System Model (MPI-ESM) separately for local effects (which are only apparent at the location of deforestation) and nonlocal effects (which are also apparent elsewhere). While the nonlocal effects (cooling in most regions) influence the temperature of the surface and lowest atmospheric layer equally, the local effects (warming in the tropics but a cooling in the higher latitudes) mainly affect the temperature of the surface. In agreement with observation-based studies, the local effects on surface and near-surface air temperature respond differently in the MPI-ESM, both concerning the magnitude of local temperature changes and the latitude at which the local deforestation effects turn from a cooling to a warming (at 45–55∘ N for surface temperature and around 35∘ N for near-surface air temperature). Subsequently, our single-model results are compared to model data from multiple climate models from the Climate Model Intercomparison Project (CMIP5). This inter-model comparison shows that in the northern midlatitudes, both concerning the summer warming and winter cooling, near-surface air temperature is affected by the local effects only about half as strongly as surface temperature. This study shows that the choice of temperature variable has a considerable effect on the observed and simulated temperature change. Studies about the biogeophysical effects of deforestation must carefully choose which temperature to consider.
25
Zeng, Qiaolin, Jinhua Tao, Liangfu Chen, Hao Zhu, SongYan Zhu, and Yang Wang. "Estimating Ground-Level Particulate Matter in Five Regions of China Using Aerosol Optical Depth." Remote Sensing 12, no. 5 (March 9, 2020): 881. http://dx.doi.org/10.3390/rs12050881.
Full textAbstract:
Aerosol optical depth (AOD) has been widely used to estimate near-surface particulate matter (PM). In this study, ground-measured data from the Campaign on Atmospheric Aerosol Research network of China (CARE-China) and the Aerosol Robotic Network (AERONET) were used to evaluate the accuracy of Visible Infrared Imaging Radiometer Suite (VIIRS) AOD data for different aerosol types. These four aerosol types were from dust, smoke, urban, and uncertain and a fifth “type” was included for unclassified (i.e., total) aerosols. The correlation for dust aerosol was the worst (R2 = 0.15), whereas the correlations for smoke and urban types were better (R2 values of 0.69 and 0.55, respectively). The mixed-effects model was used to estimate the PM2.5 concentrations in Beijing–Tianjin–Hebei (BTH), Sichuan–Chongqing (SC), the Pearl River Delta (PRD), the Yangtze River Delta (YRD), and the Middle Yangtze River (MYR) using the classified aerosol type and unclassified aerosol type methods. The results suggest that the cross validation (CV) of different aerosol types has higher correlation coefficients than that of the unclassified aerosol type. For example, the R2 values for dust, smoke, urban, uncertain, and unclassified aerosol types BTH were 0.76, 0.85, 0.82, 0.82, and 0.78, respectively. Compared with the daily PM2.5 concentrations, the air quality levels estimated using the classified aerosol type method were consistent with ground-measured PM2.5, and the relative error was low (most RE was within ±20%). The classified aerosol type method improved the accuracy of the PM2.5 estimation compared to the unclassified method, although there was an overestimation or underestimation in some regions. The seasonal distribution of PM2.5 was analyzed and the PM2.5 concentrations were high during winter, low during summer, and moderate during spring and autumn. Spatially, the higher PM2.5 concentrations were predominantly distributed in areas of human activity and industrial areas.
26
Westaway, Rob. "Block rotation in western Turkey and elsewhere: 2. Theoretical models." Journal of Geophysical Research 95, B12 (1990): 19885. http://dx.doi.org/10.1029/jb095ib12p19885.
Full text
27
Pallam Raju, D., and R. Sridharan. "High resolution 2-D maps of OI 630.0 nm thermospheric dayglow from equatorial latitudes." Annales Geophysicae 16, no. 8 (August 31, 1998): 997–1006. http://dx.doi.org/10.1007/s00585-998-0997-6.
Full textAbstract:
Abstract. The first-ever high resolution 2-D maps of OI 630.0 nm dayglow obtained from equatorial latitudes clearly reveal the movement as a large-scale feature of the equatorial ionization anomaly (EIA). These also show the presence of wave-like features classified as gravity waves presumably originating at the crest of the EIA, similar to the equatorial electrojet acting as a source of these waves. These results are presented and discussed.Key words. Atmospheric composition and structure (Airglow and aurora) · Ionosphere (Equatorial ionosphere; Instruments and techniques).
28
Muhs, Daniel R., and E. Arthur Bettis. "Geochemical Variations in Peoria Loess of Western Iowa Indicate Paleowinds of Midcontinental North America during Last Glaciation." Quaternary Research 53, no. 1 (January 2000): 49–61. http://dx.doi.org/10.1006/qres.1999.2090.
Full textAbstract:
AbstractPeoria Loess deposited in western Iowa during the last glacial maximum (LGM) shows distinct geochemical and particle-size variations as a function of both depth and distance east of the Missouri River. Geochemical and particle-size data indicate that Peoria Loess in western Iowa probably had two sources: the Missouri River valley, and a source that lay to the west of the Missouri River. Both sources indicate that LGM paleowinds in western Iowa had a strong westerly component, similar to interpretations of previous workers. A compilation of loess studies in Iowa and elsewhere indicates that westerly winds were dominant during loess transport over much of the midcontinent south of the Laurentide ice sheet, which is not in agreement with paleowinds simulated by atmospheric general circulation models (AGCMs). AGCMs consistently generate a glacial anticyclone with easterly or northeasterly winds over the Laurentide ice sheet and the area to the south of it. Loess deposition in the midcontinent during the LGM may be a function of infrequent northwesterly winds that were unrelated to the presence of the glacial anticyclone.
29
Ridgway, Jessica P., Jessica Schmitt, Ellen Almirol, Monique Millington, Erika Harding, and David Pitrak. "Electronic data sharing between public health department and clinical providers improves accuracy of HIV retention data." Open Forum Infectious Diseases 4, suppl_1 (2017): S421—S422. http://dx.doi.org/10.1093/ofid/ofx163.1059.
Full textAbstract:
Abstract Background Retention in care is critical for treatment and prevention of HIV. Many HIV care clinics measure retention rate, but data are often incomplete for patients who are classified as lost to follow-up but may be actually in care elsewhere, moved, or died. The Data to Care (D2C) initiative supports data sharing between health departments and HIV providers to confirm patient care status and facilitate reengagement efforts for out of care HIV patients. Methods The University of Chicago Medicine (UCM) provided an electronic list to the Chicago Department of Public Health (CDPH) of adult HIV-positive patients whose retention status was not certain. Retention in care was defined as at least 2 visits >90 days apart within the prior 12 months. CDPH matched this list of patients with data from the Chicago electronic HIV surveillance database. Matches were based on patient name, including alternative spellings and phonetics, and birth date. CDPH also cross-checked patient names with the CDC’s national enhanced HIV-AIDS Reporting System (eHARS) database. CDPH provided UCM with patient current care status, i.e., patient was in care elsewhere (as verified by lab data), moved out of state, or deceased. Results 780 HIV-positive patients received care in the UCM adult HIV clinic from January 1, 2013 to March 31, 2017. Of these, 360 were retained in care as of March 2017. We shared data with CDPH for 492 patients. Of these, 294 (59.8%) were matched, and 168 (34.1%) had a date of last medical care provided. See Table 1 for patient dispositions, before and after data sharing. 24 (13.4%) of patients believed to be lost to follow up according to UCM records were confirmed either transferred care or deceased according to health department data. Conclusion Data sharing between the health department and HIV providers can improve data accuracy regarding retention in care among people living with HIV. Disclosures J. P. Ridgway, Gilead FOCUS: Grant Investigator, Grant recipient; D. Pitrak, Gilead Sciences FOCUS: Grant Investigator, Grant recipient
30
Bannister, Frank, and Dan Remenyi. "Acts of Faith: Instinct, Value and it Investment Decisions." Journal of Information Technology 15, no. 3 (September 2000): 231–41. http://dx.doi.org/10.1177/026839620001500305.
Full textAbstract:
Although well over 1000 journal articles, conference papers, books, technical notes and theses have been written on the subject of information technology (IT) evaluation, only a relatively small subset of this literature has been concerned with the core issues of what precisely is meant by the term ‘value’ and with the process of making (specifically) IT investment decisions. All too often, the problem and highly complex issue of value is either simplified, ignored or assumed away. Instead the focus of much of the research to date has been on evaluation methodologies and, within this literature, there are different strands of thought which can be classified as partisan, composite and meta approaches to evaluation. Research shows that a small number of partisan techniques are used by most decision makers with a minority using a single technique and a majority using a mixture of such techniques of whom a substantial minority use a formal composite approach. It is argued that, in mapping the set of evaluation methodologies on to what is termed the investment opportunity space, that there is a limit to what can be achieved by formal rational evaluation methods. This limit becomes evident when decision makers fall back on ‘gut feel’ and other non-formal/rigorous ways of making decisions. It is suggested that an understanding of these more complex processes and decision making, in IT as elsewhere, needs tools drawn from philosophy and psychology.
31
Oviatt, Charles G., David B. Madsen, and Dave N. Schmitt. "Late Pleistocene and early Holocene rivers and wetlands in the Bonneville basin of western North America." Quaternary Research 60, no. 2 (September 2003): 200–210. http://dx.doi.org/10.1016/s0033-5894(03)00084-x.
Full textAbstract:
AbstractField investigations at Dugway Proving Ground in western Utah have produced new data on the chronology and human occupation of late Pleistocene and early Holocene lakes, rivers, and wetlands in the Lake Bonneville basin. We have classified paleo-river channels of these ages as “gravel channels” and “sand channels.” Gravel channels are straight to curved, digitate, and have abrupt bulbous ends. They are composed of fine gravel and coarse sand, and are topographically inverted (i.e., they stand higher than the surrounding mudflats). Sand channels are younger and sand filled, with well-developed meander-scroll morphology that is truncated by deflated mudflat surfaces. Gravel channels were formed by a river that originated as overflow from the Sevier basin along the Old River Bed during the late regressive phases of Lake Bonneville (after 12,500 and prior to 11,000 14C yr B.P.). Dated samples from sand channels and associated fluvial overbank and wetland deposits range in age from 11,000 to 8800 14C yr B.P., and are probably related to continued Sevier-basin overflow and to groundwater discharge. Paleoarchaic foragers occupied numerous sites on gravel-channel landforms and adjacent to sand channels in the extensive early Holocene wetland habitats. Reworking of tools and limited toolstone diversity is consistent with theoretical models suggesting Paleoarchaic foragers in the Old River Bed delta were less mobile than elsewhere in the Great Basin.
32
Toolsee, Tesha, and Tarron Lamont. "Long-Term Trends and Interannual Variability of Wind Forcing, Surface Circulation, and Temperature around the Sub-Antarctic Prince Edward Islands." Remote Sensing 14, no. 6 (March 9, 2022): 1318. http://dx.doi.org/10.3390/rs14061318.
Full textAbstract:
In the Southern Ocean, the sub-Antarctic Prince Edward Islands (PEIs) play a significant ecological role by hosting large populations of seasonally breeding marine mammals and seabirds, which are particularly sensitive to changes in the surrounding ocean environment. In order to better understand climate variability at the PEIs, this study used satellite and reanalysis data to examine the interannual variability and longer-term trends of Sea Surface Temperature (SST), wind forcing, and surface circulation. Long-term trends were mostly weak and statistically insignificant, possibly due to the restricted length of the data products. While seasonal fluctuations accounted for a substantial portion (50–70%) of SST variability, the strongest variance in wind speed, wind stress curl (WSC), and currents occurred at intra-annual time scales. At a period of about 1 year, SST and geostrophic current variability suggested some influence of the Southern Annular Mode, but correlations were weak and insignificant. Similarly, correlations with El Niño Southern Oscillation variability were also weak and mostly insignificant, probably due to strong local and regional modification of SST, wind, and current anomalies. Significant interannual and decadal-scale variability in SST, WSC, and geostrophic currents, strongest at periods of 3–4 and 7–8 years, corresponded with the variability of the Antarctic Circumpolar Wave. At decadal time scales, there was a strong inverse relationship between SST and geostrophic currents and between SST and wind speed. Warmer-than-usual SST between 1990–2001 and 2009–2020 was related to weaker currents and wind, while cooler-than-usual periods during 1982–1990 and 2001–2009 were associated with relatively stronger winds and currents. Positioned directly in the path of passing atmospheric low-pressure systems and the Antarctic Circumpolar Current, the PEIs experience substantial local and regional atmospheric and oceanic variability at shorter temporal scales, which likely mutes longer-term variations that have been observed elsewhere in the Southern Ocean.
33
Venyo, Anthony Kodzo-Grey. "Signet Ring Cell Carcinoma of the Prostate Gland: A Review and Update." Cancer Research and Cellular Therapeutics 5, no. 3 (July 26, 2021): 01–14. http://dx.doi.org/10.31579/2640-1053/082.
Full textAbstract:
Signet-ring cell carcinoma of the prostate gland (SRCCP) an uncommon and aggressive malignant tumour of the prostate gland which is characterized by histopathology examination features of compression of the nucleus into the form of a crescent by a large cytoplasmic vacuole. SRCCPs that have so far been reported have been either (a) primary tumours, metastatic tumours with the primary tumour elsewhere with the gastro-intestinal tract being the site of the primary tumour but the primary tumour could originate elsewhere, and additionally some reported SRCCPs have been classified as carcinoma of unknown primary. SRCCP could be a pure tumour or a tumour that is contemporaneously associated with other types of tumour including various variants of adenocarcinoma. SRCCP can manifest in various ways including: Incidental finding following prostatectomy that has been undertaken for a presumed benign prostatic hyperplasia, lower urinary tract symptoms, visible and non-visible haematuria, raised levels of serum PSA but some SRCCPs have been diagnosed with normal / low levels of serum PSA, there may be a history of dyspepsia in cases of metastatic signet-ring cell carcinoma in association with contemporaneous primary signet-ring cell carcinoma of the stomach or there may be a past history of surgical treatment for signet-ring cell carcinoma of the gastrointestinal tract, or bleeding from the gastrointestinal tract in cases of upper gastrointestinal tract and rectal bleeding as well as change in bowel habit for primary tumours of the anorectal region, retention of urine, and rarely a rectal mass in the case of SRCCP with an anorectal primary tumour. In order to exclude a primary signet ring cell carcinoma elsewhere, a detailed past medical history is required as well as radiology imaging including contrast – enhanced computed tomography (CECT) scan and contrast-enhanced magnetic resonance imaging (CEMRI) scan as well as upper gastrointestinal endoscopy and colonoscopy to exclude a primary lesion within the gastrointestinal tract. Diagnosis of SRCCP requires utilization of the histopathology and immunohistochemistry examination features of prostate biopsy, prostatic chips obtained from trans-urethral resection of prostate specimen or radical prostatectomy specimen. SRCCPs upon immunohistochemistry staining studies tend to show tumour that tend to exhibit positive staining for the following tumour markers as follows: PSA – positive staining for PSA has been variable in some studies, AE1/AE3, CAM 5.2, Ki-67 with a mean of 8%, PAS-diastase, Mucicarmine (50%), Alcian blue (60%), Alpha-methyl-acyl coenzyme A racemase (P504S), and Cytokeratin 5/6. SRCCPs also tend to exhibit negative staining for: Bcl2 (rare positive), and CEA (80%). Traditionally the treatment of Primary Signet-Ring Cell Carcinoma of the Prostate Gland has tended to be similar to the treatment of the traditional adenocarcinoma of the prostate gland which does include: hormonal treatment, radiotherapy, and surgery. Nevertheless, considering that primary SRCCPs and metastatic SRCCPs that have been reported in the literature have generally tended to be associated with an aggressive biological behaviour, even though there is no consensus opinion on the treatment of the disease it would be strongly recommended that these tumours that tend to be associated with rapid progress of the disease and poor survival there is an urgent need to treat all these tumours with aggressive surgery including radical prostatectomy plus adjuvant therapies including: radical radiotherapy, combination chemotherapy, selective prostatic angiography and super-selective embolization of the artery feeding the tumour including intra-arterial infusion of chemotherapy agents directly to the tumour, radiofrequency ablation of the tumour as well as irreversible electroporation of the tumour which should form part of a global multicentre study of various treatment options. With regard to metastatic signet-ring cell carcinomas of the prostate gland with a contemporaneous primary tumour elsewhere the primary tumour should also be treated by radical and complete excision of the primary tumour plus radical surgery and aggressive adjuvant therapy. Considering that SRCCPs have tendered not to respond well to available chemotherapy agents, there is need for urologists, oncologists, and pharmacotherapy research workers to identify new chemotherapy medicaments that would more effectively and safely destroy signet-ring cell tumours in order to improve upon the prognosis.
34
Archer van Garderen, E. R. M. "(Re) Considering Cattle Farming in Southern Africa under a Changing Climate." Weather, Climate, and Society 3, no. 4 (October 1, 2011): 249–53. http://dx.doi.org/10.1175/wcas-d-11-00026.1.
Full textAbstract:
Abstract Scientists in southern Africa and elsewhere focusing on climate change and agriculture are increasingly demonstrating how livestock, as a highly climate sensitive sector, may be affected by climate change. The Fourth Assessment Report (AR4) of the Intergovernmental Panel on Climate Change (IPCC) observes, for example, that “Projected increased temperature, combined with reduced precipitation in some regions (e.g., Southern Africa) would lead to increased loss of domestic herbivores during extreme events in drought-prone areas” (Easterling et al.). Response and policy discussions around climate change and agriculture in the Southern African Development Community (SADC) region have, however, thus far tended to focus far more on staple crops. The latest projected future temperatures for southern Africa show a clear increase across most models. Further, temperatures in exceedance of tested livestock comfort thresholds are indicated for the future, particularly for those months of most concern to cattle farmers. Enabling adaptation in the livestock sector should thus be a significant focus of a country’s response to climate change, particularly in countries where the livestock sector is a critical component of the formal and informal economy. Although innovations are often a primary component of livestock adaptation plans under design, it is now recognized that longstanding approaches to the management of livestock may well have valuable lessons for future adaptation. Such approaches include the reintroduction of genetically diverse and resilient breeds, as well as increased support and incentives for those farmers planning and undertaking such approaches.
35
Xu, Feng, Zhaofu Li, Shuyu Zhang, Naitao Huang, Zongyao Quan, Wenmin Zhang, Xiaojun Liu, Xiaosan Jiang, Jianjun Pan, and Alexander V. Prishchepov. "Mapping Winter Wheat with Combinations of Temporally Aggregated Sentinel-2 and Landsat-8 Data in Shandong Province, China." Remote Sensing 12, no. 12 (June 26, 2020): 2065. http://dx.doi.org/10.3390/rs12122065.
Full textAbstract:
Winter wheat is one of the major cereal crops in China. The spatial distribution of winter wheat planting areas is closely related to food security; however, mapping winter wheat with time-series finer spatial resolution satellite images across large areas is challenging. This paper explores the potential of combining temporally aggregated Landsat-8 OLI and Sentinel-2 MSI data available via the Google Earth Engine (GEE) platform for mapping winter wheat in Shandong Province, China. First, six phenological median composites of Landsat-8 OLI and Sentinel-2 MSI reflectance measures were generated by a temporal aggregation technique according to the winter wheat phenological calendar, which covered seedling, tillering, over-wintering, reviving, jointing-heading and maturing phases, respectively. Then, Random Forest (RF) classifier was used to classify multi-temporal composites but also mono-temporal winter wheat development phases and mono-sensor data. The results showed that winter wheat could be classified with an overall accuracy of 93.4% and F1 measure (the harmonic mean of producer’s and user’s accuracy) of 0.97 with temporally aggregated Landsat-8 and Sentinel-2 data were combined. As our results also revealed, it was always good to classify multi-temporal images compared to mono-temporal imagery (the overall accuracy dropped from 93.4% to as low as 76.4%). It was also good to classify Landsat-8 OLI and Sentinel-2 MSI imagery combined instead of classifying them individually. The analysis showed among the mono-temporal winter wheat development phases that the maturing phase’s and reviving phase’s data were more important than the data for other mono-temporal winter wheat development phases. In sum, this study confirmed the importance of using temporally aggregated Landsat-8 OLI and Sentinel-2 MSI data combined and identified key winter wheat development phases for accurate winter wheat classification. These results can be useful to benefit on freely available optical satellite data (Landsat-8 OLI and Sentinel-2 MSI) and prioritize key winter wheat development phases for accurate mapping winter wheat planting areas across China and elsewhere.
36
Voudouri, Kalliopi Artemis, Konstantinos Michailidis, Nikolaos Siomos, Anthi Chatzopoulou, Georgios Kouvarakis, Nikolaos Mihalopoulos, Paraskevi Tzoumaka, Apostolos Kelessis, and Dimitrios Balis. "Evaluation of Aerosol Typing with Combination of Remote Sensing Techniques with In Situ Data during the PANACEA Campaigns in Thessaloniki Station, Greece." Remote Sensing 14, no. 20 (October 11, 2022): 5076. http://dx.doi.org/10.3390/rs14205076.
Full textAbstract:
Two measurement campaigns were conducted at Thessaloniki, an urban station, (40.5°N, 22.9°E; 60 m) in the frame of the PANhellenic infrastructure for Atmospheric Composition and climatEchAnge (PANACEA) project. The first one covers the period from July to August 2019 and the second one from January to February An overview of the aerosol optical properties (columnar and height resolved), acquired with the remote sensing infrastructure of the Laboratory of Atmospheric Physics (LAP) of the Aristotle University of Thessaloniki (AUTH), as well as the additional instrumentation that participated during the PANACEA campaigns is presented. The majority of the detected layers (16 out of 40, ranged between 0.8 and 4.5 km) are classified as biomass burning aerosols, attributed to either city sources or long range transport. Concerning the other aerosol types, the Clean Continental cluster has an occurrence ratio of 23%, while dust layers and mixtures with urban particles transported to Thessaloniki are also identified. Our findings are discussed along with the surface information, i.e., the particulate matter (PM2.5 and PM10) concentrations and the black carbon (BC) concentration, separated into fossil fuel (BCff) and biomass/wood burning (BCwb) fractions. This is the first time that collocated in situ and remote sensing instruments are deployed in Thessaloniki in order to assess the presence of aerosols and the predominant aerosol type both in situ and at elevated heights. Overall, our study showed that the BCwb contribution to the BC values in Thessaloniki is quite low (11%), whilst the majority of the biomass burning layers identified with the lidar system, are also linked with enhanced BC contribution and high Fine Mode Fraction values.
37
Pastor, Francisco, Jose Antonio Valiente, and Samiro Khodayar. "A Warming Mediterranean: 38 Years of Increasing Sea Surface Temperature." Remote Sensing 12, no. 17 (August 20, 2020): 2687. http://dx.doi.org/10.3390/rs12172687.
Full textAbstract:
The Mediterranean basin has been classified as a hot-spot for climate change. The Mediterranean Sea plays a fundamental regulatory role in the regional climate. We have analyzed the largest available and complete time series (1982–2019) of blended sea surface temperature (SST) data to study its seasonal cycle and look for a possible warming trend in the basin. From the analysis of the Mediterranean mean SST time series, a new temporal seasonal division is derived that differs from the one used in atmospheric climatology. Then, the SST time series were decomposed into their seasonal and trend components, and a consistent warming trend of 0.035 °C/year was obtained. The nature of this trend has been investigated, indicating a higher warming trend for both maximum and high/summer SST values than for the winter/colder ones. This reinforces the consistency of the SST increase since it is not only based on the presence of extreme values, but on a homogeneous basin global increase of high SST records as well. Although warming is found throughout the Mediterranean basin, the spatial variability found leads to the division of the basin into three distinct subareas regarding warming.
38
Martínez-Alvarado, O., L. Montabone, S. R. Lewis, I. M. Moroz, and P. L. Read. "Transient teleconnection event at the onset of a planet-encircling dust storm on Mars." Annales Geophysicae 27, no. 9 (September 30, 2009): 3663–76. http://dx.doi.org/10.5194/angeo-27-3663-2009.
Full textAbstract:
Abstract. We use proper orthogonal decomposition (POD) to study a transient teleconnection event at the onset of the 2001 planet-encircling dust storm on Mars, in terms of empirical orthogonal functions (EOFs). There are several differences between this and previous studies of atmospheric events using EOFs. First, instead of using a single variable such as surface pressure or geopotential height on a given pressure surface, we use a dataset describing the evolution in time of global and fully three-dimensional atmospheric fields such as horizontal velocity and temperature. These fields are produced by assimilating Thermal Emission Spectrometer observations from NASA's Mars Global Surveyor spacecraft into a Mars general circulation model. We use total atmospheric energy (TE) as a physically meaningful quantity which weights the state variables. Second, instead of adopting the EOFs to define teleconnection patterns as planetary-scale correlations that explain a large portion of long time-scale variability, we use EOFs to understand transient processes due to localised heating perturbations that have implications for the atmospheric circulation over distant regions. The localised perturbation is given by anomalous heating due to the enhanced presence of dust around the northern edge of the Hellas Planitia basin on Mars. We show that the localised disturbance is seemingly restricted to a small number (a few tens) of EOFs. These can be classified as low-order, transitional, or high-order EOFs according to the TE amount they explain throughout the event. Despite the global character of the EOFs, they show the capability of accounting for the localised effects of the perturbation via the presence of specific centres of action. We finally discuss possible applications for the study of terrestrial phenomena with similar characteristics.
39
Alawad, Kamal A., Abdullah M. Al-Subhi, Mohammed A. Alsaafani, and Turki M. Alraddadi. "Atmospheric Forcing of the High and Low Extremes in the Sea Surface Temperature over the Red Sea and Associated Chlorophyll-a Concentration." Remote Sensing 12, no. 14 (July 11, 2020): 2227. http://dx.doi.org/10.3390/rs12142227.
Full textAbstract:
Taking advantage of 37-year-long (1982–2018) of high-quality satellite datasets, we examined the role of direct atmospheric forcing on the high and low sea surface temperature (SST) extremes over the Red Sea (RS). Considering the importance of SST in regulating ocean physics and biology, the associated impacts on chlorophyll (Chl-a) concentration were also explored, since a small change in SST can cause a significant impact in the ocean. After describing the climate features, we classified the top 5% of SST values (≥31.5 °C) as extreme high events (EHEs) during the boreal summer period and the lowest SST values (≤22.8 °C) as extreme low events (ELEs) during the boreal winter period. The spatiotemporal analysis showed that the EHEs (ELEs) were observed over the southern (northern) basin, with a significant warming trend of 0.027 (0.021) °C year−1, respectively. The EHEs were observed when there was widespread less than average sea level pressure (SLP) over southern Europe, northeast Africa, and Middle East, including in the RS, leading to the cold wind stress from Europe being relatively less than usual and the intrusion of stronger than usual relatively warm air mass from central Sudan throughout the Tokar Gap. Conversely, EHEs were observed when above average SLP prevailed over southern Europe and the Mediterranean Sea as a result of the Azores high and westward extension of the Siberian anticyclone, which led to above average transfer of cold and dry wind stress from higher latitudes. At the same time, notably less wind stress due to southerlies that transfer warm and humid air masses northward was observed. Furthermore, physical and biological responses related to extreme stress showed distinct ocean patterns associated with each event. It was found that the Chl-a concentration anomalies over the northern basin caused by vertical nutrient transport through deep upwelling processes are the manifestation of the superimposition of ELEs. The situation was the opposite for EHEs due to the stably stratified ocean boundary layer, which is a well-known consequence of global warming.
40
Singh, Neelu, Vartika Singh, and Chikkamadaiah Krishnaiah. "The study of atmospherically deposited Spheroidal Carbonaceous Particles (SCP) from the Kongsfjorden, Svalbard." Czech Polar Reports 7, no. 2 (June 1, 2017): 206–15. http://dx.doi.org/10.5817/cpr2017-2-20.
Full textAbstract:
The surface sediment samples of Kongsfjorden were analyzed for the Spheroidal Carbonaceous Particles (SCP) in an attempt to document the SCP in the environment other than previously studied inland lakes and snow and also to understand the probable source of industrial atmospheric pollution. The SCP are derived from the combustion of fossil fuels at high temperatures and are not produced naturally. They are chemically inert in both sediment and water and thus provide the indestructible record of atmospherically deposited pollutants in remote areas and anthropogenic impact on pristine environments. The SCP were recovered from different locations of the fjord and were classified according to their size range (small particles, 5-10 µm – large particles, 20-50 µm). The characterization of the spherical carbonaceous particles (shape, size, morphology, color etc.) was done under the light microscope. The detailed morphological features and chemical composition of SCP were studied using Scanning Electron Microscope equipped with Energy Dispersive X-Ray (SEM-EDX). The result shows that in term of a source of pollution in the area, long-range transportation is the major source of pollution but local sources cannot be ignored. This is a first attempt to study the SCP from the Kongsfjorden.
41
Poix, Christophe, Guy Febvre, Anne Fouilloux, Howard Larsen, and Jean-Francois Gayet. "The retrieval of cloud microphysical properties using satellite measurements and an in situ database." Annales Geophysicae 14, no. 1 (January 31, 1996): 98–106. http://dx.doi.org/10.1007/s00585-996-0098-3.
Full textAbstract:
Abstract. By combining AVHRR data from the NOAA satellites with information from a database of in situ measurements, large-scale maps can be generated of the microphysical parameters most immediately significant for the modelling of global circulation and climate. From the satellite data, the clouds can be classified into cumuliform, stratiform and cirrus classes and then into further sub-classes by cloud top temperature. At the same time a database of in situ measurements made by research aircraft is classified into the same sub-classes and a statistical analysis is used to derive relationships between the sub-classes and the cloud microphysical properties. These two analyses are then linked to give estimates of the microphysical properties of the satellite observed clouds. Examples are given of the application of this technique to derive maps of the probability of occurrence of precipitating clouds and of precipitating water content derived from a case study within the International Cirrus Experiment (ICE) held in 1989 over the North Sea.
42
Chmara, Rafał, Eugeniusz Pronin, and Józef Szmeja. "Functional macrophyte trait variation as a response to the source of inorganic carbon acquisition." PeerJ 9 (December 1, 2021): e12584. http://dx.doi.org/10.7717/peerj.12584.
Full textAbstract:
Background This study aims to compare variation in a range of aquatic macrophyte species leaf traits into three carbon acquisition groups: HCO3−, free CO2 and atmospheric CO2. Methods The leaf functional traits were measured for 30 species from 30 softwater lakes. Macrophyte species were classified into (1) free CO2, (2) atmospheric CO2 and (3) bicarbonate HCO3− groups. In each lake we collected water samples and measured eight environmental variables: depth, Secchi depth, photosynthetically active radiation (PAR), pH of water, conductivity, calcium concentration, total nitrogen and total phosphorus. In this study we applied the RLQ analysis to investigate the relationships between species functional traits (Q) and their relationship with environmental variables (R) constrained by species abundance (L). Results The results showed that: (1) Aquatic macrophytes exhibited high leaf trait variations as a response to different inorganic carbon acquisition; (2) Traits of leaves refer to the acquisition of carbon for photosynthesis and serve to maximise this process; (3) In the wide softwater habitat, macrophyte species exhibited an extreme range of leaf economic spectrum (leaf area, leaf dry weight and specific leaf area) and wide range of shape trait expressed as circularity; (4) Macrophyte leaf traits are the result of adaptation to carbon acquisition in ambient environment.
43
Das, Karumampoyil Sakthidas Anoop, Dhanya Radhamany, and Freerk Molleman. "Community Structure in an Isolated Tropical Forest Biome: One Year of Fruit-Feeding Butterfly Trapping in Four Habitats in the Western Ghats, India." Diversity 15, no. 1 (December 28, 2022): 36. http://dx.doi.org/10.3390/d15010036.
Full textAbstract:
Insect communities in tropical forests tend to be structured vertically and with respect to tree fall gaps and edges. Furthermore, insect communities vary over time. Insight into such habitat specificity and temporal variation is needed to design and interpret biodiversity surveys and to compare conservation value among habitats. Some aspects of tropical insect community structure, such as the proportion of canopy specialists and temporal variation, vary among biogeographical regions and climatic zones. To date, few regions have been sampled systematically, so generalization remains difficult. We compared fruit-feeding butterfly communities among understory, canopy, natural treefalls, and forest edge, in a tropical forest of the Western Ghats, a strip of rainforest that is isolated from Sundaland, the large rainforest block of South-East Asia. During a yearlong study, we captured 3018 individuals belonging to 32 species and representing 14 genera. While some butterflies were captured in the canopy, no species was significantly more abundant in the canopy than in the understory. This observation was contrary to studies elsewhere in the tropics where 14–55% of the species could be classified as canopy specialists. Even though the largest number of species was captured at forest edges, species diversity was highest in the gaps. The communities at the forest edge differed importantly from those in treefall gaps: at the forest edge, we caught grassland species in addition to the forest species. Larger treefall gaps had higher butterfly abundance than smaller gaps. Both abundance and diversity peaked during the late monsoon season, and all common species in our sample also peaked during this period. The spatiotemporal community structure appears to depend on biogeography (less vertical stratification further from large forest blocks) and climate (more synchrony among species in seasonal abundance when there is a more severe dry season).
44
Piotrowicz, Katarzyna, and Joanna Szlagor. "The Link Between from Day to Day Change of Weather Types and Synoptic Situations in Kraków During the Period 1961–2010." Quaestiones Geographicae 32, no. 3 (September 1, 2013): 69–84. http://dx.doi.org/10.2478/quageo-2013-0023.
Full textAbstract:
Abstract This paper analyses day-to-day changes of weather types and links these with synoptic situations, i.e. circulation types, air masses and weather fronts. The weather types were classified according to Woś (1999), while a calendar proposed by Niedźwiedź (2013) was used for synoptic situations. Weather records from Kraków were used covering the period 1961-2010. The frequency of all combinations of day-to-day weather type changes was calculated, identified using specific values of air temperature, cloudiness and precipitation. The analysis of the succession and frequency of the day-to-day changes was linked with the synoptic situations accompanying the change. It was found that the thermal weather types were relatively very stable and remained unchanged on the following day in 61.3% of cases, and that the synoptic situation also remained similar. Weather subtypes, identified with just cloudiness and precipitation, but not temperature, displayed much more day-to-day change in terms of frequency and scale. Synoptically it was the air mass change and/or the occurrence of atmospheric fronts, which tended to cause day-to-day weather type changes, while the impact of circulation was not always clear. Particular attention was devoted to sudden weather type changes caused primarily by dramatic air temperature fluctuations.
45
Guo, Xiaobo, Libin Zhao, Wei Han, Longfei Zhou, Zhilong Huang, Xiongwei Sun, Xuejun Yang, Tonghui Zhang, and Chenglin Zhang. "Geochemistry of Formation Water and Implications for Ultradeep Tight Sandstone of DK Gas Field in Kuqa Depression." Geofluids 2022 (November 18, 2022): 1–14. http://dx.doi.org/10.1155/2022/6514733.
Full textAbstract:
Formation water is produced during gas well production, which can seriously affect gas well productivity, especially in deep and ultradeep tight sandstone gas reservoirs. In this paper, we have studied the formation water production and geochemical properties of the ultradeep tight sandstone gas reservoir in the Cretaceous Bashijiqike Formation of the DK gas field in the Kuqa Depression. The results indicate that the formation water can be classified as condensate water, gas-water transition zone water, mixed water, and isolated formation water, all of which are acidic and of CaCl2 type, with increasing salinity or chloride ion content. Sodium/chloride ratio (ρNa+/ρCl-), metamorphic coefficient (ρ(Cl--Na+)/ρ(Mg2+)), desulfurization coefficient ( 100 × ρ S O 4 2 − / ρ C l − ), and trace elements concentration parameters show that the formation water was formed in a closed and reductive environment and experienced strong water-rock interaction. The formation water may have been influenced by early seawater, but it is not significant and is more likely to have been influenced by water seepage from the overlying gypsum strata. The Sr, H, and O isotopes reveal that the different types of formation water have good homology and are not affected by atmospheric precipitation, which is propitious to the preservation of natural gas.
46
Price, Owen F., Bronwyn Horsey, and Ningbo Jiang. "Local and regional smoke impacts from prescribed fires." Natural Hazards and Earth System Sciences 16, no. 10 (October 14, 2016): 2247–57. http://dx.doi.org/10.5194/nhess-16-2247-2016.
Full textAbstract:
Abstract. Smoke from wildfires poses a significant threat to affected communities. Prescribed burning is conducted to reduce the extent and potential damage of wildfires, but produces its own smoke threat. Planners of prescribed fires model the likely dispersion of smoke to help manage the impacts on local communities. Significant uncertainty remains about the actual smoke impact from prescribed fires, especially near the fire, and the accuracy of smoke dispersal models. To address this uncertainty, a detailed study of smoke dispersal was conducted for one small (52 ha) and one large (700 ha) prescribed fire near Appin in New South Wales, Australia, through the use of stationary and handheld pollution monitors, visual observations and rain radar data, and by comparing observations to predictions from an atmospheric dispersion model. The 52 ha fire produced a smoke plume about 800 m high and 9 km long. Particle concentrations (PM2.5) reached very high peak values (> 400 µg m−3) and high 24 h average values (> 100 µg m−3) at several locations next to or within ∼ 500 m downwind from the fire, but low levels elsewhere. The 700 ha fire produced a much larger plume, peaking at ∼ 2000 m altitude and affecting downwind areas up to 14 km away. Both peak and 24 h average PM2.5 values near the fire were lower than for the 52 ha fire, but this may be because the monitoring locations were further away from the fire. Some lofted smoke spread north against the ground-level wind direction. Smoke from this fire collapsed to the ground during the night at different times in different locations. Although it is hard to attribute particle concentrations definitively to smoke, it seems that the collapsed plume affected a huge area including the towns of Wollongong, Bargo, Oakdale, Camden and Campbelltown (∼ 1200 km2). PM2.5 concentrations up to 169 µg m−3 were recorded on the morning following the fire. The atmospheric dispersion model accurately predicted the general behaviour of both plumes in the early phases of the fires, but was poor at predicting fine-scale variation in particulate concentrations (e.g. places 500 m from the fire). The correlation between predicted and observed varied between 0 and 0.87 depending on location. The model also completely failed to predict the night-time collapse of the plume from the 700 ha fire. This study provides a preliminary insight into the potential for large impacts from prescribed fire smoke to NSW communities and the need for increased accuracy in smoke dispersion modelling. More research is needed to better understand when and why such impacts might occur and provide better predictions of pollution risk.
47
Dorman, L. I. "Prediction of galactic cosmic ray intensity variation for a few (up to 10-12) years ahead on the basis of convection-diffusion and drift model." Annales Geophysicae 23, no. 9 (November 22, 2005): 3003–7. http://dx.doi.org/10.5194/angeo-23-3003-2005.
Full textAbstract:
Abstract. We determine the dimension of the Heliosphere (modulation region), radial diffusion coefficient and other parameters of convection-diffusion and drift mechanisms of cosmic ray (CR) long-term variation, depending on particle energy, the level of solar activity (SA) and general solar magnetic field. This important information we obtain on the basis of CR and SA data in the past, taking into account the theory of convection-diffusion and drift global modulation of galactic CR in the Heliosphere. By using these results and the predictions which are regularly published elsewhere of expected SA variation in the near future and prediction of next future SA cycle, we may make a prediction of the expected in the near future long-term cosmic ray intensity variation. We show that by this method we may make a prediction of the expected in the near future (up to 10-12 years, and may be more, in dependence for what period can be made definite prediction of SA) galactic cosmic ray intensity variation in the interplanetary space on different distances from the Sun, in the Earth's magnetosphere, and in the atmosphere at different altitudes and latitudes.
48
Wu, Ying, Bo Qian, Yansong Bao, George P. Petropoulos, Xulin Liu, and Lin Li. "Microwave Land Emissivity Calculations over the Qinghai-Tibetan Plateau Using FY-3B/MWRI Measurements." Remote Sensing 11, no. 19 (September 20, 2019): 2206. http://dx.doi.org/10.3390/rs11192206.
Full textAbstract:
The Qinghai-Tibetan plateau plays an important role in climate change with its unique characteristics, and the surface emissivity is an important parameter to describe the surface characteristics. It is also very important for the accurate retrieval of surface and atmospheric parameters. Different types of surface features have their own radiation characteristics due to their differences in structure, water content and roughness. In this study, the microwave land surface emissivity (10.65, 18.7, 23.8, 36.5 and 89 GHz) of the Qinghai-Tibetan Plateau was calculated using the simplified microwave radiation transmission equation under clear atmospheric conditions based on Level 1 brightness temperatures from the Microwave Radiation Imager onboard the FY-3B meteorological satellite (FY-3B/MWRI) and the National Centers for Environmental Prediction Final (NCEP-FNL) Global Operational Analysis dataset. Furthermore, according to the IGBP (International Geosphere-Biosphere Program) classified data, the spectrum and spatial distribution characteristics of microwave surface emittance in Qinghai-Tibetan plateau were further analyzed. The results show that almost all 16 types of emissivity from IGBP at dual-polarization (vertical and horizontal) increase with the increase of frequency. The spatial distribution of the retrieving results is in line with the changes of surface cover types on the Qinghai-Tibetan plateau, showing the distribution characteristics of large polarization difference of surface emissivity in the northwest and small polarization difference in the southeast, and diverse vegetation can be clearly seen in the retrieving results. In addition, the emissivity is closely related to the type of land surface. Since the emissivity of vegetation is higher than that of bare soil, the contribution of bare soil increases and the surface emissivity decreases as the density of vegetation decreases. Finally, the source of retrieval error was analyzed. The errors in calculating the surface emissivity might mainly come from spatiotemporal collocation of reanalysis data with satellite measurements, the quality of these auxiliary datasets and cloud and precipitation pixel discrimination scheme. Further quantitative analysis of these errors is required, and even standard procedures may need to be improved as well to improve the accuracy of the calculation.
49
Marchetti, Dedalo, Kaiguang Zhu, Hanshuo Zhang, Zeren Zhima, Rui Yan, Xuhui Shen, Wenqi Chen, et al. "Clues of Lithosphere, Atmosphere and Ionosphere Variations Possibly Related to the Preparation of La Palma 19 September 2021 Volcano Eruption." Remote Sensing 14, no. 19 (October 8, 2022): 5001. http://dx.doi.org/10.3390/rs14195001.
Full textAbstract:
On 19 September 2021, La Palma Cumbre Vieja Volcano started an eruption classified as Volcanic Explosive Index (VEI) 3. In this study, at least the six months prior to such an event have been investigated to search for possible lithosphere–atmosphere–ionosphere bottom-up interactions. The lithosphere has been analysed in terms of seismicity getting advantages from the high-density local seismic network. Possible atmospheric alterations related to the volcano emissions or release of gases due to the uplift of the magmatic chamber have been searched in SO2, aerosol, dimethyl sulphide, and CO. The magnetic field on Earth’s surface has been studied by ground geomagnetic observatories. The status of the ionosphere has been investigated with two satellite missions: China Seismo Electromagnetic Satellite (CSES) and European Space Agency Swarm constellation, with Total Electron Content (TEC) retrieved from global maps. We identified a temporal migration of the seismicity from November 2020 at a depth of 40 km that seems associable to magma migration, firstly to a deep chamber at about 15 km depth and in the last 10 days in a shallow magma chamber at less than 5 km depth. The atmospheric composition, ground geomagnetic field, and ionosphere showed anomalies from more than three months before the eruption, suggesting a possible influence from the bottom geo-layers to the upper ones. CSES-01 detected an increase of electron density, confirmed by TEC data, and alterations of vertical magnetic field on ground Guimar observatory that are temporal compatible with some volcanic low seismic activity (very likely due to the magma uplift), suggesting an eventual electromagnetic disturbance from the lithosphere to the ionosphere. A final increase of carbon monoxide 1.5 months before the eruption with unusually high values of TEC suggests the last uplifting of the magma before the eruption, confirmed by a very high shallow seismicity that preceded the eruption by ten days. This work underlines the importance of integrating several observation platforms from ground and overall space to understand geophysics better, and, in particular, the natural hazard affecting our planet.
50
Kalitka, L. S. "Automated detection of agricultural land overgrowing using WorldView and Sentinel-2." Geodesy and Cartography 978, no. 12 (January 20, 2022): 46–52. http://dx.doi.org/10.22389/0016-7126-2021-978-12-46-52.
Full textAbstract:
The author considers the possibility of areas overgrowing automated determination in agricultural territory to reduce the time required to perform tasks of identifying disturbed lands and decrease the human factor influencing the result. The methodology is based on a system of converting the initial remote sensing data into a segmented image. The purpose is to achieve the highest reliability of percentage at further uncontrolled classification. The initial data is that of space survey with high and medium spatial resolution, geometric and atmospheric correction and vector boundaries of agricultural fields. The author applies the watershed method to the original images to increase the reliability of the final result. The Sobel operator is used as preprocessing method to create a gradient image. Further joining of adjacent homogeneous segments together is carried out using the Full Lambda Schedule method. The segmented image is classified through the k-means clustering technique. Materials from WorldView-3 and Sentinel-2 satellites agricultural territories in the Republic of Kalmykia and Kaluga oblast were used. The classification result is analyzed and on its basis an overgrowth vector mask of agricultural fields is created.