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81.
ABSTRACTSocial media are increasingly recognized as a useful data source for understanding social response to hazard events in real time and in post-event analysis. This article establishes social media–enhanced decision support systems (SME-DSS) as a synergistic integration of social media and decision support systems (DSSs) to provide structured access to native, near real-time data from a large and diverse population to assess social response to social, environmental, and technological risk and hazard events. We introduce a prototype SME-DSS entitled socio-environmental data explorer (SEDE) to explore the opportunities and challenges of leveraging social media for decision support. We use a winter storm during 25–28 January 2015 that accumulated record amounts of snow along the East Coast of the United States as a case study to evaluate SEDE in helping assess social response to environmental risk and hazard events as well as evaluate social media as a theoretical component within the social amplification of risk framework (SARF) that serves as a theoretical foundation for SME-DSS. 相似文献
82.
Bandar I. Ghassal Haytham El Atfy Victoria Sachse Ralf Littke 《Arabian Journal of Geosciences》2016,9(20):744
Organic geochemical characterization of cutting samples from the Abu Hammad-1 and Matariya-1 wells elucidates the depositional environment and source rock potential of the Jurassic and Lower Cretaceous successions and the Middle Miocene to Pleistocene section in the southern and eastern Nile Delta Basin. The burial and thermal histories of the Mesozoic and Miocene sections were modeled using 1D basin modeling based on input data from the two wells. This study reveals fair to good gas-prone source rocks within the Upper Jurassic and Lower Cretaceous sections with total organic carbon (TOC) averaging 2.7% and hydrogen index (HI) up to 130 mg HC/g TOC. The pristane/n-C17 versus phytane/n-C18 correlation suggests mixed marine and terrestrial organic matter with predominant marine input. Burial and thermal history modeling reveals low thermal maturity due to low heat flow and thin overburden. These source rocks can generate gas in the western and northern parts of the basin where they are situated at deeper settings. In contrast, the thick Middle Miocene shows fair source rock quality (TOC averaging at 1.4%; HI maximizing at 183 mg HC/g TOC). The quality decreases towards the younger section where terrestrial organic matter is abundant. This section is similar to previously studied intervals in the eastern Nile Delta Basin but differs from equivalents in the central parts where the quality is better. Based on 1D modeling, the thick Middle Miocene source rocks just reached the oil generation stage, but microbial gas, however, is possible. 相似文献
83.
Des Gasper Ana Victoria Portocarrero Asuncion Lera St.Clair 《Global Environmental Change》2013,23(1):28-39
The Human Development Report 2007/8 (HDR) and the World Development Report 2010 (WDR) are both devoted to the connections between climate change and development. The reports provide very different perspectives on where the key challenges reside. Their policy proposals are also different, but much less so. Using a combination of frame and content analysis complemented with attention to how these institutions and their knowledge production processes operate, the paper develops a structured comparison of the problem-framing and solution-framing in the Overviews of the two reports. It compares the reports’ conceptions of development; their normative content and the roles given to human rights; the pathways and solutions the agencies defend, and how protective they are of the poor; the status given to proposed market solutions; what types of information and expert perspective are prioritized and why, and which issues are neglected. Following its stress on human rights and ethical principles, the HDR does not unsettle the market driven solutions to climate change that dominate the global policy arena. Different policy instruments and a fuller institutionalization of its human rights concerns is required, in organizations, processes, methodologies and knowledge networks that could move the ideas forward and continually press for their use. This may require a different model of report preparation. 相似文献
84.
Victoria J. Hill Richard C. Zimmerman 《Deep Sea Research Part I: Oceanographic Research Papers》2010,57(10):1243-1254
The Arctic Ocean, including its regional shelf seas, is assumed to play an important role in the global carbon cycle. However, the true magnitude of annual production is unknown, as in situ data are sparse in time and space. Remote sensing technology has the potential to provide large scale estimates of phytoplankton biomass at much higher frequency and spatial coverage than shipboard observations in this remote region. Subsurface peaks in both biomass and primary production (PP), which are the characteristics of the Arctic, are shown to limit the reliability of ocean color based integrated PP (IPP) models in the Chukchi Sea. Here we report that the retrievals of IPP from remotely sensed ocean color data were accurate only when limited to 1.2 optical depths, which severely constrains the utility of ocean color remote sensing for the assessment of Arctic Ocean dynamics.Active sensors such as LIDAR, can, in combination with passive ocean color, dramatically improve our ability to estimate IPP for the Arctic. IPP retrievals were improved to within a factor of 2–3 of the measured values, when the vertical distribution of Chl a was determined to a resolution of 1 m using modeled LIDAR retrievals of the beam attenuation coefficient. This was far better than models using only passive ocean color. The instrument specifications of the current NASA spaceborne LIDAR (CALIOP) allow for the retrieval of Kd at a depth resolution of 23 m. Even with this constraint, however, the accuracy of the modeled IPP was improved over passive ocean color retrievals to approximately a factor of 3. The Arctic is a perfect location to merge ocean color and LIDAR measurements as the polar orbit of CALIOP provides complete grid coverage of the area every 8 days, crossing the horizontal gradients in Chl a already known to exist from passive ocean color observations. 相似文献
85.
James D. Scourse Anna I. Haapaniemi Elena Colmenero-Hidalgo Victoria L. Peck Ian R. Hall William E.N. Austin Paul C. Knutz Rainer Zahn 《Quaternary Science Reviews》2009,28(27-28):3066-3084
The evolution and dynamics of the last British–Irish Ice Sheet (BIIS) have hitherto largely been reconstructed from onshore and shallow marine glacial geological and geomorphological data. This reconstruction has been problematic because these sequences and data are spatially and temporally incomplete and fragmentary. In order to enhance BIIS reconstruction, we present a compilation of new and previously published ice-rafted detritus (IRD) flux and concentration data from high-resolution sediment cores recovered from the NE Atlantic deep-sea continental slope adjacent to the last BIIS. These cores are situated adjacent to the full latitudinal extent of the last BIIS and cover Marine Isotope Stages (MIS) 2 and 3. Age models are based on radiocarbon dating and graphical tuning of abundances of the polar planktonic foraminifera Neogloboquadrina pachyderma sinistral (% Nps) to the Greenland GISP2 ice core record. Multiple IRD fingerprinting techniques indicate that, at the selected locations, most IRD are sourced from adjacent BIIS ice streams except in the centre of Heinrich (H) layers in which IRD shows a prominent Laurentide Ice Sheet provenance. IRD flux data are interpreted with reference to a conceptual model explaining the relations between flux, North Atlantic hydrography and ice dynamics. Both positive and rapid negative mass balance can cause increases, and prominent peaks, in IRD flux. First-order interpretation of the IRD record indicates the timing of the presence of the BIIS with an actively calving marine margin. The records show a coherent latitudinal, but partly phased, signal during MIS 3 and 2. Published data indicate that the last BIIS initiated during the MIS 5/4 cooling transition; renewed growth just before H5 (46 ka) was succeeded by very strong millennial-scale variability apparently corresponding with Dansgaard–Oeschger (DO) cycles closely coupled to millennial-scale climate variability in the North Atlantic region involving latitudinal migration of the North Atlantic Polar Front. This indicates that the previously defined “precursor events” are not uniquely associated with H events but are part of the millennial-scale variability. Major growth of the ice sheet occurred after 29 ka with the Barra Ice Stream attaining a shelf-edge position and generating turbiditic flows on the Barra–Donegal Fan at ~27 ka. The ice sheet reached its maximum extent at H2 (24 ka), earlier than interpreted in previous studies. Rapid retreat, initially characterised by peak IRD flux, during Greenland Interstadial 2 (23 ka) was followed by readvance between 22 and 16 ka. Readvance during H1 was only characterised by BIIS ice streams draining central dome(s) of the ice sheet, and was followed by rapid deglaciation and ice exhaustion. The evidence for a calving margin and IRD supply from the BIIS during Greenland Stadial 1 (Younger Dryas event) is equivocal. The timing of the initiation, maximum extent, deglacial and readvance phases of the BIIS interpreted from the IRD flux record is strongly supported by recent independent data from both the Irish Sea and North Sea sectors of the ice sheet. 相似文献
86.
Joanna Petrasek MacDonald Sherilee L. Harper Ashlee Cunsolo Willox Victoria L. Edge 《Global Environmental Change》2013,23(1):360-371
Globally, youth voices and their experiences, observations, and perceptions about climatic and environmental change and variability are relatively absent in the published literature to date. To address this gap, the goal of this research was to explore the observations and perceptions of climate change held by youth (12–25 years old) in the Inuit community of Rigolet, Nunatsiavut, Canada. Twenty in-depth interviews were conducted with youth in Rigolet to gather data about climatic and environmental changes young people have observed, and the subsequent impacts of these changes on their lives, culture, and community. Youth reported observing and experiencing climatic and environmental changes throughout their lives, with reported impacts falling within five main themes: changing travel conditions and access to hunting; challenges to Inuit culture; a concern for Elder and senior well-being; strong climate-related emotional responses; and youth-identified potential adaptation strategies. More broadly, this research demonstrated that young people have valuable knowledge and perspectives to offer. In particular, researchers, community leaders, and policy makers are encouraged to meaningfully engage youth as crucial stakeholders in future climate change work, research, dialogue, and policy. 相似文献
87.
Lydie Herfort Tawnya D. Peterson Fredrick G. Prahl Lee Ann McCue Joseph A. Needoba Byron C. Crump G. Curtis Roegner Victoria Campbell Peter Zuber 《Estuaries and Coasts》2012,35(3):878-891
The localized impact of blooms of the mixotrophic ciliate Myrionecta rubra in the Columbia River estuary during 2007–2010 was evaluated with biogeochemical, light microscopy, physiological, and molecular data. M. rubra affected surrounding estuarine nutrient cycles, as indicated by high and low concentrations of organic nutrients and inorganic nitrogen, respectively, associated with red waters. M. rubra blooms also altered the energy transfer pattern in patches of the estuarine water that contain the ciliate by creating areas characterized by high primary production and elevated levels of fresh autochthonous particulate organic matter, therefore shifting the trophic status in emergent red water areas of the estuary from net heterotrophy towards autotrophy. The pelagic estuarine bacterial community structure was unaffected by M. rubra abundance, but red waters of the ciliate do offer a possible link between autotrophic and heterotrophic processes since they were associated with elevated dissolved organic matter and showed a tendency for enhanced microbial secondary production. Taken together, these findings suggest that M. rubra red waters are biogeochemical hotspots of the Columbia River estuary. 相似文献
88.
Frances Westall Frédéric Foucher Sjoukje T. de Vries Victoria Pearson Alexander Verchovsky Jean-Noel Rouzaud Severine Anne 《Planetary and Space Science》2011,59(10):1093-479
Within the context of present and future in situ missions to Mars to investigate its habitability and to search for traces of life, we studied the habitability and traces of past life in ∼3.5 Ga-old volcanic sands deposited in littoral environments an analogue to Noachian environments on Mars. The environmental conditions on Noachian Mars (4.1-3.7 Ga) and the Early Archaean (4.0-3.3 Ga) Earth were, in many respects, similar: presence of liquid water, dense CO2 atmosphere, availability of carbon and bio-essential elements, and availability of energy. For this reason, information contained in Early Archaean terrestrial rocks concerning habitable conditions (on a microbial scale) and traces of past life are of relevance in defining strategies to be used to identify past habitats and past life on Mars.One such example is the 3.446 Ga-old Kitty’s Gap Chert in the Pilbara Craton, NW. Australia. This formation consists of volcanic sediments deposited in a coastal mudflat environment and is thus a relevant analogue for sediments deposited in shallow water environments on Noachian Mars. Two main types of habitat are represented, a volcanic (lithic) habitat and planar stabilized sediment surfaces in sunlit shallow waters. The sediments hosted small (<1 μm in size) microorganisms that formed colonies on volcanic particle surfaces and in pore waters within the volcanic sediments, as well as biofilms on stabilised sediment surfaces. The microorganisms included coccoids, filaments and rare rod-shaped organisms associated with microbial polymer (EPS). The preserved microbial community was apparently dominated by chemotrophic organisms but some locally transported filaments and filamentous mat fragments indicate that possibly photosynthetic mats formed nearby. Both microorganisms and sediments were silicified during very early diagenesis.There are no macroscopic traces of fossilised life in these volcanic sediments and sophisticated instrumentation and specialized sample preparation techniques are required to establish the biogenicity and syngenicity of the traces of past life. The fact that the traces of life are cryptic, and the necessity of using sophisticated instrumentation, reinforces the challenges and difficulties of in situ robotic missions to identify past life on Mars. We therefore recommend the return of samples from Mars to Earth for a definitive search for traces of life. 相似文献
89.
W. Victoria Lee 《Natural Hazards》2014,70(2):1453-1505
Extreme temperature events (ETEs) are important climatological natural disasters whose consequences have been largely underappreciated due to current challenges in defining them and measuring their impacts. Taking an exploratory approach, this study examines the historical records of 422 ETE occurrences across 71 countries in the period 1900–2011 from the International Disaster Database (EM-DAT) with more detailed analyses for records from 1971 to 2011. The various limitations associated with ETE data and the EM-DAT database are discussed and followed by analyses for heat and cold events. Globally, after adjusting for bias due to increased reporting, it was found that there may be genuine increases in ETE occurrences. Trends for mortality are much more uncertain, with possibly a higher increase for heat than for cold events if the high death counts of the 2003 and 2010 heat waves are included. If excluded, only mortality for cold seems to have increased over the years. Comparisons with other mortality databases suggest that EM-DAT’s global coverage may not be entirely complete. Furthermore, it may have underestimated numbers of death counts, especially for small-scale heat events and cold events in general. Further analyses by Human Development Index (HDI) categories also suggest two additional and opposing biases: an increased reporting bias for more developed nations and an underreporting bias for less developed nations. Country-level analyses based on both absolute and adjusted data suggest that a handful of countries have been most severely impacted by ETE. These mainly comprise developed nations but also include five medium- and low-HDI countries in Asia. 相似文献
90.
Galina V. Ledneva Victoria L. Pease Sergey D. Sokolov 《Journal of Asian Earth Sciences》2011,40(3):737-745
In order to test tectonic hypotheses regarding the evolution of the Arctic Alaska–Chukotka microplate prior to the opening of the Amerasian basin, we investigated rocks exposed near Kolyuchinskaya Bay, eastern Chukotka. Hypabyssal mafic rocks and associated basaltic flows enclose terrigenous sediments, minor cherts and limestones in pillow interstices. The hypabyssal mafic rock yields a U–Pb zircon age of 252 ± 4 Ma and indicates intrusion of basic magma at the Permo-Triassic boundary, contemporaneous with voluminous magmatism of the Siberian large igneous province (LIP). The lava flows and hypabyssal mafic rocks of the Kolyuchinskaya Bay region have trace elements, Sm–Nd and Rb–Sr isotope compositions identical to the tholeiitic flood basalts of the main plateau stage of the Siberian LIP, but differ from the latter in the major-element variations. We conclude that compositional variations in the hypabyssal rocks studied reflect their generation in an extensional environment that might be related to the Siberian super-plume activity at the time. Although the genetic and temporal links between intrusive mafic rocks and lavas are not well proved, compositional variations of the eruptive rocks still indicate their generation in an extensional environment. 相似文献