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981.
Staying cool in a changing climate: Reaching vulnerable populations during heat events 总被引:1,自引:0,他引:1
Natalie R. Sampson Carina J. Gronlund Miatta A. Buxton Linda Catalano Jalonne L. White-Newsome Kathryn C. Conlon Marie S. O’Neill Sabrina McCormick Edith A. Parker 《Global Environmental Change》2013,23(2):475-484
The frequency and intensity of hot weather events are expected to increase globally, threatening human health, especially among the elderly, poor, and chronically ill. Current literature indicates that emergency preparedness plans, heat health warning systems, and related interventions may not be reaching or supporting behavior change among those most vulnerable in heat events. Using a qualitative multiple case study design, we comprehensively examined practices of these populations to stay cool during hot weather (“cooling behaviors”) in four U.S. cities with documented racial/ethnic and socio-economic disparities and diverse heat preparedness strategies: Phoenix, Arizona; Detroit, Michigan; New York City, New York; and Philadelphia, Pennsylvania. Based on semi-structured in-depth interviews we conducted with 173 community members and organizational leaders during 2009–2010, we assessed why vulnerable populations do or do not participate in health-promoting behaviors at home or in their community during heat events, inquiring about perceptions of heat-related threats and vulnerability and the role of social support. While vulnerable populations often recognize heat's potential health threats, many overlook or disassociate from risk factors or rely on experiences living in or visiting warmer climates as a protective factor. Many adopt basic cooling behaviors, but unknowingly harmful behaviors such as improper use of fans and heating and cooling systems are also adopted. Decision-making related to commonly promoted behaviors such as air conditioner use and cooling center attendance is complex, and these resources are often inaccessible financially, physically, or culturally. Interviewees expressed how interpersonal, intergenerational relationships are generally but not always protective, where peer relationships are a valuable mechanism for facilitating cooling behaviors among the elderly during heat events. To prevent disparities in heat morbidity and mortality in an increasingly changing climate, we note the implications of local context, and we broadly inform heat preparedness plans, interventions, and messages by sharing the perspectives and words of community members representing vulnerable populations and leaders who work most closely with them. 相似文献
982.
Donald B. Percival Donald W. Denbo Marie C. Eblé Edison Gica Harold O. Mofjeld Michael C. Spillane Liujuan Tang Vasily V. Titov 《Natural Hazards》2011,58(1):567-590
The ability to accurately forecast potential hazards posed to coastal communities by tsunamis generated seismically in both
the near and far field requires knowledge of so-called source coefficients, from which the strength of a tsunami can be deduced.
Seismic information alone can be used to set the source coefficients, but the values so derived reflect the dynamics of movement
at or below the seabed and hence might not accurately describe how this motion is manifested in the overlaying water column.
We describe here a method for refining source coefficient estimates based on seismic information by making use of data from
Deep-ocean Assessment and Reporting of Tsunamis (DART
\circledR^{\circledR}) buoys (tsunameters). The method involves using these data to adjust precomputed models via an inversion algorithm so that
residuals between the adjusted models and the DART
\circledR^{\circledR} data are as small as possible in a least squares sense. The inversion algorithm is statistically based and hence has the
ability to assess uncertainty in the estimated source coefficients. We describe this inversion algorithm in detail and apply
it to the November 2006 Kuril Islands event as a case study. 相似文献
983.
Impacts on agriculture following the 1991 eruption of Vulcan Hudson, Patagonia: lessons for recovery 总被引:1,自引:1,他引:0
Thomas Wilson Jim Cole Shane Cronin Carol Stewart David Johnston 《Natural Hazards》2011,57(2):185-212
Large explosive eruptions have the potential to distribute heavy ashfalls across large areas, resulting in physical and chemical impacts on agriculture, and economic and psycho-social impacts on rural communities. This study investigates how affected agriculture and rural communities have adapted, absorbed and mitigated impacts following a range of ashfall thicknesses (>2 m?C<1 mm) from the 12?C15 August 1991 eruption of Vulcan Hudson, one of the largest eruptions of the twentieth century. An estimated 1 million livestock died after the eruption due to pasture burial by ashfall and ongoing suppression of vegetation recovery. Horticulturalists suffered ongoing damage to crops from wind-blown ash and changes to soil properties increased irrigation and cultivation requirements. Real or perceived impacts on human health and impacts on farm productivity from the ashfall resulted in evacuation of farms and small towns in the short term. Long-term farm abandonment occurred in areas of heavy ashfall (upper Ibáñez valley) and highly stressed farming systems, even where ashfall was relatively thin (<50 mm), such as the Argentine steppe. The mono-agricultural system of sheep farming in the steppe region had few options other than destocking, proving less resilient than the diverse high-intensity horticultural and pastoral mix in irrigated valleys, which allowed more rapid adaption through diversification of production. Farms with natural advantages and greater investment in capital improvements led to greater damage potential initially (at least in cost terms), but ultimately provided a greater capacity for response and recovery. Better soils, climate and significantly greater access to technological improvements such as cultivation tools, irrigation and wind breaks were advantageous, such as at Chile Chico (Chile), Los Antiguos and Perito Moreno (Argentina). Cultivation increased chemical and physical soil fertility, especially when used in combination with fertilisation and irrigation. Appropriate use of seeds and cropping techniques within the new soil and growing conditions was important. Government agencies had a vital role in the dissemination of information for appropriate farm management responses, ash chemistry analysis, evacuations and welfare, and in the longer term to provide technical and credit assistance to facilitate recovery. 相似文献
984.
A. Scott Morris Stephanie M. Wilson Erik F. Dever Randolph M. Chambers 《Estuaries and Coasts》2011,34(2):386-390
The effectiveness of bycatch reduction devices (BRDs) on commercial pots designed to capture blue crabs Callinectes sapidus was tested in the York River on Felgates Creek (37.2667 N, −76.5850 W) over the period 4 June through 31 July 2009. For each
of 10 pairs of pots, one had BRDs affixed to all four entrance gapes and the other had none. Pots were baited approximately
once each week but were sampled for blue crabs and bycatch 6 of 7 days each week for the duration of the study. More than
one fourth of 1,643 total crabs were caught on the first day after baiting, and for these 7 days, no statistical difference
was detected between either the number or size of legal-size crabs caught in BRD versus non-BRD pots. Of 51 Malaclemys terrapin and 44 fish caught as bycatch throughout the study, all but three fish were captured in non-BRD pots. BRDs exclude bycatch
and may reduce incidental mortality of crabs in pots that are not tended regularly. 相似文献
985.
Anne Marie de Grosbois 《Environmental Earth Sciences》2011,62(3):673-678
Events
Upcoming international events 相似文献986.
Daphne Cuvelier Pierre‐Marie Sarradin Jozée Sarrazin Ana Colaço Jon T. Copley Daniel Desbruyères Adrian G. Glover Ricardo Serrão Santos Paul A. Tyler 《Marine Ecology》2011,32(2):243-255
The Eiffel Tower edifice is situated in the Lucky Strike hydrothermal vent field at a mean depth of 1690 m on the Mid‐Atlantic Ridge (MAR). At this 11‐m‐high hydrothermal structure, different faunal assemblages, varying in visibly dominant species (mussels and shrimp), in mussel size and in density of mussel coverage, were sampled biologically and chemically. Temperature and sulphide (∑S) were measured on the different types of mussel‐based assemblages and on a shrimp‐dominated assemblage. Temperature was used as a proxy for calculating total concentrations of CH4. Based on the physico‐chemical measurements, two microhabitats were identified, corresponding to (i) a more variable habitat featuring the greatest fluctuations in environmental variables and (ii) a second, more stable, habitat. The highest temperature variability and the highest maximum recorded temperatures were found in the assemblages visibly inhabited by alvinocaridid shrimp and dense mussel beds of large Bathymodiolus azoricus, whereas the less variable habitats were inhabited by smaller‐sized mussels with increasing bare surface in between. Larger mussels appeared to consume more ∑S compared with smaller‐sized (<1 cm) individuals and thus had a greater influence on the local chemistry. In addition, the mussel size was shown to be significantly positively correlated to temperature and negatively to the richness of the associated macrofauna. The presence of microbial mats was not linked to specific environmental conditions, but had a negative effect on the presence and abundance of macro‐fauna, notably gastropods. Whereas some taxa or species are found in only one of the two microhabitats, others, such as polychaetes and Mirocaris shrimp, cross the different microhabitats. Temperature was proposed to be a more limiting factor in species distribution than ∑S. 相似文献
987.
Rachel Tiller 《Ocean & Coastal Management》2011,54(5):374-380
The Svalbard Fisheries Protection Zone is an international institution on the brink of being challenged in a critical phase of being institutionalized as a Norwegian property regime. The potential disturbance comes from the zooplankton redfeed, a new and valuable resource harvestable within the zone. Though the pressures on Norway’s inspection routines in the zone are challenged at times, this article suggests that the zone as a management regime is a surprisingly robust institution still. Nevertheless, in such a critical phase it is important not to allow possible exogenous shocks to appear, and creating a separate redfeed regime for the plankton will allow the Norwegian government to bypass this possible disturbance and allow for continued solidification of the zone into an EEZ for Norway. 相似文献
988.
Scott J. Wilson Robert B. HunterTimothy S. Collett Steve HancockRay Boswell Brian J. Anderson 《Marine and Petroleum Geology》2011,28(2):460-477
A series of gas hydrate development scenarios were created to assess the range of outcomes predicted for the possible development of the “Eileen” gas hydrate accumulation, North Slope, Alaska. Production forecasts for the “reference case” were built using the 2002 Mallik production tests, mechanistic simulation, and geologic studies conducted by the US Geological Survey. Three additional scenarios were considered: A “downside-scenario” which fails to identify viable production, an “upside-scenario” describes results that are better than expected. To capture the full range of possible outcomes and balance the downside case, an “extreme upside scenario” assumes each well is exceptionally productive.Starting with a representative type-well simulation forecasts, field development timing is applied and the sum of individual well forecasts creating the field-wide production forecast. This technique is commonly used to schedule large-scale resource plays where drilling schedules are complex and production forecasts must account for many changing parameters. The complementary forecasts of rig count, capital investment, and cash flow can be used in a pre-appraisal assessment of potential commercial viability.Since no significant gas sales are currently possible on the North Slope of Alaska, typical parameters were used to create downside, reference, and upside case forecasts that predict from 0 to 71 BM3 (2.5 tcf) of gas may be produced in 20 years and nearly 283 BM3 (10 tcf) ultimate recovery after 100 years.Outlining a range of possible outcomes enables decision makers to visualize the pace and milestones that will be required to evaluate gas hydrate resource development in the Eileen accumulation. Critical values of peak production rate, time to meaningful production volumes, and investments required to rule out a downside case are provided. Upside cases identify potential if both depressurization and thermal stimulation yield positive results. An “extreme upside” case captures the full potential of unconstrained development with widely spaced wells. The results of this study indicate that recoverable gas hydrate resources may exist in the Eileen accumulation and that it represents a good opportunity for continued research. 相似文献
989.
Hugo Delile Abdelhakim Abichou Ahmed Gadhoum Jean‐Philippe Goiran Elisa Pleuger Jean‐Yves Monchambert Andrew Wilson Elizabeth Fentress Josephine Quinn Imed Ben Jerbania Faouzi Ghozzi 《Geoarchaeology》2015,30(4):291-306
Although the ancient site of Utica has been studied since the 19th century, the location of its harbors remains unresolved as they were buried under sediments as the Mejerda delta prograded and left Utica 10 km inland. Using relief data and a coring survey with sedimentological analysis, we identify the dynamics of the delta's progradation, which produced a double system of alluvial fans. These show that the ancient bay of Utica silted up faster and earlier than was thought, probably before the end of the Punic period. Combined with the radiocarbon dates from coring, this suggests that the harbor lay on the north‐western side of the Utica promontory, communicating with the sea by a marine corridor west of the northern compartment of the delta. As the infilling of the ancient bay progressed, this corridor narrowed until it disappeared completely in the early 5th/mid‐6th century A.D., when a peat bog developed on the northern side of the promontory, sealing the fate of Utica as a port. This relative environmental stability ended in the 9th–10th century A.D. when about 4 m of sediment, probably of fluvial origin, covered the peat bog, leaving the site more than 4.5 m above the local sea level. 相似文献
990.
The St. Lawrence Iroquoians built villages in southwestern Quebec (Canada) along the St. Lawrence River. They left behind longhouses, hearths, middens, and storage pits like those discovered at the Mailhot‐Curran archaeological site in Saint‐Anicet. Here, we contrast the properties of Iroquoian features with undisturbed soil to define the chemical and mineralogical signature of hearths, middens, and pits. The native soil has a neutral pH and consists of an Ah horizon overlaying a Bm horizon dominated by quartz and feldspars. In the hearths, ashes are characterized by neoformed calcite and apatite with carbonates, higher total P, and enrichment in amorphous inorganic Al, Fe, and Si. The rubified layer of hearths contain poorly crystallized Fe oxides. The mineralogy of the rubified layer is dominated by authigenetic ankerite, an Fe‐carbonate mineral identified here for the first time in Iroquoian hearths. Middens have the highest organic matter content and contain more organically complexed Al and Fe than the soil. The storage pits have low pH values and carbonate content and contain high levels of amorphous Si and total P. Our work establishes the pedologic signature of three Iroquoian features despite significant alteration of their properties by post‐occupational biogeochemical processes. 相似文献