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91.
92.
Caroline Kivimäe Richard G.J. Bellerby Agneta Fransson Marit Reigstad Truls Johannessen 《Deep Sea Research Part I: Oceanographic Research Papers》2010,57(12):1532-1542
The first carbon budget constructed for the Barents Sea to study the fluxes of carbon into, out of, and within the region is presented. The budget is based on modelled volume flows, measured dissolved inorganic carbon (DIC) concentration, and literature values for dissolved organic carbon (DOC) and particulate organic carbon (POC) concentrations. The results of the budget show that ~5600±660×106 t C yr?1 is exchanged through the boundaries of the Barents Sea. If a 40% uncertainty in the volume flows is included in the error calculation it resulted in a total uncertainty of ±1600×106 t C yr?1. The largest part of the total budget flux consists of DIC advection (~95% of the inflow and ~97% of the outflow). The other sources and sinks are, in order of importance, advection of organic carbon (DOC+POC; ~3% of both in- and outflow), total uptake of atmospheric CO2 (~1% of the inflow), river and land sources (~0.2% of the inflow), and burial of organic carbon in the sediments (~0.2% of the outflow). The Barents Sea is a net exporter of carbon to the Arctic Ocean; the net DIC export is ~2500±660×106 t C yr?1 of which ~1700±650×106 t C yr?1 (~70%) is in subsurface water masses and thus sequestered from the atmosphere. The net total organic carbon export to the Arctic Ocean is ~80±20×106 t C yr?1. Shelf pumping in the Barents Sea results in an uptake of ~22±11×106 t C yr?1 from the atmosphere which is exported out of the area in the dense modified Atlantic Waters. The main part of this carbon was channelled through export production (~16±10×106 t C yr?1). 相似文献
93.
Natural Hazards - Over the past decade, the cost of disasters on lives and livelihoods has increased many folds. However, there are few tools available that can be used to measure the level of... 相似文献
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95.
Michael K. Weisberg Caroline Smith Gretchen Benedix Christopher D. K. Herd Kevin Righter Henning Haack Akira Yamaguchi Hasnaa Chennaoui Aoudjehane Jeffrey N. Grossman 《Meteoritics & planetary science》2009,44(9):1355-1397
Abstract— The Meteoritical Bulletin No. 96 contains a total of 1590 newly approved meteorite names with their relevant data. These include 12 from specific locations within Africa, 76 from northwest Africa, 9 from the Americas, 13 from Asia, 1 from Australia, 2 from Europe, 950 from Antarctica recovered by the Chinese Antarctic Research Expedition (CHINARE), and 527 from the American Antarctic program (ANSMET). Among these meteorites are 4 falls, Almahata Sitta (Sudan), Sulagiri (India), Ash Creek (United States), and Maribo (Denmark). Almahata Sitta is an anomalous ureilite and is debris from asteroid 2008 TC3 and Maribo is a CM2 chondrite. Other highlights include a lunar meteorite, a CM1 chondrite, and an anomalous IVA iron. 相似文献
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Michael K. WEISBERG Caroline SMITH Gretchen BENEDIX Christopher D. K. HERD Kevin RIGHTER Henning HAACK Akira YAMAGUCHI Hasnaa CHENNAOUI AOUDJEHANE Jeffrey N. GROSSMAN 《Meteoritics & planetary science》2010,45(3):449-493
Abstract– In this edition of The Meteoritical Bulletin, a total of 506 newly approved meteorite names with their relevant data are reported. These include 354 from northwest Africa, 31 from the Americas, 15 from Antarctica (Koreamet), 85 from Asia, 20 from Australia, and 1 from Europe. Among these meteorites are 2 falls, Grimsby (Canada) and Santa Lucia (2008) (Argentina). Also described are a CM with low degree of alteration, new ungrouped chondrites and achondrites, and 4 Martian meteorites. 相似文献
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99.
A three-dimensional finite-volume ELLAM method has been developed, tested, and successfully implemented as part of the U.S. Geological Survey (USGS) MODFLOW-2000 ground water modeling package. It is included as a solver option for the Ground Water Transport process. The FVELLAM uses space-time finite volumes oriented along the streamlines of the flow field to solve an integral form of the solute-transport equation, thus combining local and global mass conservation with the advantages of Eulerian-Lagrangian characteristic methods. The USGS FVELLAM code simulates solute transport in flowing ground water for a single dissolved solute constituent and represents the processes of advective transport, hydrodynamic dispersion, mixing from fluid sources, retardation, and decay. Implicit time discretization of the dispersive and source/sink terms is combined with a Lagrangian treatment of advection, in which forward tracking moves mass to the new time level, distributing mass among destination cells using approximate indicator functions. This allows the use of large transport time increments (large Courant numbers) with accurate results, even for advection-dominated systems (large Peclet numbers). Four test cases, including comparisons with analytical solutions and benchmarking against other numerical codes, are presented that indicate that the FVELLAM can usually yield excellent results, even if relatively few transport time steps are used, although the quality of the results is problem-dependent. 相似文献
100.
Poverty and Disasters in the United States: A Review of Recent Sociological Findings 总被引:2,自引:3,他引:2
This article synthesizes the literature on poverty and disasters in the United States and presents the results from a wide range of studies conducted over the past twenty years. The findings are organized into eight categories based on the stages of a disaster event. The review illustrates how people of different socioeconomic statuses perceive, prepare for, and respond to natural hazard risks, how low-income populations may be differentially impacted, both physically and psychologically, and how disaster effects vary by social class during the periods of emergency response, recovery, and reconstruction. The literature illustrates that the poor in the United States are more vulnerable to natural disasters due to such factors as place and type of residence, building construction, and social exclusion. The results have important implications for social equity and recommendations for future research and policy implementation are offered. 相似文献