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381.
Storm surges: perspectives and options 总被引:4,自引:1,他引:3
This review paper attempts to summarize the scattered and fragmented knowledge about past and possible future changing storm-surge
statistics using the particularly well-studied case of the North Sea as an example. For this region, a complete and robust
analysis methodology has been developed in recent years. This methodology is based on dynamical and statistical models. Using
the concept of dynamical downscaling, development during recent decades, when sufficiently good and homogeneous weather data
exist, has been “reconstructed,” and scenarios of possible future change are described. “Localization” allows estimation of
changes at specific sites, e.g., harbors. As local water-level statistics depend not only on climate variations but also on
local modifications of the local bathymetry, new options for adaptation emerge. For the case of Hamburg, an option for such
future adaptations is discussed. 相似文献
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383.
Concentrations and sources of carbonaceous aerosol in the atmosphere of Summit,Greenland 总被引:1,自引:0,他引:1
Erika von Schneidemesser James J. Schauer Gayle S.W. Hagler Michael H. Bergin 《Atmospheric environment (Oxford, England : 1994)》2009,43(27):4155-4162
High-volume PM2.5 samples were collected at Summit, Greenland for approximately six months from late May through December of 2006. Filters were composited and analyzed for source tracer compounds. The individual organic compounds measured at Summit are orders of magnitude smaller than concentrations measured at other sites, including locations representative of remote oceanic, and remote and urban continental aerosol. The measured tracers were used to quantify the contribution of biomass burning (0.6–0.9 ng C m?3), vegetative detritus (0.3–0.9 ng C m?3), and fossil fuel combustion (0.1–0.8 ng C m?3) sources, 4% of OC total, to atmospheric organic carbon concentrations at the remote location of Summit, Greenland. The unapportioned organic carbon (96%) during the early summer period correlates well with the fraction of water soluble organic carbon, indicating secondary organic aerosol as a large source of organic carbon, supported by the active photochemistry occurring at Summit. To the author's knowledge, this paper represents the first source apportionment results for the polar free troposphere. 相似文献
384.
Biofuels are heavily debated as to their potential to reduce transport-related greenhouse gas emissions. Life cycle thinking gave rise to formal evaluations of the energy balance of such fuels, which led to the vigorously conducted “corn to ethanol” debates. Just as consensus was building on such evaluations came the “carbon debt” insights, a result of applying consequential Life Cycle Assessment (LCA) backed by advanced economic modeling. Increasingly, hopes have shifted to the 2nd generation biofuels, viewed as a “technological home run”. Could this also backfire? We investigate a simple South African case in which there might not be improvements in environmental performance: a sugar mill sells its bagasse, currently used at low efficiency to provide process heat, to an advanced biofuels producer, and buys an equivalent amount of coal without investing in efficiency improvements. Seven scenarios are generated, ranging from the status quo, where no bagasse is diverted, to 100% bagasse diversion, with one scenario including an energy efficiency improvement in the sugar mill. A consequential LCA is applied to the seven scenarios, covering global warming potential (GWP), non-renewable energy use, aquatic eutrophication and terrestrial acidification. A basic financial analysis of the proposed scenarios shows that they are realistic, with potentially lucrative returns. Results show that diverting bagasse without efficiency improvements from its current use to an ethanol bio-refinery would indeed backfire for all environmental impacts studied. The base case outperforms all the other scenarios, with the 100% bagasse diversion scenario emerging the worst. Investments into energy efficiency are therefore a precondition for diverting cellulosic residues into biofuel production. 相似文献
385.
B Sures S Zimmermann J Messerschmidt A von Bohlen F Alt 《Environmental pollution (Barking, Essex : 1987)》2001,113(3):341-345
Following the introduction of automobile catalysts in the middle of the 1980s in Germany there is an increasing emission of the platinum-group-metals platinum, palladium (Pd) and rhodium. Still, it remains unclear if these metals are bioavailable for aquatic animals and to which extent they become accumulated by the aquatic biosphere. Because of analytical problems in detecting Pd in small biological samples the present investigation concentrates on the bioavailability of this metal. To answer the question of a Pd uptake by aquatic organisms experimental studies were conducted with European eels maintained in water containing road dust at a concentration of 10 kg/100 l. Following an exposure period of four weeks, samples of liver and kidney were analysed by total-reflection X-ray fluorescence analysis after co-precipitation of Pd with mercury. These experiments revealed an uptake of traffic related Pd by European eels which showed a mean liver Pd concentration of 0.18 +/- 0.05 ng/g (wet wt.), whereas the Pd concentration in the kidney ranged below the detection limit. Thus, in this study we can demonstrate for the first time that automobile catalyst emitted Pd is bioavailable for aquatic animals. 相似文献
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388.
Jesko Partecke Arndt von Haeseler Martin Wikelski 《Behavioral ecology and sociobiology》2002,51(6):579-587
The territory establishment of male marine iguanas and their subsequent mating success were analysed to identify spatial spillover (hotshot) and temporal spillover effects on lek formation. Males started to establish small display territories 2 months ahead of the mating season. Males did not establish territories in temporal synchrony and did not settle at sites where the probability of encountering females was highest. However, males arriving later preferentially established their territories in the neighbourhood of already established territories independently of the density of female-sized iguanas in these territories. Although settling in close proximity, there were no fights between those males. The number of fights between territorial males increased towards, and peaked during, the mating season. Fights did not result in the transfer of space, indicating that space per se was no resource. Instead, fights were directed towards central (hotshot) males. These central males had higher mating success than marginal males. Female density during the time of territory establishment did not predict the mating success of males, because females changed their spatial preferences between early establishment and mating periods. Similarly, the areas where males achieved the highest numbers of copulations changed during 4 years of our study. Thus, there was no evidence for temporal spillover between subsequent seasons. However, most male-male interactions served to distract successful males and may lead to spatial spillover of females into territories of unsuccessful males. In marine iguanas, territorial establishment appears largely governed by hotshot processes. 相似文献
389.
390.
Mapping heavy metals in polluted soil by disjunctive kriging 总被引:16,自引:0,他引:16
von Steiger B Webster R Schulin R Lehmann R 《Environmental pollution (Barking, Essex : 1987)》1996,94(2):205-215
The soil of some 50 km(2) around the town of Weinfelden in north-east Switzerland has been sampled and analysed to estimate and map the concentrations of heavy metals before an incinerator for the canton's waste is built. Given that the estimates are subject to error, the probabilities that true values exceed the maximum tolerable concentrations of the Swiss federal guide have also been estimated by disjunctive kriging. These may now be used by the local planners for making decisions. Of the metals examined, lead exceeded the guide value at several sampling points, and a moderate probability of excess of lead is fairly widespread. Copper exceeded the guide value in vineyards and orchards, but also in a few places elsewhere, and the estimated probabilities of excess were not negligible. The other two metals of concern, cadmium (with one exception) and zinc, had concentrations much less than the guide values. The patterns of distribution of the four metals were similar, the product-moment correlations among them are substantial, except in the vineyards and orchards, and it seems likely that they had common sources. 相似文献