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281.
The assessment of greenhouse gases (GHGs) emitted to and removed from the atmosphere is high on both political and scientific agendas internationally. As increasing international concern and cooperation aim at policy-oriented solutions to the climate change problem, several issues have begun to arise regarding verification and compliance under both proposed and legislated schemes meant to reduce the human-induced global climate impact. The approaches to addressing uncertainty introduced in this article attempt to improve national inventories or to provide a basis for the standardization of inventory estimates to enable comparison of emissions and emission changes across countries. Authors of the accompanying articles use detailed uncertainty analyses to enforce the current structure of the emission trading system and attempt to internalize high levels of uncertainty by tailoring the emissions trading market rules. Assessment of uncertainty can help improve inventories and manage risk. Through recognizing the importance of, identifying and quantifying uncertainties, great strides can be made in the process of Accounting for Climate Change.  相似文献   
282.
Greenhouse gas intensity is a ratio comparing the greenhouse gas (GHG) emissions of an activity or economic sector to the economic value it generates. In recent years, many countries have calculated the GHG intensity of their economic sectors as a basis for policy making. The GHG intensity of tourism, however, has not been determined since tourism is not measured as an economic sector in the national accounts. While for tourism-reliant countries it would be useful to know this quantity, a number of difficulties exist in its determination. In this study, we determine the GHG intensity of tourism's value added in Switzerland by means of a detailed bottom-up approach with the main methodological focus on how to achieve consistent system boundaries. For comparison, we calculate the tourism sector's GHG intensity for selected European countries using a simpler top-down approach. Our results show that the Swiss tourism sector is more than four times more GHG intensive than the Swiss economy on average. Of all tourism's sub-sectors, air transport stands out as the sector with by far largest emissions (80%) and highest GHG intensity. The results for other countries make similar, if not as pronounced, patterns apparent. We discuss the results and possible mitigation options against the background of the goal to prevent dangerous climate change.  相似文献   
283.
Social capacity building for natural hazards is a topic increasingly gaining relevance not only for so-called developing countries but also for European welfare states which are continuously challenged by the social, economic and ecological impacts of natural hazards. Following an outline of recent governance changes with regard to natural hazards, we develop a heuristic model of social capacity building by taking into account a wide range of existing expertise from different fields of research. Particular attention is paid to social vulnerability and its assessment, as well as to risk communication and risk education as specific strategies of social capacity building. We propose to distinguish between interventionist and participatory approaches, thus enabling for a better understanding of existing practices of social capacity building as well as their particular strengths and weaknesses. By way of conclusion, we encourage more research on social capacity building for natural hazards in the European context which at present is highly diverse and, at least in parts, only poorly investigated.  相似文献   
284.
285.
Protected areas (PAs) are often implemented without consideration of already existing PAs, which is likely to cause an overrepresentation of certain biophysical conditions. We assessed the representativeness of the current PA network with regard to the world's biophysical conditions to highlight which conditions are underprotected and where these conditions are located. We overlaid terrestrial and marine PAs with information on biophysical conditions (e.g., temperature, precipitation, and elevation) and then quantified the percentage of area covered by the PA network. For 1 variable at a time in the terrestrial realm, high temperature, low precipitation, and medium and very high elevation were underrepresented. For the marine realm, low and medium sea surface temperature (SST), medium and high sea surface salinity (SSS), and the deep sea were underrepresented. Overall, protection was evenly distributed for elevation across the terrestrial realm and SST across the marine realm. For 2 variables at a time, cold and very dry terrestrial environments had mostly low protection, which was also the case for low SST and low and medium SSS across most depths for marine environments. Low protection occurred mostly in the Sahara and the Arabian Peninsula for the terrestrial realm and along the Tropic of Capricorn and toward the poles for the marine realm. Although biodiversity measures are of prime importance for the design of PA networks, highlighting biophysical gaps in current PAs adds a frequently overlooked perspective. These gaps may weaken the potential of PAs to conserve biodiversity. Thus, our results may provide useful insights for researchers, practitioners, and policy makers to establish a more comprehensive global PA network.  相似文献   
286.
Environmental Chemistry Letters - Microplastics are recently discovered contaminants, yet knowledge on their sources and analysis is limited. For instance, paint microplastics are poorly known...  相似文献   
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