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The EU Emissions Trading System (ETS) demonstrated the ability to design and launch a large-scale trading system in a short period of time. The path from initial reticence about emissions trading to implementation of the world's largest program is an important history. Three issues play a large role in the evaluation of the program to date and its on-going development: allocation plans, cost uncertainty, and leakage of emissions to abroad. Decisions in Phase I and II (2005-2012) were responsive to questions of political feasibility and implementation, but some of these decisions including allocation in particular will be substantially revised in Phase III (2013-2020).  相似文献   
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The King Abdullah Canal (KAC) is an artificial water conveyor serving as raw water source for drinking water supply of Amman and for irrigation purposes in the Jordan Valley. The main water sources for KAC originate from the Yarmouk River, the Mukheiba Wells, and the Peace Conveyor. Water samples were collected from December 2002 to May 2004 to investigate changes in physicochemical parameters and parameters related to eutrophication along KAC. The catchment area of KAC is highly heterogeneous in terms of topography, climate, geologic conditions, and land use, resulting in great variations in the physicochemical composition of the canal water. The Yarmouk River and the Mukheiba Wells reflect the water quality of precipitation without much dissolution of halides, whereas the Peace Conveyor shows a groundwater characteristic. Main dischargers of N and P compounds are the Yarmouk River, and dams and wadis along KAC. The concentrations in the canal are mostly above eutrophication level for N and P. Along KAC there is an increase in chlorophyll a concentration and plankton counts. The formation potentials for trihalomethanes (THMs) and for integrated organically bound halogens are determined by chlorination to evaluate the consequences of water disinfection. Due to relatively high bromide concentration mainly brominated THMs are formed.  相似文献   
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We present a multi-model ensemble study for the Baltic Sea, and investigate the combined impact of changing climate, external nutrient supply, and fisheries on the marine ecosystem. The applied regional climate system model contains state-of-the-art component models for the atmosphere, sea ice, ocean, land surface, terrestrial and marine biogeochemistry, and marine food-web. Time-dependent scenario simulations for the period 1960–2100 are performed and uncertainties of future projections are estimated. In addition, reconstructions since 1850 are carried out to evaluate the models sensitivity to external stressors on long time scales. Information from scenario simulations are used to support decision-makers and stakeholders and to raise awareness of climate change, environmental problems, and possible abatement strategies among the general public using geovisualization. It is concluded that the study results are relevant for the Baltic Sea Action Plan of the Helsinki Commission.  相似文献   
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Floods in the northern foreland of the Tatra Mountains considerably contribute to the total flood damage in Poland. Therefore, the question whether the magnitude and frequency of floods have changed in this region is of high interest. This study aims at investigating the inter-decadal variability of magnitude, frequency and seasonality of floods since the mid-twentieth century, to better understand regional changes. The analysis was accomplished in a multi-temporal approach whereby trends are fitted to every possible combination of start and end years in a record. Detected trends were explained by estimating correlations between the investigated flood parameters and different large-scale climate indices for the northern hemisphere, and by trends found in intense precipitation indices, number of days with snow cover, cyclonic circulation types, temperature and moisture conditions. Catchment and channel changes that occurred in the region over the past decades were also considered. Results show that rivers in the area exhibit considerable inter-decadal variability of flows. The magnitude and direction of short-term trends are heavily influenced by this inter-decadal variability; however, certain patterns are apparent. More extreme, although perhaps less frequent floods are now likely to occur, with a shift in the seasonality, decreasing flood magnitudes in winter and increasing during autumn and spring. The identification of the factors contributing to the occurrence of flood events and their potential changes is valuable to enhance the flood management in the region and to improve the resilience of the population in this mountainous area.  相似文献   
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ABSTRACT

The spatial variability of different fractions of particulate matter (PM) was investigated in the city of Basel, Switzerland, based on measurements performed throughout 1997 with a mobile monitoring station at six sites and permanently recorded measurements from a fixed site. Additionally, PM10 measurements from the following year, which were concurrently recorded at two urban and two rural sites, were compared.

Generally, the spatial variability of PM4, PM10, and total suspended particulates (TSP) within this Swiss urban environment (area = 36 km2) was rather limited. With the exception of one site in a street canyon next to a traffic light, traffic density had only a weak tendency to increase the levels of PM. Mean PM10 concentration at six sites with different traffic densities was in the range of less than ±10% of the mean urban PM10 level. However, comparing the mean PM levels on workdays to that on weekends indicated that the impact of human activities, including traffic, on ambient PM levels may be considerable.

Differences in the daily PM10 concentrations between urban and more elevated rural sites were strongly influenced by the stability of the atmosphere. In summer, when no persistent surface inversions exist, differences between urban and rural sites were rather small. It can therefore be concluded that spatial variability of annual mean PM concentration between urban and rural sites in the Basel area may more likely be caused by varying altitude than by distance to the city center.  相似文献   
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