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101.
102.
Historical torrential flood events in the Kolubara river basin 总被引:1,自引:0,他引:1
103.
104.
105.
The aim of this paper is to investigate different aspects of the seasonal-to-interannual temperature variability in Eastern Patagonia, the southernmost area of South America, east of the Andes Cordillera. Homogenous regions of seasonal variability and the atmospheric circulation patterns associated with warm and cold conditions in each of them are described in this study. Relationships between temperature in Eastern Patagonia and that registered in other areas of southern South America are also addressed. Results show that the northern and southern areas of Eastern Patagonia have different temperature variability in summer and autumn whereas the temperature variability tends to be more homogeneous within the region during winter and spring. Warm (cold) conditions in the northern areas are associated with reinforced (weakened) westerlies in summer, winter and spring whereas northerly (southerly) advections of warm (cold) air toward the region produce such conditions in autumn. Temperature in the southern portion of Eastern Patagonia is affected by anticyclonic (cyclonic) anomalies that enhance (reduce) the incoming solar radiation and induce reinforced (weakened) westerlies promoting warm (cold) conditions in the region. Furthermore, cyclonic (anticyclonic) anomalies at subpolar latitudes hinder (favor) outbreaks of cold air increasing (decreasing) the temperature over areas of Eastern Patagonia. The circulation anomalies associated with warm (cold) conditions in Eastern Patagonia also promote cold (warm) conditions over areas of northern Argentina, Paraguay and southern Brazil. Consequently, a dipole of temperature is detected in southern South America with centers of opposite sign over these regions. 相似文献
106.
The existing United Nations Framework Convention on Climate Change (UNFCCC) has failed to deliver the rate of low-carbon technology transfer (TT) required to curb GHG emissions in developing countries. This failure has exposed the limitations of universalism and renewed interest in bilateral approaches to TT. Gaps are identified in the UNFCCC approach to climate change TT: missing links between international institutions and the national enabling environments that encourage private investment; a non-differentiated approach for (developing) country and technology characteristics; and a lack of clear measurements of the volume and effectiveness of TTs. Evidence from econometric literature and business experience on climate change TT is reviewed, so as to address the identified pitfalls of the UNFCCC process. Strengths and weaknesses of different methodological approaches are highlighted. International policy recommendations are offered aimed at improving the level of emission reductions achieved through TT. 相似文献
107.
The observational evidence given by Galileo spacecraft about Europa supports an icy rigid layer of several kilometers over
another ductile layer of ice in convection, which floats over an internal ocean of liquid water. Before the onset of convection,
heat is transmitted into the crust by conduction. The heat flow analysis in the potentially convective layer gives values
higher than those obtained previously by tidal dissipation models, and suggests that the ice may be limited to a thin layer
of ∼4 km total thickness.
This revised version was published online in July 2006 with corrections to the Cover Date. 相似文献
108.
Sediment disturbance patterns in the coastal area off the Tagus Estuary (Portugal) have been assessed using a set of combined techniques. The potential sources of disturbance in the area include chronic contamination of the fine sediments originating from the estuary, a local input from a long-sea sewage outfall and occasional high runoff episodes following torrential rain. The Sediment Quality Triad approach, combining environmental chemistry (namely organic contaminants), macrofaunal benthic communities and laboratory sediment toxicity assays, was performed on sediment samples from 20 sites. The samples were collected before the outfall commenced operation and four years after commissioning, in order to evaluate the relative magnitudes of the three potential sources of disturbance. The sediment contamination created by the estuary was identified as the most important cause of reduced sediment quality, as disturbance in all three components of the Sediment Quality Triad were only found in a site located near the estuary. 相似文献
109.
Carvalho S Gaspar MB Moura A Vale C Antunes P Gil O da Fonseca LC Falcão M 《Marine pollution bulletin》2006,52(11):1414-1424
This study reports the longitudinal distribution of sediment properties, including inorganic and organic contaminants, and the structure of the benthic community in Obidos lagoon, a coastal system permanently connected to the sea and with negligible freshwater sources. Sediments from the upper to central lagoon consist of fine particles (91%) and from the lower lagoon of sands (94%). Chemical composition is strongly correlated to the percentage of fine particles. Contamination is relatively low in those sediments suggesting the effect of diffuse sources. The increase in organic matter content from down- to upstream areas was associated with the dominance of opportunistic species, while sensitive and indifferent species to organic enrichment were mainly associated to the clean sandy downstream area. The marine biotic index (AMBI) was suitable for the discrimination of the biological and environmental gradients in the Obidos lagoon and was highly related with the gradient of organic matter content in this system. 相似文献
110.
Bioremediation and toxicity determination of natural seawater polluted with weathered crude oil by salt-tolerant consortia in a SBR 总被引:1,自引:0,他引:1
The aim of this research was to compare the bioremediation treatment of seawater polluted with two different concentrations of weathered crude oil (0.2 for experiment (a) and 1.14% for experiment (b), v/v) by salt-tolerant consortia enriched from the sludge of a refinery wastewater treatment facility, in a SBR. The use of a commercial bioremediation stimulant (S200) was also evaluated as an alternative to the traditional nitrogen and phosphorus supplement. 相似文献