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301.
A practitioner's guide to a low-carbon economy: lessons from the UK   总被引:1,自引:0,他引:1  
Drawing primarily on the UK experience, five practical lessons are identified for policy makers who seek to decarbonize their economies. First, decarbonization needs a solid legal basis to give it credibility and overcome time inconsistency problems. Second, putting a price on carbon is essential, but low-carbon policies also have to address wider market, investment, and behavioural failures. This in turn raises issues of policy complexity and coordination. Third, the low-carbon economy is likely to be highly electrified. Clean electricity could be a cost-effective way of decarbonizing many parts of the economy, including transport, heating, and parts of industry. Decarbonization therefore starts in the power sector. Fourth, the low-carbon transition is primarily a revolution of production and not consumption. Both supply-side innovation and demand-side adjustments in lifestyle and behaviour are needed, though the former should dominate. Fifth, the transition to a low-carbon economy is economically and technologically feasible. Achieving it is a question of policy competence and having the political will to drive economic and social change.

Policy relevance

Practically all major GHG emitters now have climate change legislation on their statute books. Given what is at stake, and the complexity of the task at hand, it is important that policy makers learn from each other and establish a code of good low-carbon practice. The main lessons from the UK are distilled and presented. Carbon policy is considered for key sectors, such as electricity, buildings, and transport, and possible decarbonization paths are also outlined. It is shown that the transition to a low-carbon economy is economically and technologically feasible. Achieving it is primarily a question of policy competence and political will. This in turn means that climate change action needs a strong legislative basis to give the reforms statutory legitimacy. Low-carbon policies will have to address a wide range of market, investment and behavioural failures. Putting a price on carbon is an essential starting point, but only one of many policy reforms.  相似文献   
302.
The study area occupies a part in southern Ilesa and is located within the schist belt of southwestern Nigeria, which embraces undifferentiated schist, gneisses, and migmatites with pegmatites, schist and epidorite complex, quartzite and quartz schist, granite gneiss, amphibolite, pegmatised schist, granulite, and gneiss. The study is aimed at clarifying the potential source of mineralization dealt with before in regional studies. Sixty-one soil samples were collected and analyzed for identifying these elements: Pb, Fe, Ni, Cd, Cr, Cu, Zn, and Mn. Multivariate analysis was done to obtain the coefficients of principal components from the standardized variables The elemental associations from the principal components analysis that accounted for 85.34% variability of the total variance are: Fe–Mn, Pb–Cr, and Cd–Zn. Comparably, these are equivalent with the previous results in the amphibolites and added the extension of association region to involve the schist and epidorite complex, quartzite, and quartz schist. The metallic association ratio revealed high metallic concentrations and led to the mineralization trend in southern Ilesa.  相似文献   
303.
The Guole biota contains common shelly fossils and some exceptionally well-preserved soft-bodied fossils. Stratigraphically, it is located in the mudstones and siltstones of the Sandu Formation near Guole Town, Jingxi County, Guangxi, South China. It is the first Furongian (late Cambrian) Burgess Shale-type biota found in the world, thereby filling the gap between middle Cambrian and Lower Ordovician Burgess Shale-type Lagerst?tten. Preliminary studies suggest that the Guole biota includes approximately seven metazoan groups as well as algae. These will provide important new evolutionary and ecological information.  相似文献   
304.
We model the chemical and spectrophotometric evolution of the Milky Way, spiral galaxies and Low Surface Brightness Galaxies in a consistent way. Some consequences with respect to the nature of Damped Lyman-α systems (DLAs) are investigated. This revised version was published online in September 2006 with corrections to the Cover Date.  相似文献   
305.
In this study, the Land Use Dynamic Simulator model was applied to investigate the impact of farm credit as an adaptation strategy to cope with effects of climate variability on agricultural land‐use change and crop production in the Vea watershed in Ghana. The authors identified the determinants of crop choices within the landscape (e.g., farm household and biophysical characteristics of farm plot). The crop choice sub‐model was then linked to the crop yield sub‐model to determine the yields of selected crops. In adapting to the impacts of climate variability, the maize credit adoption sub‐model under the maize cultivation credit scenario was integrated into decision‐making. This was simulated for a 20‐year period, and compared with the business‐as‐usual scenario. Under the simulated maize credit scenario, maize adopters increased from about 20 per cent to about 50 per cent and the area allocated for maize cultivation significantly increased by about 266 per cent. Consequently, the average annual aggregated household crop yield increased by 6.3 per cent higher than in the business‐as‐usual scenario. This simulation study shows that access to maize credit can significantly influence agricultural land‐use change and food availability in the study area. However, although access to farm credit may translate into food availability, the sustainability of this strategy is questionable.  相似文献   
306.
Eclogite occurs within the southern domain of the East Athabasca mylonite triangle in northern Saskatchewan. Situated at the boundary between the Archean Rae and Hearne Provinces of the western Canadian Shield, the East Athabasca mylonite triangle is a fundamental exposure of the ~3,000-km-long Snowbird tectonic zone. The eclogite occurs in association with a variety of lower crustal high-pressure granulites that record a complex metamorphic history from 2.6 to 1.9 Ga. Temperatures of the eclogite facies metamorphism are constrained by garnet-clinopyroxene exchange thermometry at 920–1,000 °C. Minimum pressure conditions are recorded by the jadeite+quartz=albite geobarometer at 1.8–2.0 GPa. A near-isothermal decompression path to granulite facies conditions is inferred from retrograde reaction textures involving the formation of granulite facies assemblages such as orthopyroxene-plagioclase and pargasite-plagioclase. U-Pb IDTIMS zircon geochronology of the eclogite yields a weighted mean 207Pb/206Pb date of 1,904.0±0.3 Ma, which we interpret as the time of peak eclogite facies metamorphism. SHRIMP in situ analyses of metamorphic zircons included within omphacitic clinopyroxene support this interpretation with a weighted mean 207Pb/206Pb date of 1,905±19 Ma. Inclusion suites of high-pressure phases and the petrographic setting of zircon are a direct link between zircon growth and eclogite facies metamorphism. Zircon from one eclogite sample has older cores that are 2.54 Ga, which is a minimum age for the emplacement or earliest metamorphism of the gabbroic protolith. U-Pb rutile data indicate slow cooling at ~1°C/Ma below ~500 °C from 1.88 to 1.85 Ga. The formation and exhumation of the eclogites at ca.1.9 Ga has important implications for the tectonic significance of the Snowbird tectonic zone during the Paleoproterozoic. The eclogites described here are consistent with transport of continental crust to mantle depths during the Paleoproterozoic, followed by rapid buoyancy-driven exhumation to normal lower crustal depths.Editorial responsibility: T.L. Grove  相似文献   
307.
The number of climate change laws in major economies has grown from less than 40 in 1997 to almost 500 at the end of 2013. The passage of these laws is influenced by both domestic and international factors. This article reviews the main international factors, drawing on a powerful new dataset of climate legislation in 66 national jurisdictions. We find that the propensity to legislate on climate change is heavily influenced by the passage of similar laws elsewhere, suggesting a strong and so far under-appreciated role for international policy diffusion. International treaties such as the Kyoto Protocol work in two ways. The impact of the Kyoto Protocol itself is limited to countries with formal obligations under the treaty. In addition, the prestige of hosting an international climate summit is associated with a subsequent boost in legislation. Legislators seem to respond to the expectations of climate leadership that these events bestow on their host.

Policy relevance

A global solution to climate change will ultimately have to be anchored in domestic legislation, which creates the legal basis for countries to take action. Countries are passing climate legislation in a growing number. This article asks to what extent they are motivated to do so by international factors, such as existing treaty obligations. We find that the Kyoto Protocol has been a less important factor in explaining climate legislation outside Annex I than the passage of similar laws elsewhere. This suggests that international policy diffusion plays an important and so far under-appreciated role in global climate policy, complementing formal treaty obligations.  相似文献   

308.
Potential death from traffic collisions is a common hazard faced by nearly everyone. This analysis uses geographical approaches to examine fatal collision risk in the state of Indiana from 2003 to 2011. The state averaged 757 fatal collisions annually. About 60 percent occurred in urban or suburban areas. Risk was highest in low-density exurban and rural areas and on highways, county roads, and interstates. County sheriffs and state police were more likely to face fatal collisions than municipal police. Significant black spots existed around the Illinois and Kentucky state lines. Fatal collisions were less clustered than nonfatal collisions. Fatal collisions exhibited positive spatial autocorrelation but the global Moran's I for counties was close to random. Approximately 10 percent of ninety-two counties had significant local spatial autocorrelation in fatal collision rates. Police and emergency response resource distributions should be considered in light of fatal collision black spots in the state.  相似文献   
309.
310.
Ulysses plasma electron observations of bidirectional and enhanced unidirectional electron heat fluxes within 4500 RJ (0.8 a.u. or 3 months on either side of closest approach) of Jupiter are presented as evidence for the magnetic connection of the spacecraft to the Jovian bow shock. These bursts of suprathermal electrons (> 30 eV) are observed when the interplanetary magnetic field points roughly parallel or antiparallel to the Jupiter-spacecraft line. Ninety-eight possible connection events were found over the 6 month period centered on the closest approach to Jupiter. The frequency of occurrence peaked with proximity to the bow shock, with most events occurring post-encounter. These are the first observations of backstreaming suprathermal electrons made in the vicinity of the Jovian bow shock.  相似文献   
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