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1.
SOCIAL BARRIERS TO RENEWABLE ENERGY LANDSCAPES*   总被引:2,自引:0,他引:2  
After many years of slow progress, we find that worldwide environmental, political, and economic pressures are providing greater purchase for the accelerated development of renewable energy. Although many people would consider this quickening pace good news, the transition from conventional resources has encountered public resistance. In this article I examine the nature of challenges to the development of geothermal, wind, and solar energy projects in three places: the United States, Scotland, and Mexico. The common thread in the public reservations about renewable energy is landscape change and the consequent disruption such change produces to established ways of life for those who are nearby. It also suggests the importance of rebalancing the emphasis of renewable energy programs away from the traditional technical focus that dominates development planning. The more suitable and expedient approach would be to consider the challenges of development as predominantly social matters with technical components, rather than the other way around. To accept this view is to unlock the door to a renewable energy future.  相似文献   
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The analysis of texture, major element and oxygen isotope compositions of cloudy garnet crystals from a metapelite sampled on Ikaria Island (Greece) is used to assess the model of growth and re‐equilibration of these garnet crystals and to reconstruct the pressure–temperature–fluid history of the sample. Garnet crystals show complex textural and chemical zoning. Garnet cores (100–200 μm) are devoid of fluid inclusions. They are characterized by growth zoning demonstrated by a bell‐shaped profile of spessartine component (7–3 mol.%), an increase in grossular from 14 to 22 mol.% and δ18O values between 9.5 ± 0.3‰ and 10.4 ± 0.2‰. Garnet inner rims (90–130 μm) are fluid inclusion‐rich and show a decreasing grossular component from 22 to 5 mol.%. The trend of the spessartine component observed in the inner rim allows two domains to be distinguished. In contrast to domain I, where the spessartine content shows the same trend as in the core, the spessartine content of domain II increases outwards from 2 to 14 mol.%. The δ18O values decrease towards the margins of the crystals to a lowest value of 7.4 ± 0.2‰. The outer rims (<10 μm) are devoid of fluid inclusions and have the same chemical composition as the outermost part of domain II of the inner rim. Garnet crystals underwent a four‐stage history. Stage 1: garnet growth during the prograde path in a closed system for oxygen. Garnet cores are remnants of this growth stage. Stage 2: garnet re‐equilibration by coupled dissolution–reprecipitation at the temperature peak (630 < T < 650 °C). This causes the creation of porosity as the coupled dissolution–reprecipitation process allows chemical (Ca) and isotopic (O) exchange between garnet inner rims and the matrix. The formation of the outer rim is related to the closure of porosity. Stage 3: garnet mode decreases during the early retrograde path, but garnet is still a stable phase. The resulting garnet composition is characterized by an increasing Mn content in the inner rim’s domain II caused by intracrystalline diffusion. Stage 4: dissolution of garnet during the late retrograde path as garnet is not a stable phase anymore. This last stage forms corroded garnet. This study shows that coupled dissolution–reprecipitation is a possible re‐equilibration process for garnet in metamorphic rocks and that intra‐mineral porosity is an efficient pathway for chemical and isotopic exchange between garnet and the matrix, even for otherwise slow diffusing elements.  相似文献   
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Which actors in the aviation sector ought to be obliged to participate in emissions trading? The European Commission opted for the aircraft operator in their proposal for a Directive. A major drawback is that non-EU aircraft operators might legally challenge their inclusion in this scheme and, if the challenge was successful, discrimination between EU and non- EU operators would undermine the scheme. An alternative would be to place an obligation on fuel suppliers to prove possession of allowances, thus avoiding discrimination. However, emissions trading can be evaded to some extent by increased refuelling beyond EU boundaries (tankering). Typical city pairs were used to analyse the conditions under which such tankering strategies are economically attractive. The analysis shows that the attractiveness of tankering depends substantially on the relationship between fuel prices and allowance prices. If the price relation as of March 2006 is taken as a basis, tankering would be attractive within a radius of up to 4,000 km especially on southbound and eastward routes. Emissions trading could, under unfavourable conditions, be evaded for up to 20% of the total fuel consumption in aviation with the help of tankering. Although this value is only a theoretical upper limit, more than 10% of fuel consumption could be affected by tankering.  相似文献   
5.
We demonstrate that there is significant skill in the GloSea5 operational seasonal forecasting system for predicting June mean rainfall in the middle/lower Yangtze River basin up to four months in advance.Much of the rainfall in this region during June is contributed by the mei-yu rain band.We find that similar skill exists for predicting the East Asian summer monsoon index(EASMI)on monthly time scales,and that the latter could be used as a proxy to predict the regional rainfall.However,there appears to be little to be gained from using the predicted EASMI as a proxy for regional rainfall on monthly time scales compared with predicting the rainfall directly.Although interannual variability of the June mean rainfall is affected by synoptic and intraseasonal variations,which may be inherently unpredictable on the seasonal forecasting time scale,the major influence of equatorial Pacific sea surface temperatures from the preceding winter on the June mean rainfall is captured by the model through their influence on the western North Pacific subtropical high.The ability to predict the June mean rainfall in the middle and lower Yangtze River basin at a lead time of up to 4 months suggests the potential for providing early information to contingency planners on the availability of water during the summer season.  相似文献   
6.
A numerical ice-sheet model was run in order to produce reconstructions of the Late Weichselian ice coverage of Franz Josef Land, Russian High Arctic. The model grid covers the archipelago and surrounding shelf, but does not include the whole Barents-Kara region or the extensive ice cover that may have built up there. One experiment, where rates of iceberg calving at the grounded margin were curtailed because of the assumed presence of permanent thick sea ice, yielded a single I.8 km-thick ice dome which covered the entire archipelago and surrounding sea. If, however, iceberg calving were included in the model's environmental input, the extent of the ice sheet would be limited to the periphery of the archipelago. If a large ice sheet existed over Franz Josef Land, the deglaciation of the islands may have been linked to the decay of the adjacent Barents-Kara Sea Ice Sheet, permitting iceberg calving (enhanced by relative sea-level rise) to occur. The introduction of a water-depth-related iceberg calving function at 15 000 yr ago forced an initial rapid rate of ice-sheet decay of 30 000 km3 1000 yr'. However, as the ice sheet thinned, and isostatic rebound began, the calculated rate of iceberg calving was reduced such that ice remained over the archipelago at 8000 yr ago. The model's failure to simulate complete ice-sheet decay by 8000 yr ago is at variance with radiocarbon-dated raised terraces on Franz Josef Land, which indicates the complete deglaciation of the islands at this time.  相似文献   
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The development of the future atmospheric chemical composition is investigated with respect to NO y and O3 by means of the off‐line coupled dynamic‐chemical general circulation model ECHAM3/CHEM. Two time slice experiments have been performed for the years 1992 and 2015, which include changes in sea surface temperatures, greenhouse gas concentrations, emissions of CFCs, NO x and other species, i.e., the 2015 simulation accounts for changes in chemically relevant emissions and for a climate change and its impact on air chemistry. The 2015 simulation clearly shows a global increase in ozone except for large areas of the lower stratosphere, where no significant changes or even decreases in the ozone concentration are found. For a better understanding of the importance of (A) emissions like NO x and CFCs, (B) future changes of air temperature and water vapour concentration, and (C) other dynamical parameters, like precipitation and changes in the circulation, diabatic circulation, stratosphere‐troposphere‐exchange, the simulation of the future atmosphere has been performed stepwise. This method requires a climate‐chemistry model without interactive coupling of chemical species. Model results show that the direct effect of emissions (A) plays a major rôle for the composition of the future atmosphere, but they also clearly show that climate change (B and C) has a significant impact and strongly reduces the NO y and ozone concentration in the lower stratosphere.  相似文献   
9.
Abstract— Fayalitic olivine (Fa54–94) is a ubiquitous component in the matrix of Krymka (LL3.1) as well as in other highly unequilibrated chondrites (ordinary and carbonaceous). In Krymka, the fayalitic olivine has an unusual anisotropic platy morphology that occurs in at least five types of textural settings that can be characterized as: (1) isolated platelets, (2) clusters of platelets, (3) euhedral to subhedral crystals, (4) overgrowths of platelets on forsteritic olivine, and (5) fluffy (porous) aggregates. From transmission electron microscope (TEM) investigation, the direction of elongation of the platy olivine overgrowths on forsteritic olivine substrates is along the c axis and in most cases it corresponds with the c axis of the substrate olivine, which suggests that the fayalitic olivine grew in this unusual morphology and is not a replacement product of preexisting material. The fayalitic olivine in the matrix of Krymka is compositionally similar to olivine with platy morphology in the matrix of some CV3 chondrites and both have similar Fe/Mn ratios, but important morphological differences indicate that their relationship needs to be explored further. Textural and compositional data indicate that the fayalitic olivine in the matrix of Krymka, as well as in some other unequilibrated ordinary chondrites, formed prior to final lithification of the meteorite and probably prior to parent body accretion. We find that formation of the fayalitic olivine by vapor-solid growth provides the best explanation for our observations and data and is the only feasible mechanism for the formation of fayalitic olivine in the matrix of Krymka. We propose that the fayalitic olivine formed by vaporization and recondensation of olivine rich-dust, during a period of enhanced dust/gas ratio in the nebula.  相似文献   
10.
Multivariate outliers in environmental data sets are often caused by atypical measurement error in a singlevariable.From a quality assurance perspective it is important to identify these variables efficiently so thatcorrective actions may be performed.We demonstrate a procedure for using two multivariate tests toidentify which variable‘caused’each outlier.The procedure is tested with simulated data sets that havethe same correlation structure as selected water chemistry variables from a survey of lakes in the WesternUnited States.The success rates are evaluated for three of the variables for sample sizes of 50 and 100,significance levels of 0.01 and 0.05 and various amounts of mean shift.The procedure works best forhighly correlated variables.  相似文献   
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