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Curie-point depth map of Turkey   总被引:3,自引:0,他引:3  
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Maps of shallow depth (down to −250 m) temperature distribution across Canada show large variability, related mainly to surface climatic forcing. Very small changes of temperature with depth in the upper 250 m are related to heat gained by the subsurface due to recent global warming. Temperature data compiled from precise temperature logs in equilibrium wells, and temperature time series from a network of meteorological stations, allow calculation of the available heat energy for heating in the cold period and for cooling in peak warm months. Utilization of this energy resource has the potential for significant CO2 reduction in Canada. The geothermal energy stored in the ground can be used, with the help of heat pumps, for heating, given very low winter temperatures. The amount of potential heat available is vast. In Canada, south of permafrost border, the integrated value of potentially available heat during the heating season down to −50 m is 1.1 E21 J (1100 quads).  相似文献   

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The relationships between diatoms (Bacillariophyceae) in surface sediments of lakes and summer air temperature, pH and total organic carbon concentration (TOC) were explored along a steep climatic gradient in northern Sweden to provide a tool to infer past climate conditions from sediment cores. The study sites are in an area with low human impact and range from boreal forest to alpine tundra. Canonical correspondence analysis (CCA) constrained to mean July air temperature and pH clearly showed that diatom community composition was different between lakes situated in conifer-, mountain birch- and alpine-vegetation zones. As a consequence, diatoms and multivariate ordination methods can be used to infer past changes in treeline position and dominant forest type. Quantitative inference models were developed to estimate mean July air temperature, pH and TOC from sedimentary diatom assemblages using weighted averaging (WA) and weighted averaging partial least squares (WA-PLS) regression. Relationships between diatoms and mean July air temperature were independent of lake-water pH, TOC, alkalinity and maximum depth. The results demonstrated that diatoms in lake sediments can provide useful and independent quantitative information for estimating past changes in mean July air temperature (R2 jack = 0.62, RMSEP = 0.86 °C; R2 and root mean squared error of prediction (RMSEP) based on jack-knifing), pH (R2 jack = 0.61, RMSEP = 0.30) and TOC (R2 jack = 0.49, RMSEP = 1.33 mg l-1). The paper focuses mainly on the relationship between diatom community composition and mean July air temperature, but the relationships to pH and TOC are also discussed.  相似文献   

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藏北羌塘高原双湖地表热源强度及地表水热平衡   总被引:2,自引:0,他引:2  
青藏高原加热及地—气间物质能量交换对我国、东亚乃至全球的天气和气候系统都有着非常重要的作用,受客观条件限制,藏北羌塘高原腹地尚无系统的地—气相互作用过程观测。本文利用中国科学院羌塘双湖极端环境综合观测研究站2011年10月-2012年9月一年的自动气象站观测数据,分析了年内季节和日尺度下双湖地区地面加热场特征,探讨了地表能量平衡及水量平衡特征,结果表明:(1) 双湖地区年内地表热源强度基本为正,年平均热源强度为79.5 W/m2;然而地表热源强度呈现明显的季节和日变化规律,夏季热源强度大于冬季,白天热源强度大于夜间。夏季地表白天为强热源,夜间为弱热源,冬季地表白天为强热源,夜间为冷源。(2) 双湖地区地表能量分配季节变化明显,7、8月份地—气间主要以潜热交换为主,其他月份主要以感热方式进行热量交换,年平均上主要以感热交换为主,年均感热通量和潜热通量分别为55.4 W/m2和24.1 W/m2,波文比为2.3。(3) 双湖地区降水和蒸发皆主要集中在6-9月,年降雨量为332 mm,年蒸发量为312.9 mm,年水量差为19.1 mm,地表水量存在不平衡现象。(4) 双湖地区地表蒸发力很强,年潜在蒸发为1888.2 mm,年均湿润指数为0.17,属典型半干旱气候特征。  相似文献   

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This paper concentrates on the 1% richest households in the UK in a comparison with the other four large Western European countries: Germany, France, Italy and Spain. In the European context the UK is an outlier of extreme inequality. Individual level tax data has shown this previously, but earlier research did not make comparisons at the household level, or in as much detail as it is possible to show now given new survey findings.In the UK the geographical separation of the 1% from mainstream society increased in recent decades as their incomes levels diverged widely from that of the mainstream. There is now acute socioeconomic polarization in the UK as compared to the other large European states because of the current extent of income and wealth inequalities in the UK. Not so long ago members of the best-off 1% within the UK were far more evenly spread across both the space and society of the UK than they are today.The UK is now the European country most similar to the USA in terms of income inequalities. Along with Sweden it was least like the USA in the 1960s. This paper concludes by considering what might happen (if current trends continue) to standards of living in general, social spatial polarization, fear and mistrust. Growing income inequalities increase wealth inequalities. Some info-graphics aimed at showing the contemporary extent of wealth inequalities in the UK and USA are presented in conclusion and for use in teaching  相似文献   

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Due to the impact of climate change and human activities, the upper and middle reaches of the Tao’er River have become an ecologically sensitive area in Northeast China. It is important to evaluate the contributions of climate change and human activities to water suitability in the Tao’er River area. From the perspective of water and heat balance, the water suitability index (cr) was used to analyze the water suitability of the upper and middle reaches of the river. The nonparametric Mann-Kendall, moving t-test and cumulative anomaly methods were used to detect abrupt changes in Taonan station runoff from 1961 to 2012. Three inflexion years were detected. Thus, the entire time period was divided into four periods: 1961-1974, 1975-1983, 1984-1998, and 1999-2012. In order to estimate the impacts of climate change and human activities on runoff, the slope change ratio of cumulative quantity (SCRCQ) was adopted. Finally, the contribution of climate change and human activity to cr was transformed from the contribution of climate change and human activity to runoff by the sensitivity coefficient method and SCRCQ method. The results showed that the water suitability index (cr) had a decreasing trend 1961-2012. Factors influencing cr, such as net radiation and runoff, also exhibited a decreasing trend, while precipitation exhibited an increasing trend over the past 52 years. The trends of cr, net radiation and runoff were obvious, which passed the Mann-kendall test of significance at α=0.05. Human activities were the main factors that affected runoff, although the degree of impact was different at different times. During the past 52 years, the biggest contributor to the change in cr was precipitation.  相似文献   

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Basement depth in the Arabian plate beneath eastern Syria is found to be much deeper than previously supposed. Deep-seated faulting in the Euphrates fault system is also documented. Data from a detailed 300 km long reversed refraction profile, with offsets up to 54 km, are analysed and interpreted, yielding a velocity model for the upper 9 km of continental crust. The interpretation integrates the refraction data with seismic-reflection profiles, well logs and potential field data, such that the results are consistent with all available information. A model of sedimentary thicknesses and seismic velocities throughout the region is established. Basement depth on the north side of the Euphrates is interpreted to be around 6 km, whilst south of the Euphrates basement depth is at least 8.5 km. Consequently, the potentially hydrocarbon-rich pre-Mesozoic section is shown, in places, to be at least 7 km thick. The dramatic difference in basement depth on adjacent sides of the Euphrates graben system may suggest that the Euphrates system is a suture/shear zone, possibly inherited from Late Proterozoic accretion of the Arabian plate. Gravity modelling across the southeast Euphrates system tends to support this hypothesis. Incorporation of previous results allows us to establish the first-order trends in basement depth throughout Syria  相似文献   

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