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991.
 The Elbe region is representative of humid to semi-humid landscapes in Central Europe, where water availability during the summer season is the limiting factor for plant growth and crop yields, especially in the loess areas with high crop productivity having annual precipitation lower than 500 mm. This paper summarizes the results of the first phase of the GLOWA (GLObal WAter)-Elbe project and tries to assess the reliability of water supply in the German part of the Elbe river basin for the next 50 years, a time scale relevant for the implementation of water and land use management plans. One focus of the study was developing scenarios which are consistent with climate and land use changes considering possible uncertainties. The concluding result of the study is that nature and communities in parts of Central Europe will have to deal with considerably lower water resources under scenario conditions.  相似文献   
992.
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994.
Atmospheric stability conditions over the water surface can affect the evaporative and convective heat fluxes from the water surface. Atmospheric instability occurred 72.5% of the time and resulted in 44.7 and 89.2% increases in the average and maximum estimated evaporation, respectively, when compared to the neutral condition for a small shallow lake (Binaba) in Ghana. The proposed approach is based on the bulk-aerodynamic transfer method and the Monin-Obukhov similarity theory (MOST) using standard meteorological parameters measured over the surrounding land. For water surface temperature, a crucial parameter in heat flux estimation from water surfaces, an applicable method is proposed. This method was used to compute heat fluxes and compare them with observed heat fluxes. The heat flux model was validated using sensible heat fluxes measured with a 3-D sonic anemometer. The results show that an unstable atmospheric condition has a significant effect in enhancing evaporation alongside the sensible heat flux from water surfaces.  相似文献   
995.
Tritium is one of the most important environmental tracers in isotope hydrology for understanding the dynamics of groundwater and connected surface water and has been used in a wide range of applications at different scales. A key requirement for using tritium as a tracer is the knowledge of its spatial and temporal distribution in different water types. As a fundamental input, quantity long-term time series of tritium in precipitation are of particular importance. In this paper, the authors present an overview of tritium data sets of the Federal Institute of Hydrology (BfG), the Helmholtz Zentrum München (HMGU) and the German Weather Service (DWD). Since the 1970s, all three institutions have monitored the tritium concentration at 53 surface water and 37 precipitation stations on a monthly basis. The primary purpose of the data set was to provide baseline information for different water types all over Germany as an integral part of the German radiation protection monitoring system. Additionally, as geochemically inert tracer, tritium provides a unique tool to different user groups in a wide range of research questions and applications.  相似文献   
996.

Rapid and accurate identification of potential structural deficiencies is a crucial task in evaluating seismic vulnerability of large building inventories in a region. In the case of multi-story structures, abrupt vertical variations of story stiffness are known to significantly increase the likelihood of collapse during moderate or severe earthquakes. Identifying and retrofitting buildings with such irregularities—generally termed as soft-story buildings—is, therefore, vital in earthquake preparedness and loss mitigation efforts. Soft-story building identification through conventional means is a labor-intensive and time-consuming process. In this study, an automated procedure was devised based on deep learning techniques for identifying soft-story buildings from street-view images at a regional scale. A database containing a large number of building images and a semi-automated image labeling approach that effectively annotates new database entries was developed for developing the deep learning model. Extensive computational experiments were carried out to examine the effectiveness of the proposed procedure, and to gain insights into automated soft-story building identification.

  相似文献   
997.
The majority of original seismograms recorded at the very beginning of instrumental seismology (the early 1900s) did not survive till present. However, a number of books, bulletins, and catalogs were published including the seismogram reproductions of some, particularly interesting earthquakes. In case these reproductions contain the time and amplitude scales, they can be successfully analyzed the same way as the original records. Information about the Atushi (Kashgar) earthquake, which occurred on August 22, 1902, is very limited. We could not find any original seismograms for this earthquake, but 12 seismograms from 6 seismic stations were printed as example records in different books. These data in combination with macroseismic observations and different bulletins information published for this earthquake were used to determine the source parameters of the earthquake. The earthquake epicenter was relocated at 39.87° N and 76.42° E with the hypocenter depth of about 18 km. We could further determine magnitudes m B = 7.7 ± 0.3, M S = 7.8 ± 0.4, M W = 7.7 ± 0.3 and the focal mechanism of the earthquake with strike/dip/rake ? 260°± 20/30°± 10/90°± 10. This study confirms that the earthquake likely had a smaller magnitude than previously reported (M8.3). The focal mechanism indicates dominant thrust faulting, which is in a good agreement with presumably responsible Tuotegongbaizi-Aerpaleike northward dipping thrust fault kinematic, described in previous studies.  相似文献   
998.
ABSTRACT

Much has changed since the first mapping of single-sex couples and families from the 2006 Australian census. An increasing willingness to allow their identification in the census has accompanied increasing public acceptance of same-sex couples culminating in significant support for legalising same-sex marriage in a 2017 national survey. Technological advances permit complex cross-tabulations of Australian census data and more detailed characterisations of same-sex couples. New geographies differentiate between male and female couples with children, showing same-sex couples are not just a feature of some inner-city areas, though these remain important, but also of suburban, regional and some rural areas. Drawing on the 2016 census, contemporary geographies of same-sex couples with and without children in Australia and changes over the past decade in Sydney are analysed at a time of increased interest in this demographic.  相似文献   
999.
Projectile–target interactions as a result of a large bolide impact are important issues, as abundant extraterrestrial material has been delivered to the Earth throughout its history. Here, we report results of shock‐recovery experiments with a magnetite‐quartz target rock positioned in an ARMCO iron container. Petrography, synchrotron‐assisted X‐ray powder diffraction, and micro‐chemical analysis confirm the appearance of wüstite, fayalite, and iron in targets subjected to 30 GPa. The newly formed mineral phases occur along shock veins and melt pockets within the magnetite‐quartz aggregates, as well as along intergranular fractures. We suggest that iron melt formed locally at the contact between ARMCO container and target, and intruded the sample causing melt corrosion at the rims of intensely fractured magnetite and quartz. The strongly reducing iron melt, in the form of μm‐sized droplets, caused mainly a diffusion rim of wüstite with minor melt corrosion around magnetite. In contact with quartz, iron reacted to form an iron‐enriched silicate melt, from which fayalite crystallized rapidly as dendritic grains. The temperatures required for these transformations are estimated between 1200 and 1600 °C, indicating extreme local temperature spikes during the 30 GPa shock pressure experiments.  相似文献   
1000.
本文比较了基于AMSR-E被动微波数据的3种土壤冻融判别算法在青藏高原相关地区的分类精度。3种算法分别是:双指标算法、决策树算法、判别函数算法。本文选取了来自青藏高原那曲、玛曲、阿里3个地区土壤温湿度观测网的地表温度数据,并结合AMSR-E被动亮温数据,对上述算法在以上地区的分类精度分别进行了比较评价。结果表明:不论是白天还是夜间,相较于干旱区微波信号来自深层土壤的难以准确探测,在青藏高原半湿润半干旱区算法可取得相对较好的判别准确率;双指标算法相较于其他2种算法,在观测区具有较高的分类精度,且夜间分类精度高于白天;实测数据存在资料代表性不普遍即网格所包含站点信息量不够的问题,这也是后续工作中提高分类精度值得关注的着手点。  相似文献   
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