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431.
432.
The survey for the HEIFE(Atmosphere-Land Surface Processes Experiment at Heihe RiverBasin,Western China)is given in the paper.The following basic subjects for land-surface process-es in arid areas are studied:(1)the general characteristics of the energy budget on ground surfacein arid areas;(2)the parameterization of the land surface processes;(3)the interaction betweenoasis and its desert circumstances,a special phenomenon in arid areas.The analysis shows that thesensible heat flux in the surface energy budget is in the majority,and the latent heat flux may beneglected.The influence of atmospheric stratification stability on the turbulent transfer of energyand substance must be considered in parameterization of land surface processes in arid areas.The“cold island effect”phenomenon in oasis and the“humidity inversion”phenomenon in desert nearoasis are the result of the interaction between them.The results would improve the understandingof land surface processes in arid areas. 相似文献
433.
Impacts of the Kuwait Oil Fires on the Mount Qomolangma Region 总被引:6,自引:0,他引:6
Mt. Qomolangma (also known as Mt. Everest), the world’s highest mountain, is situated over the world’s highest plateau, the Tibetan Plateau. Because of its height and because of its distance from industrialized areas, the environmental state of the Mt. Qomolangma region can normally be considered “undisturbed”. It is interesting to investigate how this “undisturbed” state has been changing with time and whether it has been influenced by large environmentally disruptive events such as the Kuwait oil fires of 1990 and 1991 (Small, 1991). In order to do this, riv-er water samples were collected from the Rongpu River at Rongpu Temple Station in the summers of 1992 and 1993, as was done in 1975, and aerosol samples were collected in the summer of 1992 at the same station as was done in 1980. River water samples were analyzed using atomic absorption spectroscopy (AAS) at the Chinese Academy of Sciences. Aerosol samples were analyzed using proton-induced x-ray emission (PIXE) at the University of Fudan in Shanghai. The results show that the concentrations of chemical species in the river water at Rongpu Temple Station were much higher in the summer of 1992 than they were in 1975 and 1993, and the concentrations of atmospheric chemical species were much higher in 1992 than they were in 1980. The environment of the north slope of Mt. Qomolangma was therefore heavily polluted before and/or during the summer of 1992, possibly due to the Kuwait oil fires in 1990 and 1991. 相似文献
434.
Gao Shiyu Zhang Lianqiang Tang Tianming and Fu ChanghongInstitute of Geophysics SSB Beijing China 《中国地震研究》1996,(2)
By analyzing seismograms of short period records at the Beijing SeismoJogicaJ Observatory, the present paper investigates the amplitude ratio of seismic phases. The results indicate that the amplitude ratio of Sn/Lg is correlated with the lithosphere structure, the thermal state, and strong earthquake occurrence in the region the seismic rays pass through. The significance of such a correlation in the study on the genesis and prediction of strong earthquakes is discussed. 相似文献
435.
Wang Xiaoqing Gao MengtanCenter for Analysis Prediction SSB Beijing China Institute of Geophysics SSB Beijing China 《中国地震研究》1996,(2)
This paper offers an approach to the relative confidence level of medium- and long-term earthquake prediction methods by use of the analytical hierarchy process (AHP). We construct the criterion judgment matrices according to the results of an expert questionnaire known as the Delphi scheme. From the matrices we can obtain a scale for the relative preference or priority weight of each factor. The quantitative weights might be applied to make synthetic prediction of earthquake risk areas in the northern part of the North China seismic region. 相似文献
436.
潜在震源区内部空间非均匀分布地震区划方法在攀西地区和晋中南地区的应用 总被引:2,自引:1,他引:2
本文依据潜在震源区内部地震非均匀分布模型研究了攀西地区和晋中南地区地震区划问题。研究结果表明,一般使用的均匀分布模型会低估地震危险性结果,导致高烈度分区的面积缩小。本文讨论了不同的确定非均匀分布概率的方法对地震区划结果的影响。 相似文献
437.
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439.
喜马拉雅构造带于新生代时期经历了两代受力条件截然不同的形变。早期造山挤压形变与造山后的引张形变、青藏高原和高喜马拉雅的大幅度抬升。大致低喜马拉雅范围即青藏高原南缘,现今构造活动与青藏高原和高喜马拉雅块断抬升相辅相成。流行的板块聚合动力学模式,即使早新生代发生过,晚新生代以来已经灯熄。东亚大陆现代形变与地震活动的驱动力不可能源于青藏高原南缘被动挤压,而是取决于与高原隆起相关的深部主动动力学过程 相似文献
440.
旨地探索研究地震预报而开展的北京地区地磁观测,在震磁前兆研究与地震预测试验方面都获得了可喜的进展,本文分析了1990-1995年北京及其西部地区的地磁观测资料,研究了地磁异常信息,预测了地震活动趋势,提出了今后应加强监测与研究的区域。 相似文献