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451.
Using available wind wave spectra data, we consider the applicability conditions of the tangent plane (Kirchhoff) method and the small perturbations and diffusion (Rayleigh) method to construct microwave diagrams of sea surface scattering (quasi-mirror forward scattering). We take into account the peculiarities of Earth sensing from orbit, the closeness of viewing of a mirror point to the Brewster angle, and the possibility of simultaneous formation of wide-capture radar images for the coaxial and collinear polarization components of a reflected signal. It is concluded that, taking into account the approximations made, it is possible to creat panorama small- and mesoscale images of the field of wind wave slopes for a coverage area on the order of 2000 km. Then, based on earlier engineering design studies, we present three possible modifications of “tandem” space radar designed to efficiently solve certain oceanological and applied problems. 相似文献
452.
The impact of the subtropical high (STH) on precipitation was investigated on a daily timescale using matched NCEP and the Global Precipitation Climatology Project (GPCP) datasets. Comparison of the conditional probability (intensity) of precipitation under STH conditions with that under non-STH conditions suggests that the presence of the STH conditions has a limited impact on local precipitation. In the West Pacific Subtropical High (WPSH) and the North Atlantic Subtropical High (NASH), precipitation was only 30% lower under STH conditions than under non-STH conditions. The STH conditions had somewhat more impact on precipitation intensity, but it was still 50% less than the intensity under non-STH conditions (mean of roughly 5 mm d^-1). Precipitation under STH conditions was found to be highly correlated with vertical motion. Active updrafts occurring even under STH conditions are essential for frequent occurrences and moderate intensities of precipitation. 相似文献
453.
E. Sh. Elizbarashvili O. Sh. Varazanashvili N. S. Tsereteli M. E. Elizbarashvili M. N. Kaishauri 《Russian Meteorology and Hydrology》2012,37(8):567-569
The peculiarities of wire icing in mountain areas of Georgia are investigated using the observational data of 14 meteorological stations of Georgia. Determined are the maximum frequency and the maximum mass of glaze-ice deposits, as well as the frequency of deposits of different mass and thickness. Considered are the effects of orography and meteorological conditions on the wire icing processes. 相似文献
454.
N. A. Imamverdiyev V. M. Baba-zade A. E. Roman’ko Sh. F. Abdullaeva M. Ya. Gasangulieva G. D. Babaeva A. A. Veliev 《Geotectonics》2017,51(5):489-498
The paper considers the role of the lithospheric mantle and asthenosphere during the Late Cenozoic collision volcanism of the Lesser Caucasus. The results of petrogeochemical studies show that the products of volcanism of the West Volcanic Zone of Armenia and the calc-alkaline andesite–dacite–rhyodacite complex of the Neogene Kelbadzhar and Karabakh plateaus were formed from an enriched source in a suprasubduction setting. Late Pliocene–Quaternary moderately alkaline and alkaline volcanic rocks of the Lesser Caucasus differ in petrogeochemistry from suprasubduction volcanic rocks. In trace element contents and patterns, they are similar to rocks formed from an enriched mantle source. Comparative analysis of the geological and geophysical data suggests the model of lithospheric slab break-off of the thickened lithosphere as the triggering mechanism for Late Cenozoic magmatism of the Lesser Caucasus. 相似文献
455.
山东地区寒武系-奥陶系界线以往是以三叶虫和角石生物带为依据来确定,由于在界线上下几十米难以获得这类可供鉴定的大化石,这一重要年代地层界线实际上就划在三山子组b段之底。在长清区崮山镇范庄剖面上该界线确定在炒米店组之顶界,因而山东炒米店组被定义为"上寒武统最上部的一个岩石地层单位"。近年来,在长清张夏—崮山地区、青州尧王山地区和莱芜黄羊山地区,根据牙形石"Cordylodus lindstromi"准确确定的寒武系-奥陶系界线均位于炒米店组内部,分别距炒米店组顶9.05m、58.10m和4.00m。根据上述成果和岩石地层单位命名原则,炒米店组应定义为跨寒武纪与奥陶纪的岩石地层单位。 相似文献
456.
457.
基于四川省1980—2017年主要气象要素观测资料,运用ArcGIS空间分析法,分别探讨了气温、降水量和极端气候指数的年际空间变化特征;同时建立极端气候指标体系,结合熵权法、模糊综合评价法开展综合极端气候指数区划,最终完成1980—2017年四川省气候变化综合区划。研究表明:1980—2017年四川省极端气候事件的发生率呈上升趋势,从区域分布上大致表现为东高西低;根据四川省气温和降水量变化速率区划、综合极端气候指数区划,将四川省划分为6个气候变化区,其中,川东北地区综合气候变化速率最快。 相似文献
458.