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Model calculation of air-sea heat fluxes over ocean area near china with GEOS DAS system

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Acta Oceanologica Sinica 1999年第3期18卷 401-411页

作者：周明煜钱粉兰 Natl. Mar. Environ. Forecast. center State Oceanic Administration Beijing 100081 China

The sensible and latent heat fluxes over the ocean area near china were calculated and analyzed by usingthe Goddard Earth Observing System (GEOS) - four-dimensional Data Assimilation System (DAS). The calculated results showed that the sensible heat flux had its large value in winter and autumn , small value in spring and summer overthe ocean area near china. In winter, the sensible heat flux increased distinctly with latitude, and its isolines were verycrowded. Over the ocean area east of Taiwan Province and south of Japan, the direction of isoline was from southwestto northeast. In the South china Sea the sensible heat flux was lower than that of surrounding ocean areas,and its isoline was distributed into a type of an inverted trough. In autumn and winter, the maximum center of latent heat flux appeared over the ocean area northeast of Taiwan Province and south and southeast of Japan, meanwhile, the isoline wasin the direction of southwest to northeast. In spring and summer, the latent heat flux had minimum value in the Huanghai Sea. At the same time, the maximum value center of latent heat flux appeared over the ocean area south of Japan inspring.

关键词： GEOS DAS system the ocean area near china sensible heat flux latent heat flux

Application of the moist vorticity vector in the analysis of a heavy rainfall event in North china

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Progress in Natural Science:Materials International 2007年第12期17卷 1457-1465页

作者： Zhao Yu1,2.3, Wang Jianguo4 and Xue Deqiang2.1. Laboratory of Cloud-Precipitation Physics and Severe Storms, Institute of Atmospheric Physics, Chinese Academy of Sciences, beijing 10002., china 2. Shandong Provincial {2. Observatory, Jinan 2.0031, china 3. Graduate University of Chinese Academy of Sciences, beijing 100039, china 4. Shandong Provincial {2. Bureau, Jinan 2.0031, china) Laboratory of Cloud-Precipitation Physics and Severe Storms Institute of Atmospheric Physics Chinese Academy of Sciences Beijing 100029 China Shandong Provincial meteorological Observatory Jinan 250031 China Graduate University of Chinese Academy of Sciences Beijing 100039 China Shandong Provincial meteorological Bureau Jinan 250031 China

The moist vorticity vector (MVV), defined as (ζa×▽qv)/ρ introduced by Gao et al. is used to study a heavy rainfall event in North china. The MVV has zonal, meridional and vertical components in a three-dimensional framework. Analysis of domain-mean and mass-integrated quantities shows that the variation of the vertical component of the MVV closely follows the variation of the cloud hydrometeors, with a linear correlation coefficient of 0.95, indicating that the vertical component of the MVV is strongly associated with midlatitude convection. Further analysis shows that the vertical component of the MVV reflects the interaction between the horizontal vorticity and the horizontal specific humidity gradient, which can associate dynamic and thermodynamic processes with cloud microphysical processes. Thus, this study can help to understand how the interaction between circulations and clouds aids the development of convection, and the MVV can be used to trace the development and evolution of heavy rainfall.

关键词： moist vorticity vector heavy rainfall modeling study.

The tectonic settings and seismogenic tectonics of the M5.7 Jiujiang earthquake in 2.05,Jiangxi Province,china

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Science china Earth Sciences 2008年第5期51卷 640-653页

作者： LI ChuanYou1, ZENG XinFu2.& ZHANG JianXi3 1 Institute of Geology, china Earthquake administration, {2. 10002., china 2.Jiangxi Earthquake administration, Nanchang 330039, china 3 {2. Earthquake administration, {2. 100080, china 1. Institute of Geology China Earthquake Administration Beijing 100029 China 2. Jiangxi Earthquake administration Nanchang 330039 China 3. beijing Earthquake administration Beijing 100080 China

The M5.7 Jiujiang earthquake in 2.05 was a mid-strong one, stronger than expected to occur in the region. This paper discusses the neo-tectonic settings of this earthquake, and it is thought that the earthquake region is located in the transitional belt, a potential area inducing weak to moderately strong earthquakes, between two large different tectonic units. The results of the reconnaissance work and on-the-spot investigation after earthquake indicate that the occurrence of the M5.7 Jiujiang earth- quake is closely related with the NE-trending fault on the western margin of Ruichang Basin. From its controlling to the landforms and Quaternary depositions, geological profiles, ESR dating, etc., the ac- tivity of the Dingjiashan-Langjunshan fault bounding the basin is discussed. It suggests that this fault displays an active one in Middle Pleistocene by the outcrop. Based on the activity of the fault, and the direction and location of the ground fissures, the isoseismal lines and the nodal plane of the focal mechanism solution, it is inferred that the Dingjiashan-Langjunshan fault is the seismogenic tectonics of the M5.7 Jiujiang earthquake, and the intersection point between this fault and the active NW ones is the possible origin of location of this earthquake. Our study shows that this earthquake is not an event exceeding expectation, and that the active and invisible characteristics of the causative fault are typical in the eastern area of china.

关键词： Jiujiang earthquake tectonic settings Dingjiashan-Langjunshan fault activity seismogenic tectonics

Wave decomposition phenomenon and spectrum evolution over submerged bars

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Acta Oceanologica Sinica 2009年第3期28卷 82-92页

作者： LI Benxia YU Xiping national Marine Environmental Forecasting center State Oceanic Administration Beijing 100081China Department of Hydraulic Engineering Tsinghua University Beijing 100084 China

Wave decomposition phenomenon and spectrum evolution over submerged bars are investigated by a previously developed numerical model. First, the computed free surface displacements of regular waves at various locations are compared with the available experimental data to confirm the validity of the numerical model, and satisfactory agreements are obtained. In addition, variations of decomposition characteristics with incident wave parameters and the change of energy spectrum for regular waves are also studied. Then the spectrum evolution of irregular waves over submerged bars, as well as the influence of incident peak wave period and the steepness of the front slope of the bar on spectrum evolution, is investigated. Wave decomposition and spectral shape are found to be significantly influenced by the incident wave conditions. When the upslope of the bar becomes 1：2. the length of the slope becomes shorter and will not benefit the generation of high frequency energy, so spectrum evolution is not significant.

关键词： wave decomposition spectrum evolution nonlinear waves irregular waves submerged bars

Interannual variation of annual precipitation and urban effect on precipitation in the beijing region

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Progress in Natural Science:Materials International 2007年第9期17卷 1042-1050页

作者： Yu Shuqiu(State Key Laboratory on Severe Weather,Chinese Academy of meteorological Sciences,beijing {2.,china) State Key Laboratory on Severe Weather Chinese Academy of Meteorological Sciences Beijing 100081， China

The large scale character of the interannual variation of precipitation and the urban effect on local annual precipitation anomaly are investigated in this paper based on the 1960-2.00 annual precipitation observations at 2. stations in the beijing *** results show that:the annual precipitation in the beijing region possesses the large scale variation character with the linear trend of-1.197/10 yr,which corresponds to a total reduction of 2..82.mm in annual precipitation in the 41 years;the local annual precipitation anomalies(percent of the normal 1960-2.00)show a positive {2. near the urban area,*** precipitation island(UPI),whose intensity increases with the linear trend of 0.662.%/10 yr,opposite to the interannual trend of large scale precipitation over the beijing region;changes in the UPI are also associated with the intensity of synoptic processes of precipitation,and when the synoptic processes are strong(wet years),the intensity of UPI strengthens,while the synoptic processes are weak(dry years),and the UPI disappears in the beijing region.

关键词： urban precipitation island effect interannual climate variation precipitation beijing atmospheric science

Evolution of terraces Ⅰ–Ⅲ along the Anning River, western Sichuan, based on pollen records and terrace structure

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Science china Earth Sciences 2011年第1期54卷 127-135页

作者： CHENG JianWu1,2.1 Institute of Geology, china Earthquake administration, {2. 100039, china 2.Earthquake administration of Gansu Province, Lanzhou 730000, china Institute of Geology China Earthquake Administration Beijing China Earthquake administration of Gansu Province Lanzhou China

This study reconstructs the long-term evolution of river terraces over large spatial scales along the Anning River, western Sichuan, and identifies external factors controlling terrace formation. Pollen record analysis and terrace structure indicate that formation of the middle section of terraces I-III resulted from the interaction of changing climates and uplift of the margins of the Qinghai-Tibet Plateau. The relative influence of climate and uplift in terrace formation changes in different periods. The terraces reveal multiple, gradual uplift events on the eastern Qinghai-Tibet Plateau, which is of great significance for determining uplift mechanisms across the entire plateau.

关键词： Anning River in western Sichuan terrace formation pollen paleoclimate

Applied research of landscape ecology in desertification monitoring and assessment

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Journal of Environmental Sciences 2000年第3期12卷 349-354页

作者： LI Feng, SUN Si heng (Academy of Forest Inventory and Planning/china national Desertification Monitoring {2., State Forestry administration, beijing 100714, china) Academy of Forest Inventory and Planning/china national Dese 北京 1 0 0 71 4

A preliminary research on landscape ecology in desertification monitoring and assessment was reported. Also, this paper laid stress on the study of landscape diversity, dominance, evenness and Markov Matrix model and their respective landscape ecological meanings in the desertification monitoring and assessment. Concurrently, it took Shazhuyu Experimental Area, Qinghai Province as a specific case study.

关键词： landscape ecology desertification monitoring and assessment Shazhuyu Experimental Area

umerical tests of efficiency of the retrospective time integration scheme in the self-memory model

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Progress in Natural Science:Materials International 2004年第9期 89-92页

作者： GU Xiangqian 1*, YOU Xingtian 2. ZHU He 2.and CAO Hongxing 1(1. Chinese Academy of meteorological Sciences, beijing 100081,{2. 2. Training center of china meteorological administration, beijing 100081,{2.)

A set of numerical tests was carried out to compare the retrospective time integral scheme in a self memory model, whose dynamic kernel is the barotropical quasi geostrophic model, with the ordinary centered difference scheme in the barotropical quasi geostrophic model. The Rossby Haurwitz wave function was taken as the initial fields for both schemes. The results show that in comparison with the ordinary centered difference scheme, the retrospective time integral scheme reduces by 2.orders of magnitude the forecast error, and the forecast error increases very little with lengthening of the time step. Therefore, the retrospective time integral scheme has advantages of improving the forecast accuracy, extending the predictable duration and reducing the computation amount.

关键词： numerical tests self-memory model retrospective time integral scheme.

An integrative estimation model of summer rainfall-band patterns in china

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Progress in Natural Science:Materials International 2007年第3期17卷 280-288页

作者： WEI Fengying (State Key Laboratory of Severe Weather, Chinese Academy of meteorological Sciences, beijing 100081,{2.) State Key Laboratory of Severe Weather Chinese Academy of Meteorological Sciences Beijing 100081 China

Three variation indices are defined to objectively and quantitatively represent fluctuations of three rainfall-band patterns in summers in china for the period from 1951 to 2.05, and the variation features of these indices are analyzed on both of interdecadal and interannual scales. A new method is proposed to establish an integrative estimation model based on the analysis of rainfall-band indices, and the model is applied to air, ocean factors to estimate their roles on variations of three rainfall-band patterns on different time-scales. The tests of estimation effects show that the fluctuations of three rainfall-band patterns are composed of variations on both significant inter-decadal and interannual scales, of which the interannual variation is mainly influenced by the Elnino/Lanina events, the East Asia monsoon and the ridge locations of subtropical high pressures in western pacific, while the interdecadal variation is mainly controlled by the Pacific decadal oscillation and interdecadal oscillations of the Arctic oscillation, ENSO, Nino3 sea surface temperature and summer monsoon. The estimated results from the integrative estimation model of rainfall-band patterns suggest that the way of estimation first according to each time scale of both the interdecadal and interannual scales, then estimating with an integration, which is proposed in this paper, has an obvious improvement on that without separation of time scales.

关键词： rainfall-band pattern interannual variation interdecadal variation integration estimation model.