吐鲁番2001年4月7～8日特强沙尘暴天气分析     

张新庆  吴新玉  张慧琴 《干旱气象》2002,20(4):4-7

对吐鲁番2001年4月7～8日出现的特强沙尘暴天气进行了分析,指出强锋区、地面冷锋是强沙尘暴形成的大尺度天气背景,高空急流和槽前正涡度平流提供了动力条件,低层强辐合上升运动和大气热力不稳定激发了沙尘暴的形成,沙化的地表是形成这场沙尘暴的重要条件。  相似文献   

中国红土与自然地带变迁   总被引：19，自引：1，他引：18  

黄镇国  张伟强  陈俊鸿 《地理学报》1999,54(3):193-203

我国第四纪冷期气候及自然地带变迁的研究较多,本文则专论暖期,根据棕红色土,红土,强风化红土网纹红土的时空分布,结合其它环境标志,论述亚热带北部,亚热带南部,热带这３个自然地带在上新世以来的４个暖期的配置,推断华北,长江中下游,华中,华南这４个区域的暖期气候变迁及其变幅。  相似文献   

2018年台风“摩羯”和“温比亚”路径的影响因子分析     

李瑞芬  袁月  郭卫华  李一伟 《气象科技》2021,49(3):427-436

利用中国气象局(CMA)提供的热带气旋最佳路径资料和欧洲中心(ECMWF)提供的ERA interim再分析资料,对2018年两个北上影响山东的台风"摩羯"和"温比亚"路径差异的原因进行分析发现:"摩羯"和"温比亚"台风路径的差异主要与周围天气系统分布差异有关,两台风均先后受到副热带高压和大陆高压的影响,"温比亚"还受高空槽的影响,使其转向角度较大,而台风与高压系统相互作用形成的引导气流是影响这两个台风路径的主要因素。"摩羯"和"温比亚"的最佳引导气流均位于台风中心5个纬度半径内,不同阶段所受引导气流的高度存在差异,台风登陆前中低层引导气流对台风移向的指示作用均优于高层,登陆后转向前纬向引导气流均优于经向,但稳定性稍差,转向后除"温比亚"经向引导气流相关较差外均整层相关较好,中高层略优于低层,且高层风(300～200hPa)可以提前12h预报台风转向。此外,台风总是向着台风附近的正涡度平流方向移动,正涡度平流越强,台风移动越快。  相似文献   

Effects　on　Asian　Monsoon　of　Gigantic　Qinghai－Xizang　Plateau　and　Western　Pacific　Warm　Pool     

Zhu Qiangen  Hu Jianglin 《大气科学进展》1995,12(3):351-360

朱乾根，胡江林ＥｆｆｅｃｔｓｏｎＡｓｉａｎＭｏｎｓｏｏｎｏｆＧｉｇａｎｔｉｃＱｉｎｇｈａｉ－ＸｉｚａｎｇＰｌａｔｅａｕａｎｄＷｅｓｔｅｒｎＰａｃｉｆｉｃＷａｒｍＰｏｏｌ￥ＺｈｕＱｉａｎｇｅｎａｎｄＨｕＪｉａｎｇｌｉｎ（ＮａｎｊｉｎｇＩｎｓｔｉｔｕｔｅ...  相似文献   

热带气旋逆时针打转物理机制的研究   总被引：1，自引：2，他引：1  

田永祥 《南京气象学院学报》1995,18(3):361-367

应用一个无基本气流的准地转斜压模式数值模拟热带气旋逆时针打转运动。分析结果表明：对称气流对非对称涡度的平流引起非对称流场中的小尺度涡旋和通风气流逆时针旋转；旋转的通风气流引导热带气旋作逆时针打转运动。  相似文献   

Sensitivity of the tropical nonlinear stationary Kelvin and Rossby waves to the vertical structure of heating     

R. Krishnan  S. V. Kasture 《Journal of Earth System Science》1995,104(4):579-606

Idealized experiments using linear (LM) and nonlinear (NM) multilevel global spectral models have been carried out to investigate and understand the impact of nonlinearities on the stationary wave response in the tropical atmosphere and its sensitivity to the vertical profile of heating. It is found that nonlinearities exert a dominant influence on the low-latitude stationary Kelvin and Rossby waves particularly in the vicinity of the forcing region. Our study shows that nonlinear effects on the upper tropospheric response produce prominent eastward displacement of the anticyclonic vorticity and horizontal shifts of the maximum equilibrium divergence relative to the prescribed heating. These changes due to nonlinear terms are found to be quite sensitive to the vertical structure of diabatic heating. The strongest nonlinear effects are found to occur when the vertical level under consideration is strongly forced from below. Detailed vorticity budget calculations indicate that stronger nonlinear contributions from stretching and horizontal advection of relative vorticity favour the generation of upper tropospheric anticyclonic circulation and its eastward displacement. Larger vertical advection and twisting terms appear to oppose the generation of upper tropospheric anticyclonic vorticity. It is found that the nonlinear terms which affect the vorticity generation in the upper levels are crucially controlled by the vertical profile of heating. The mid-tropospheric response due to deep convective heating in the NM is characterized by anomalous equatorial westerlies in the low-latitude Rossby regime and exhibits prominent ageostrophic motions. Such nonlinear effects appear probably because of a vertical shift of the low level circulation anomalies in the NM. In the case of shallow convective heating the occurrence of anomalous zonal flows and ageostrophic motions in the low latitude regions of the NM takes place near the level of the maximum heating. Our study shows that large heating amplitudes and small vertical gradient of heating at a given vertical level together favour generation of anomalous zonal flows and ageostrophic motions in the near equatorial regions. These anomalous basic flows in the low-latitudes have implications on the propagation of transients from the tropics to midlatitudes. Non-linear effects on the lower tropospheric stationary waves are prominently seen in the case of strong low level heating which produces a large strengthening of the lower tropospheric cyclonic anomalies that exhibit distinct eastward shifts in the NM relative to the LM.  相似文献   

从1999年叶尔羌河和克孜河洪水看新疆河流水情变化趋势   总被引：3，自引：1，他引：3  

何慧 《沙漠与绿洲气象(新疆气象)》2001,24(6):18-20

1999年南疆西部的叶尔羌河发生了冰川湖大洪水，克孜河暴发了暴雨泥石流堵塞的特大溃坝洪水，给喀什地区造成很大灾害；同时随着全球气候变暖，新疆的暴雨洪水和冰川湖洪水以及融水与暴雨混合洪水发生频次明显增加，但总的干旱背景不会改变。  相似文献   

A DIAGNOSTIC ANALYSIS OF 1997/1998 ENSO EPISODE AND ROLE OF INTRA-SEASONAL OSCILLATION IN TROPICAL ATMOSPHERE     

翟盘茂  郭艳君  李晓燕 《热带气象学报(英文版)》2001,7(2):113-121

On the basis of comparison of 1982/1983 strong ENSO processes, key characteristics such as rapid development, immense intensity and abrupt retreat are revealed with regard to the warm episode in 1997/1998, features governing the intraseasonal oscillation for the tropical Indian Ocean and the western Pacific during its onset and evolution of the ocean and atmosphere for the process are diagnostically studied in detail.  相似文献   

浙江省近百年气温变化研究   总被引：3，自引：0，他引：3  

雷媛  孙彭龄 《气象》2001,27(10):17-19

利用浙江省近百年气温等级资料，分析全省冬季、夏季和全年气温变化，发现浙江省年气温变化总趋势与北半球、全国比较一致，但年气温上升、下降的时间比北半球、全国年气温变化有滞后现象。冬季最低气温升高，是暖冬的主要特征，夏季极端最高气温天数明显减少，是凉夏的主要特征。  相似文献   

A review of storm-surge research in China     

Liu Fengshu  Wang Xinian 《Natural Hazards》1989,2(1):17-29

In this paper are briefly introduced: (1) the general situations of storm hazards caused by different weather types; (2) the acquisition of data needed in storm-surge forecasting; (3) the current forecasting techniques of storm surges; (4) the calculations of storm surge with different return periods for coastal engineering and the exploitation of the ocean; and (5) the basic theoretical study of storm surges.  相似文献