The Response of Anomalous Vertically Integrated Moisture Flux Patterns Related to Drought and Flood in Southern China to Sea Surface Temperature Anomaly          下载免费PDF全文

董娜  徐祥德  蔡雯悦  王春竹  赵润泽  魏凤英  孙婵 《热带气象学报(英文版)》2023,29(2):179-190

With the extreme drought (flood) event in southern China from July to August in 2022 (1999) as the research object, based on the comprehensive diagnosis and composite analysis on the anomalous drought and flood years from July to August in 1961-2022, it is found that there are significant differences in the characteristics of the vertically integrated moisture flux (VIMF) anomaly circulation pattern and the VIMF convergence (VIMFC) anomaly in southern China in drought and flood years, and the VIMFC, a physical quantity, can be regarded as an indicative physical factor for the "strong signal" of drought and flood in southern China. Specifically, in drought years, the VIMF anomaly in southern China is an anticyclonic circulation pattern and the divergence characteristics of the VIMFC are prominent, while those are opposite in flood years. Based on the SST anomaly in the typical draught year of 2022 in southern China and the SST deviation distribution characteristics of abnormal draught and flood years from 1961 to 2022, five SST high impact areas (i.e., the North Pacific Ocean, Northwest Pacific Ocean, Southwest Pacific Ocean, Indian Ocean, and East Pacific Ocean) are selected via the correlation analysis of VIMFC and the global SST in the preceding months (May and June) and in the study period (July and August) in 1961-2022, and their contributions to drought and flood in southern China are quantified. Our study reveals not only the persistent anomalous variation of SST in the Pacific and the Indian Ocean but also its impact on the pattern of moisture transport. Furthermore, it can be discovered from the positive and negative phase fitting of SST that the SST composite flow field in high impact areas can exhibit two types of anomalous moisture transport structures that are opposite to each other, namely an anticyclonic (cyclonic) circulation pattern anomaly in southern China and the coastal areas of east China. These two types of opposite anomalous moisture transport structures can not only drive the formation of drought (flood) in southern China but also exert its influence on the persistent development of the extreme weather.  相似文献   

一维时变冰雹云模式研究(一)——反映雨和冰雹谱的双参数演变   总被引：7，自引：4，他引：7       下载免费PDF全文

许焕斌  王思微 《气象学报》1985,43(1):13-25

在一般的冰雹云参数化模式中,水凝结物粒子分布谱的截距取为常数,这样就严重地歪曲了云水和雨水以及雨水和冰雹之间的自然演变。为了改进这个图象,我们取消了这一限制,引入了雨水、冻雨和冰雹浓度连续方程,并重新给定了冻雨,冰雹的谱形式。 根据这些假定,我们导出了每个方程中的发生项表达式,建立了一个新的一维时变参数化模式,这个模式可以较好地描述各种不同类型的水凝物粒子间的相互作用,计算结果表明,云物理图象有了明显地改善。  相似文献