江南地区近31a的大气环流分型及与温度场演变的关系

Classification Characteristics and Application Analysis of Synoptic Flow Patterns during 1987-2017 over the Jiangnan Region

摘要: 本文应用Lamb-Jenkinson大气环流分型方法，利用1987~2017年的逐日平均海平面气压资料，计算了江南地区逐日的6个环流指数及相应的环流分类，分析了江南地区不同季节各种环流类型出现的频率及其变化特征。通过对27类逐日环流分型结果的统计分析得出：江南地区主导环流类型依次为E型、N型和AE型，其频率分别为33.15%、22.62%和13.61%，划分的环流型符合实际情况。春季江南地区主导环流为N、AN型；夏季主导环流类型较复杂，主导环流为N、CN、SE及C型；秋季和冬季主导环流均有E型与N型，但冬季AN型环流出现频率比E、N型高。通过主导环流型和江南地区气温之间变化规律的分析可知：冬季在AN型控制下，江南地区多为低温天气，夏季在CN型环流控制下，江南地区气温较高。

Abstract: In this thesis, by using the Lamb-Jenkinson atmospheric circulation classification method, the daily average sea level pressure data of 1987-2017 years are used to calculate the 6 circulation indices and analyzed the frequency and variation characteristics of different circulation types in different seasons in Jiangnan region. According to the statistical analysis of the 27 types of daily circulation, the major circulation types in the south of the Jiangnan region are E, N and AE, with the frequency of 33.15%, 22.62% and 13.61% respectively. The dominant circulations of the Jiangnan region in spring are N and AN types; the types of dominant circulation in summer are more complex, and the dominant circulation is N, CN, SE, and C types; the dominant circulations in autumn and winter are E-type and N-type, but the frequency of AN-type circulation in winter is higher than E and N types. According to the analysis of the changing rule between the dominant circulation type and the temperature in the south of the Yangtze River, under the control of the AN type, the Jiangnan region is mostly cold weather, and under the control of the CN type circulation in the summer, the temperature in the Jiangnan region is higher.