两湖流域雨季降水气候特征分析  

Analysis on the climatic characteristics of precipitation in rainy season in the Two-lake Region

作　　者：吴贤云[1] 叶成志 王琪 Wu Xian yun;Ye Chengzhi;Wang Qi(Hunan Climate Center, Changsha 410118;Hunan Meteorological Observatory, Changsha 410118;Hunan Meteorological Service Offices, Changsha 410118)

机构地区：[1]湖南省气候中心,长沙410118 [2]湖南省气象台,长沙410118 [3]湖南省气象服务中心,长沙410118

出　　处：《暴雨灾害》2016年第6期497-503,共7页Torrential Rain and Disasters

基　　金：公益性行业(气象)科研专项(GYHY201306016)

摘　　要：利用全国740站日降水资料，采用多种统计学方法，对两湖流域雨季降水特征进行了分析。结果表明：(1)两湖流域年降水序列可分为5个阶段，其中主雨季从4月的第2候开始，持续到7月的第1候。两湖流域雨季较江淮梅雨来得早，持续的时间长。(2)雨季内以出现2个和3个主雨期模态的可能性较大。其中2个主雨期一般出现在5月上、中旬及6月中、下旬，这种模态在上世纪60年代、90年代表现明显；3个主雨期一般出现在4月中旬、5月中下旬到6月初与6月下旬至7月初，该模态在20世纪60年代后期至70年初、80年代中后期表现明显。(3)两湖流域雨季内降水的准双周(10~20d)、30~60d低频振荡现象明显。准双周振动在雨季中表现为5个波动，30~60d振荡表现为3个完整的波动，波峰分别出现4月上旬、5月上旬及6月中旬，与其降水主模态有较好的对应关系。Based on China’s 740 daily meteorological precipitation records, precipitation characteristics in rainy season in the Two-lake region have been analyzed by using several statistical methods. Results are as follows. (1) The yearly rain time series may be technically splitted into 5 stages, among which, the prime stage (called it Two-lake rainy season) starts at the second Hou (a 5-day period) of April and ends at the first Hou of July. The Two-lake rainy season, which comes earlier and stays longer, when compared to China’s Meiyu rainy season. (2) The first two modes of EOF, one with two intensive rainy periods (IRP2) and another with three (IRP3), are the most important modes and frequently appear in rainy season. The IRP2 mode, one intensive rainy period being in early to mid May and the other in mid to late June, had been significant during 1960s and 1990s, while the IRP3 mode, the intensive periods being in mid April, mid to late May to early June, and late June to early July, respectively, had been significant during the late 1960s to early 1970s, as well as the mid to late 1980s. (3) The quasi two-week (10-20 days) and 30-60-day oscillations are remarkable in the Two-lake rainy season. The former includes 5 complete waves and the latter includes 3 with peaks at early April, early May and mid June, being well corresponded to its first EOF’s mode.

关 键 词：两湖流域 雨季 EOF 分解 EEMD 低频振荡 

分 类 号：P468.024[天文地球—大气科学及气象学]