摘要
利用197l-2007年云南124站逐日降水资料计算雨季开始期,采用EOF(经验正交函数)分解和最大熵谱分析方法,研究云南雨季开始期的空间分布、时间演变及周期变化特征,并初步分析云南雨季开始期不同分布型与季风的关系,以期为指导春季农业生产提供依据。结果表明,全省雨季开始期一致偏早或偏晚为云南雨季开始期的最主要空间分布特征,其次为滇中及以东地区与滇西北及滇西南地区雨季开始期反向变化的空间分布型;雨季开始期全省一致分布型存在3～5a的显著周期变化,滇中及以东地区与滇西北及滇西南地区雨季开始期反向变化的空间分布型存在3～4a的显著周期变化;云南雨季开始期与同年5月孟加拉湾地区和南海地区OLR有显著的相关关系(P<0.05);南亚季风与南海季风强度指数对云南雨季开始期有重要的指示性意义。
The spatial distribution, temporal evolution and periodic variation character of the beginning date of rainy season in Yunnan were studied by using of EOF （ Empirical orthogonal function ） and maximum entropy spectral analysis method based on daily precipitation data at 124 rainfall stations from 1971 to 2007. The relationship between different distribution patterns of the beginning date of rainy season and monsoon was also analyzed. The results showed that the first main spatial distribution feature was that the whole province＇s beginning date of rainy season was unanimously earlier （or later） than normal time, the second feature was reverse spatial distribution between the middle, namely the eastern and the southern and western of Yunnan. The obviously 3 - 5 years oscillation period existed in the first main spatial distribution. The obviously 3 -4 years oscillation period existed in the second main spatial distribution feature. There was obviously correlation between the beginning date of rainy season and the OLR over the Bay of Bengal region and the South China Sea region in May in the same year. The intensity indexes of South Asia monsoon and the South Sea monsoon were of great indicative significance in the the beginning date of rainy season in Yunnan province.
出处
《中国农业气象》
CSCD
北大核心
2012年第3期348-354,共7页
Chinese Journal of Agrometeorology
基金
国家自然科学基金项目(41065008)
云南省社会发展科技计划(2009CA023)
国家自然科学联合基金重点项目(V1133603)
关键词
雨季开始期
EOF
南亚季风
南海季风
The beginning date of rainy season
EOF
South Asia Monsoon
South China Sea Monsoon
