摘要
利用1961～2006年NCEP/NCAR全球月平均再分析资料以及云南省124站5月降水资料,研究前期1～4月南半球大气环流对云南5月降水的影响。结果表明:前期1～2月影响的关键区主要位于南半球中纬西风带,当南半球中纬西风带位势高度偏高(低)时,5月降水易偏多(少),前期1月,南极绕极波北线与5月降水显著正相关。前期3月,南极地区影响显著,到前期4月时,南半球中高纬环流的影响减弱,热带太平洋的影响加强,当南方涛动处于正(负)位相时,5月降水易偏多(少)。前期1～4月,太平洋上空出现经向分布的波列结构,该波列结构在对流层低层到高层都存在且随时间不断变化,太平洋地区有可能是影响5月降水旱涝异常的另一个的关键区。
Based on NCEP/NCAR monthly global reanalysis data and May precipitation of 124 meteorological stations in Yunan during 1961 to 2006,this research reveals atmospheric circulation of the southern hemisphere from January to April influences on May precipitation of Yunnan.The results show there was a significantly positive correlation between the north line of Antarctic Circumpolar Wave in January and May precipitation in Yunnan,and in January and February,the influencing significant key area was located in the southern hemisphere mid-latitude westerly belt,when the southern hemisphere mid-latitude westerlies geopotential height was higher（lower）,May precipitation would be more（less）.In March,the key area was located in the Antarctic,when the Antarctic polar vortex geopotential height was higher（lower）,May precipitation would be more（less）.In April,southern hemisphere middle and high latitude circulation influence weakened,but influences of tropical Pacific enhanced,when the Southern Oscillation in the positive（negative） phase,May precipitation would be more（less）.From January to April,meridional wave structure appeared over the Pacific,the wave was basically consistent from low level to high level in troposphere and changed with the time,the Pacific region would be another influencing key area for May precipitation of Yunnan.
出处
《干旱气象》
2011年第4期407-415,共9页
Journal of Arid Meteorology
基金
国家自然科学基金项目(41075072)
云南大学研究生科研课题项目(ynuy201051)资助
关键词
南半球大气环流
云南5月降水
南方涛动(SO)
南极绕极波
显著关键区
atmospheric circulation in the southern hemisphere
May precipitation of Yunnan
Southern Oscillation（SO）
Antarctic Circumpolar Wave（ACW）
significantly key area
