气象科学2017，Vol.37Issue(6)：718-726,9.DOI:10.3969/2016jms.0072
北半球平流层极涡崩溃早晚的环流特征及其对5月南亚降水的影响
Inter-annual variation of the Northern Hemisphere stratospheric polar vortex breakdown and its impact on the precipitation over the South Asia in May
摘要
Abstract
Based on NCEP/NCAR monthly mean reanalysis,CMAP and GPCP monthly mean precipitation datasets over the period of 1979-2014,the inter-annual characteristics of the stratospheric polar vortex breakdown and its relationship with the precipitation over the South Asia in May were studied.Results show that the Northern Hemisphere stratospheric polar vortex breakdown is characterized by interannual variations.In addition,as the stratospheric polar vortex breaks down early (late),abnormal signals propagate downward from the stratosphere in March and reaches upper troposphere in April,with high (low) temperature,weak(strong) polar vortex,weak(strong) polar jet above the upper troposphere.It is also found that inter-annual variations of the stratospheric polar vortex breakdown are closely related to the precipitation anomalies over the South Asia in May.As the stratospheric polar vortex breaks down late,in the stratosphere,the negative geopotential height anomalies dominate over the Arctic region while the positive geopotential height anomalies over the middle latitudes in April.These positive geopotential height anomalies over the middle latitudes propagate downward and even reach the upper troposphere above the North Arabian Sea in May,which act to form a favorable condition for precipitation over the South Asia,and vice versa.关键词
北半球平流层极涡崩溃/南亚降水/年际变化Key words
Northern Hemisphere stratospheric polar vortex breakdown/Precipitation over the South Asia/Inter-annual variation分类
天文与地球科学引用本文复制引用
沈熙,徐海明,胡景高..北半球平流层极涡崩溃早晚的环流特征及其对5月南亚降水的影响[J].气象科学,2017,37(6):718-726,9.基金项目
国家自然科学基金资助项目(41490643 （）
41575077 （）
41275094 （）
41505034) （）
江苏省333工程(BRA2015290) （BRA2015290）
江苏高校优势学科建设工程项目(PAPD) （PAPD）
南京信息工程大学人才启动经费(2014R010) （2014R010）
