青藏高原夏季风和南海夏季风低频振荡的关系

Study on Relationship of Low Frequency Oscillation between Summer Monsoon in Qinghai-Xizang Plateau and Summer Monsoon in South China Sea

利用1948-2010年NCEP/NCAR全球大气逐日平均的再分析资料分析了青藏高原夏季风和南海夏季风大气低频振荡的可能关系。结果表明,夏半年高原地区和南海地区季风均存在明显的30~50天的振荡周期,并且两者在这个振荡周期上存在明显的位相关系,即南海夏季风的低频振荡比青藏高原夏季风提前约3/4个位相,对500 h Pa和850 h Pa低频风场的研究也得出同样的结果。两者存在明显位相关系的原因之一可能是3月下旬开始南海向青藏高原地区的低频输送。

The possible relationship of the low frequency oscillation betw een summer monsoon in the Qinghai-Xizang Plateau and summer monsoon in the South China Sea are studied by using the daily average NCEP / NCAR reanalysis data for the time period of 1948-2010. The results show that the areas of the Qinghai-Xizang Plateau monsoon and the South China Sea monsoon were obvious periodic oscillation of 30 ~ 50 days in the summer half year,and both exist obvious phase relationship in this apparent oscillation,namely low frequency oscillation of the South China Sea monsoon are in advance than summer monsoon in the Qinghai-Xizang Plateau about 3 /4phase,and the 500 h Pa and 850 h Pa wind field studies have reached the same conclusion. Moreover,one of the possible reasons of the phase relationship betw een the two kinds of monsoon is the low frequency transmission from the South China Sea to the Qinghai-Xizang Plateau starting from late March.