摘要
利用1948-1999年的NCEP/NCAR再分析月平均高度场和风场资料,根据气候平均850hPa高度场和流场的季节演变特征,客观地定义了描述马克斯林高压活动的特征参数,对马斯克林高压的变化特征进行了系统的诊断分析。结果表明,马斯克林高压季节变化明显,南半球冬季最强,位置偏西、偏北,夏季反之。对马斯克林高压异常变率的分析表明,马斯克林高压具有明显的年际变化,ENSO对马斯克林高压面积有一定影响,但对马斯克林高压中心位置和强度影响不大。同时马斯克林高压的强度和位置还存在显著的年代际变化,在研究的52年时间内,马斯克林高压面积和中心强度是逐渐增大、增强的,而中心位置是缓慢东移、南移的。
By using the NCEP/NCAR monthly mean reanalysis data from 1948 to 1999,the characteristic indexes are defined to describe the Mascarene High （MH）, based on the evolution characteristics of the climatological geopotential height and streamline fields at 850 hPa. By calculating the indexes, the features of the MH variations on different time scales are examined. The results show that the seasonal variations of MH were remarkable： it was the strongest and the location is more westward and northward in southern winter, and vice versa in southern summer. The anomaly variations of MH are also studied. It is shown that MH had the obvious interannual and interdecadal variations. On the interdecadal time scale, the area and center intensity of MH increased gradually, and the center location moved eastward and southward slowly in 52 years.
出处
《气象科技》
2008年第1期35-42,共8页
Meteorological Science and Technology
关键词
马斯克林高压
季节变化
年际变化
年代际变化
Mascarene high, seasonal variation, interannual/interdecadal variation
