梅州市冬季降水异常的环流对比分析

利用1960—2016年逐年冬季的NCEP再分析资料资料,以及国家气候中心公布的气候指数资料对梅州冬季降水异常事件进行分析。结果表明:梅州冬季降水与同期500 hPa高度场、850 hPa风场及海温场的特征存在显著的相关。冬季降水异常偏多年,500 hPa位势高度上,乌拉尔山高压脊偏强,北亚高纬度地区纬向环流显著,副高强度偏强,高原槽活跃,低纬度存在较大的位势高度正距平,中低纬的南支西风气流风速较大,南支西风带低槽活跃,锋区降水偏多。850 hPa风场上,菲律宾上空为距平反气旋环流,有利于低纬的暖湿气流从南海北部输送至华南上空。海温场上,赤道中东太平洋海域为大范围的正值区,是典型的El Nino型。冬季降水异常偏少年则反之。

Circulation Contrast Analysis of Winter Precipitation Anomalies in Meizhou

Using NCEP reanalysis data from 1960 to 2016, and the climate index data released by the National Climate Center, this paper analyzes the winter precipitation anomalies in Meizhou. The results show that there is a significant correlation between the winter precipitation in Meizhou and the characteristics of the 500hPa height field, 850hPa wind field and SST field. The winter precipitation years, 500hPa geopotential height, Ural ridge is strong, the northern high latitude zonal circulation significantly, the strength of the subtropical high is strong, active plateau trough, low latitude has large potential highly positive anomaly, the South Branch of the westerly airflow velocity low latitude is larger, the cyclonic vorticity increase, the South branch westerly trough is more active, more precipitation in the frontal zone. On the 850hPa wind field, the cyclone over the Philippines is a cyclonic cyclone, which is favorable for the transport of warm and humid air from the lower part of the northern South China Sea to Southern China. In the SST field, the equatorial mid eastern Pacific Ocean is a large positive region, and is a typical El Nino type.