| 摘要: |
| 利用我国西南地区97个国家地面基准观测站的逐日观测资料、全球降水气候中心（GPCC）月平均降水资料以及NCEP/NCAR逐月再分析资料，分析了由青藏高原地面加热场强度距平指数（Tibetan Plateau surface heating anomaly index，简称TPSHAI）与当年西南地区春季降水之间存在的可能联系。结果表明，1月份的TPSHAI在2001年以前呈逐年减弱的趋势，近几年又开始出现显著增强。当1月的青藏高原地面加热场强度距平指数异常偏高（低），即青藏高原热力作用异常偏强（弱）时，在后期春季的青藏高原上空激发异常的纬向环流圈，而在高原南侧副热带低层大气和西北太平洋上分别存在一个异常反气旋和异常气旋式环流，使得西南地区的南部与北部处在不同垂直运动及水汽输送的环流背景之下，加上对流层高层西风带中欧亚地区的Rossby波列传播引起的东亚大槽异常偏东、南支槽活动异常偏北的影响，西南地区的春季降水容易出现东北部异常偏多（少），而在广大的中部以西以南地区异常偏少（多）的分布特征。反之亦然。 |
| 关键词: 西南地区；春季降水；青藏高原；环流异常 |
| DOI： |
| 投稿时间：2018-10-21修订日期：2019-01-29 |
| 基金项目: |
|
| The Response of Spring Precipitation over Southwest China to Surface Heating Effect of Qinghai-Tibet Plateau |
| Long yuan |
| (Meteorological Bureau of Liupanshui) |
| Abstract: |
| Based on the station precipitation data from NMC and GPCC as well as reanalysis data from NCEP/NCAR, the possible relationships between spring precipitation over Southwest China with the heating effect of Qinghai-Tibet Plateau during 1951-2013 have been investigated. The results show that the spring rainfall over Southwest China gradually increased from northwest to southeast. The T-P surface heating anomaly index of Jan have a tendency to decrease before 2001, but significantly enhance in recent years. There is a close relationship between the T-P surface heating in the early winter and the spring precipitation over Southwest China. When the T-P surface heating in January is strong (weak), it will motivate a anomaly zonal circulation loop on the Qinghai-Tibet Plateau and the anomaly anticyclone on subtropical lower atmosphere of south plateau, as well as anomaly cyclone on northwest Pacific Ocean. Its combined action make the south and north of Southwest China under the separate circulation background of vertical motion and vapor transport, caused the spring precipitation over Southwest China is abnormal less (more)in the southern and more(less) in the central and northeast. |
| Key words: Southwest China; Spring Precipitation; Qinghai-Tibet Plateau; Circulation Anomaly |
