利用不同再分析资料对比分析大西洋年代际变率对国内降水的影响

Comparative Analysis of the Influence of Atlantic Interdecadal Variability on Domestic Precipitation Using Different Reanalysis Data

大西洋年代际变率(AMV),是指发生在北大西洋区域的海表温度准周期性冷暖异常变化。同时使用CMAP和NCEP/NCAR、ERA-interim两套再分析资料,对比分析AMV对夏季国内降水的影响。在AMV暖位相期:夏季,中国新疆部分地区、苏南浙北一带的气温在两套再分析资料中均偏高;在中国西藏、青海、甘肃、江淮地区及华南地区,降水偏多;而在东北华北地区,降水偏少。南海区域的负相关在这两套再分析资料中是一致的,而长江中下游地区的正相关只出现在ERA-interim再分析资料上。由此可见,针对AMV对国内夏季降水的影响,ERAinterim资料比NCEP/NCAR资料的降水场更为可信,更加适合用于研究国内夏季降水。

The Atlantic interdecadal variability(AMV)refers to the quasi periodic cold warm anomaly of sea surface temperature in the North Atlantic region.In this paper,CMAP,NCEP/NCAR and era interim reanalysis data are used to analyze the impact of AMV on summer precipitation in China.In the AMV warm phase:in summer,the temperature in parts of Xinjiang,Southern Jiangsu and Northern Zhejiang is higher than that in the two sets of reanalysis data;In Tibet,Qinghai,Gansu,Jianghuai and South China,the precipitation is relatively high;In the northeast and North China,the precipitation is less.The negative correlation of the South China Sea region is consistent in the two sets of reanalysis data,while the positive correlation of the middle and lower reaches of the Yangtze River region only appears in the era interim reanalysis data.Therefore,the precipitation field of era interim data is more reliable than NCEP/NCAR data,which is more suitable for the study of summer precipitation in China.