天气尺度瞬变扰动的物理分解原理  

Physical decomposition principle of regional-scale atmospheric transient anomaly

作　　者：钱维宏[1] 

机构地区：[1]北京大学大气海洋科学系,北京100871

出　　处：《地球物理学报》2012年第5期1439-1448,共10页Chinese Journal of Geophysics

基　　金：中国科学院战略先导专项(XDA05090400);国家自然科学基金项目(40975039)联合资助

摘　　要：大气变量可以在时空域内物理分解成四个部分.前两个是纬圈-时间平均的对称部分和时间平均的非对称部分,分别由太阳辐射和海陆分布热力调节的季节变化引起,并形成规则的逐日气候.第三部分是由年际和季节内的热带海洋或极地热力强迫引起的纬圈平均瞬变对称扰动,可形成大气变量的行星尺度指数循环.第四部分是一些复杂的天气尺度瞬变非对称扰动.大气变量中的逐日天气尺度瞬变扰动,可以用于指示区域持续性的干旱、暴雨、低温和热浪等极端天气事件.天气尺度瞬变扰动天气图能在极端天气事件的预报中发挥应有的作用.In a mixed space-time domain, atmospheric variables can be decomposed into the zonal time-average climate symmetric part, the time-average climate asymmetric part, the zonal-average transient symmetric anomaly, and the transient asymmetric anomaly. The first two parts are forced by the seasonal solar radiation and land-sea distribution and linked to regular daily climate. The third part is caused from intra-seasonal to inter-annual tropical or polar heating variations and shows like the planetary-scale index cycle. The last part is complex as some atmospheric transient waves or regional-scale anomalies. The daily transient anomalies of atmospheric variables can be used to indicate some extreme weather events such as the regional persistent drought, heavy rainfall, lower temperature and hot days. We suggest that the weather map of transient anomalies could be applied in forecasts of extreme weather events.

关 键 词：物理分解 天气尺度 瞬变扰动 天气图 极端天气事件 

分 类 号：P433[天文地球—大气科学及气象学]