摘要
本文用地气耦合非定常距平模式对1980~1982年及1986~1988年共6年的个例进行了距平场的季(3~6月)预报试验。通过两种方法,一是在时间积分过程中改变时间过滤公式中的过滤系数β(分别取为0.05和0.1);二是对初始场进行滤波和不滤波的比较试验来考察高频扰动及非行星波对距平场月、季预报的影响。试验表明,行星波和大气长波对距平场的月和季演变有不同的作用。长波对月以内的过程作用较大,滤掉长波使预报效果变差。而长波对季以上过程的作用较小,甚至有某种干扰性的“噪声”作用,滤掉长波使季预报的效果得到改进。
In order to examine the effects of high frequency disturbances and non-planetary waves on monthly and seasonal forecast, a nonsteady atmosphere-earth surface coupled anomaly model is applied to a series of seasonal (from March to June) forecast experiments for the anomaly fields from 1980 to 1982 and from 1986 to 1988. Two methods are used in the experiments: (l) to change the filter coefficient in time filter formula during the time integration, (2) to change the components of the waves involved in initial fields, i.e. to remain or to remove the non-planetary waves. It is found that planetary waves and long waves have different effects on the monthly and seasonal evolution of anomaly field. The long waves is more important to intra-month processes. Filtering long waves will make the results of monthly forecast poor. But, long waves is less important and even is certain interfering 'noise,, for.over-seasonal processes. Filtering out long waves will improve the results of seasonal forecasts.
出处
《大气科学》
CSCD
北大核心
1996年第5期556-564,共9页
Chinese Journal of Atmospheric Sciences
基金
中国科学院"KY85-10"项目
关键词
距平模式
季预报
初始场滤波
时间过滤
anomaly model seasonal forecasts initial field filter time filter