动力延伸(月)数值天气预报中的信息提取和减小误差试验

用一个全球谱模式通过较多个例的月数值天气预报试验,研究了预报结果的有用信息提取问题.模式预报误差的谱分析表明,纬向平均(零波)场误差占很大比例,试验了两种用气候倾向改善纬向平均(零波)场误差的方案,一是对逐日预报结果进行订正,二是在积分过程中进行订正,两种方案都取得了一定成效.

A Study of Information on the Extraction to Reduce Errors in Dynamic Extended (Monthly) Numerical Weather Prediction

A number of monthly numerical weather prediction cases based on a global spectral model have been used to study the extraction of useful information in the predicted results. Spectral analysis of model prediction errors shows that the zonal symmetric part (" wave-number zero" ) accounts for a large portion of the total error. Using climatic tendency, two approaches have been tested to reduce this part of error. The first is to correct the final forecast result by replacing the zonal symmetric component by its climatic counterpart. The second is to proceed the correction of this part during the integration pro- cess. Both approaches prove effective.