中央氣象局全球模式之氣候特徵：東亞夏季季風

Climate Characteristics of the CWB Global Model: East Asian Summer Monsoon

胡志文(Jyh-Wen Hwu) ； 馮欽賜(Chin-Tzu Fong) ； 汪鳳如(Feng-Ju Wang) ； 陳建河(Jen-Her Chen) ； 鄭明典(Ming-Deng Cheng)

《大氣科學》 30卷2期 (2002/06) Pp. 99-116

摘要

本文以中央氣象局全球模式10年的積分結果，探討模式對東亞夏季季風的模擬能力。此結果將作為未來發展中央氣象局氣候模式及模式改進的重要依據。
經由模式結果的分析，吾人可得到下列的結論。模式有能力模擬出夏季期間的大尺度環流場，如北半球陸地的低壓及洋面上的高壓、緯向平均溫度場、風場及溼度場等。在東亞夏季季風的演化上，模式能合理掌握東亞夏季季風肇始期間大尺度系統的演變，如上對流層南北溫度梯度逆轉、高層東風的出現、低層較大西南風場及較大降水等現象，季風肇始後模式也有能力模擬出太平洋副高及降水的北移現象。由於模式並非完美，因此模擬結果有某些系統性誤差存在。文中對改進模式系統性誤差的方法有初步的探討。

關鍵字

大氣環流模式 ； 氣候模擬 ； 東亞夏季季風

並列摘要

This study is focused on the analysis of a 10 years integration of general circulation model (Global Forecast System) in Central Weather Bureau. The primary target of the analysis is East Asian summer monsoon. The result of this study will be served as a guideline for the further development and improvement of the model.
From the analyzed of model result, it is shown that model is capable to simulate the large scale circulation patterns in summer, such as the low pressure in land surface and high pressure over ocean in Northern Hemisphere, zonally averaged temperature, wind and moisture field. On the evolution of East Asian summer monsoon, model can capture the onset signals in East Asia such as the reverse of north-south temperature gradient, the appearance of upper level easterly, the commencement of stronger southwesterly in low level, organized precipitation. After the onset of East Asian summer monsoon, model also has the ability to simulation the northward migrations of subtropical tropical high in Pacific Ocean and East Asian rain belt. Due to the fact that model is not perfect, there are some systematic biases exist in model simulation. Some preliminary discussions on how to alleviate model's systematic biases are included.

並列關鍵字

General circulation model ； Climate simulation ； East Asian summer monsoon