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題 名 | 普渡區域模式模擬東亞夏季季風之評估=An Evaluation of the East Asian Summer Monsoon Simulation by the Purdue Regional Model |
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作 者 | 于宜強; 許晃雄; 柯文雄; 鄒治華; 許武榮; 商文義; | 書刊名 | 環境保護 |
卷 期 | 27:1 2004.06[民93.06] |
頁 次 | 頁40-56 |
分類號 | 328.5 |
關鍵詞 | 區域氣候模式; 年際變化; 季內震盪; Regional climate model; Interannual variation; Intraseasonal oscillation; |
語 文 | 中文(Chinese) |
中文摘要 | 本研究利用普渡區域模式(Purdue Regional Model, PRM)進行五年5至8月模擬,針對模式結果進行大氣環流及地表變數的驗證,同時為求客觀及數量化,亦利用氣候統計方法評估模擬結果,以便了解PRM 模擬東亞夏季季風的能力。除了降雨外,其他模擬變數的誤差均很小,型態相關(pattern correlation)也相當高(大於0.9)。降雨誤差的進一步分析,發現PRM 5至8月的模擬,存在一個明顯的系統性誤差結構。若將此系統性誤差扣除,降雨的模擬誤差值與型態相關均大幅提升。在年際變化模擬方面,PRM模擬的各年夏季雨量距平值均與觀測值同相(即正負號相同)。比如,1996年與1998年期間,東亞與台灣地區平均降雨偏少,1997、1999及2000年平均降雨則為偏多。資料顯示,東亞與台灣地區降雨與氣壓的年際變化呈現明顯負相關,亦即850hPa高度場距平值與降雨距平值反號。PRM成功的模擬此一現象。在季內振盪方面,模式模擬的30~60天低頻訊號,在南海地區的強度與相位均與觀測資料相似。綜觀以上結果,PRM在東亞夏季季風的模擬,不論是氣候平均、年際變化或季內振盪,都有相當令人滿意的表現。 |
英文摘要 | This study used the Purdue Regional Model (PRM) to simulate the East Asian summer monsoon for the 5 summers from 1996-2000. Objective statistical methods and comparisons between the simulated and observed circulation and surf ace variables were performed to evaluate the performance of the PRM. All simulated variables except precipitation exhibit small errors and high pattern correlations with the observed. An analysis of the precipitation errors reveals the existence of a spatially-coherent systematic error pattern. After removing this pattern, the precipitation errors reduce significantly and the pattern correlations rise from 0.3-0.4 to 0.6-0.8. The signs of the simulated regional-averaged precipitation anomalies are the same as the observed (e.g., negative anomalies in 1996 and 1998 and positive anomalies in 1997, 1999 and 2000). This result indicates the well-simulated interannual variability by the PRM. The PRM also simulated the observed negative correlation between the 850hPa geopotential high and the precipitation in East Asia and Taiwan. In the intraseasonal time scale, the PRM well simulated the fluctuations of the 850hPa vorticity in both amplitude and phase in the South China Sea. Overall speaking, the PRM is able to simulate the East Asian summer monsoon variability from sub-seasonal to interannual time scale. |
本系統中英文摘要資訊取自各篇刊載內容。