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題名 | 寒潮之數值模擬及其能量分析 |
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作者 | 蔡清彥; 陳建河; | 書刊名 | 大氣科學 |
卷期 | 17:1 1989.03[民78.03] |
頁次 | 頁77-100 |
分類號 | 328.884 |
關鍵詞 | 能量; 寒潮; 數值模擬; |
語文 | 中文(Chinese) |
中文摘要 | 本文使用NCAR(National Center for Atmospheric Research) CFM (Community Forecast Model)波譜模式預報1978-1979冬季最強寒潮的個案,並計算其500 mb的波譜動能。從有地形模式(簡稱CFM-M)的預報結果發現在寒潮爆發期間,波數3動能有明顯的增加,因此波譜動能最大值由波數2變為波數3。波數3動能的增加主要是由於非線性項所造成,但不是任一單獨三波交互作用(interaction triad)可以解釋的。從沒有地形模式(簡稱CFM-NM)的預報結果發現,500 mb低壓槽在沒有西藏高原阻擋下亦會在70°-90°E間往南移動後滯留。此低壓槽的波數為5,因此造成在寒潮爆發期間,波譜動能的最大值由波數3不合理的往波數4、5位移的現象。而地面圖上西伯利亞冷高壓在沒有西藏高原的阻隔下會往南方移動並且強度逐漸減弱,因此臺灣地區寒潮爆發的現象並不發生。 實際大氣在寒潮爆發過後,波譜動能最大值則由波數3移回波數2。CFM-M及CFM-NM對此現象之模擬結果則十分相近。我們也使用中央氣象局(CWB)四階空間差分網格點全球模式(簡稱CFS)預報相同的個案,同時也計算500 mb的動能波譜。從有地形及沒有地形的預報結果發現,雖然不如NCAR CFM的結果理想,但的確也能夠模擬出寒潮爆發的現象。 |
英文摘要 | NCAR (National center for Atmospheric Research) CFM (Community Forecast Model) has been utilized to predict the strongest cold surge case (January 23-February 8, 1979) in winter MONEX period--Simulated spectral ernergetics at 500 mb has bee analyzed. In the cold surge period, CFM with topography (CFM-M) is able to simulate the shift of kinetic energy peak from wavenumber 2 to wavenumber 3. The main reason for the energy shift is nonlinear interaction, but not from a single interaction triad. However, simulated results by CFM without topography (CFM-NM) showed that 500 mb trough would move unrealistically southward between 70°E and 90°E and then remain stationary. The WAVENUMBER FOR THE TROUGH WOULD BE 5. Therefore, the kinetic energy in this period would shift unrealistically from wavenumber 3 to 4 and 5. In the corresponding surface maps, Siberian high pressure system would move unrealistically southward between 70°E and 90°E as well. Terefore, there would be no cold surge in the Southeast China and Taiwan area. After the cold sure, the kinetic energy peak was shifted back from wavenumber 3 to wavenumber 2. Both CFM-M and CFM-NM were able to simulate this phenomenon very well. Global Forecast system of the Central Weather Bureau (CWB GFS) was ultized to simulate the same cold surge case. The FGS with ropography (GRS-M) was able to simulate the major features of the cold surge case, even though not as good as those by NCAR CFM-M. |
本系統之摘要資訊系依該期刊論文摘要之資訊為主。