應用衛星資料在梅雨季海上中尺度對流系統生成前兆之初步探討

A Preliminary Study on the Genesis of Mesoscale Convection System during Mei-Yu Period Using Satellite Data

劉崇治(Chung-Chih Liu) ； 劉振榮(Gin-Rong Liu)

《大氣科學》 28卷4期 (2000/12) Pp. 317-341

摘要

本研究利用日本GMS-5(Geostationary Meteorological Satellite)地球同步衛星的紅外分裂窗區頻道與美國國防氣象衛星計畫(Defense Meteorological Satellite Program; DMSP)所發射衛星上的SSM/I(Special Sensor Microwave/Imager)微波輻射計各頻道亮度溫度資料，建立了適合台灣及南海附近海域使用的海面溫度、近海面空氣濕度及近海面風速的反演方程式。另外使用劉和劉(1999)所提出的近海面空氣溫度估算的改進方法，透過總體參數公式，針對1997及1998兩年梅雨季海氣間各種參數的估算進行測試。結果顯示，利用SSM/I資料反演海面溫度、近海面空氣溫度及濕度的均方根誤差與相關係數分別為1.2K、1.6K、1.43g/kg與0.96、0.96、0.95；利用GMS-5資料的反演結果，則分別為1.7K、1.7K、1.71g/kg與0.79、0.74、0.72，並且兩種衛星的估算結果也有很好的一致性。
此外本研究也利用EC/TOGA的分析資料搭配SSM/I所反演的各種海氣參數進行大尺度綜觀環境條件的分析。結果顯示，在海上中尺度對流系統發展之前，無論綜觀環境是否具備有利的激發條件，由海面向空氣中傳遞的能量通量都有增加的趨勢，這意味著海氣交互作用和海上中尺度對流系統的生成與發展，應該有相當的關係存在。本文只是利用衛星資料，就梅雨期海上中尺度對流系統生成前兆的研究方面，初步地建立一套輔助的分析方法與技術，後續仍然値得深入的研究與探討。

關鍵字

海氣參數 ； 中尺度對流系統 ； 海氣交互作用

並列摘要

With data sets gained from DMSP (Defense Meteorological Satellite Program) SSM/I (Special Sensor Microwave/Imager) microwave channels,GMS-5 (Geostationary Meteorological Satellite) infrared channels, ship-measured and buoys data, the statistical algorithms to estimate sea surface temperature, near-sea surface air humidity and wind speed are established. Near-sea surface air temperature is estimated by the improved algorithm proposed by Liu and Liu(1999). Sensible and latent heat flux between atmosphere and ocean are estimated by using bulk formula. The results show that good accuracy and consistency between SSM/I and GMS-5 data. The accuracy of this result implies strong potential for application of satellite data gained through remote sensing to relative studies and operational work in the ocean-atmosphere interaction. Two cases of mesoscale convection systems (MCS) over oceans were selected in this study, Investigations were carried by using the data of EC/TOGA and air-sea parameters from SSM/I. The results show that regardless of whether the environmental conditions were beneficial to the genesis and development of convective cloud clusters over the ocean or not, the interactions between the atmosphere and the ocean seem to be related to the genesis and development of such MCSs. More cases will be studied and a quantitative, objective warning index could be addressed in the future.

並列關鍵字

Air-Sea parameters ； MCS ； Interaction between atmosphere and ocean