應用氣象衛星資料估算地球出長波輻射之研究

Derivation of Outgoing Longwave Radiation from Meteorological Satellite Data

劉振榮(G. R. Liu) ； 林祐仲(Y. J. Lin) ； 郭宗華(T. H. Kuo)

《大氣科學》 26卷1期 (1998/03) Pp. 77-93

摘要

本研究利用NOAA-12繞極衛星的極精密高解析輻射計AVHRR和高分辨率紅外線探測器HIRS的資料組合來估算0.5°×0.5°經緯度網格的OLR，並進一步利用日本GMS-5地球同步衛星資料來計算全天候OLR，以做為出長波輻射的監測與應用。比較本研究利用HIRS資料所估算的OLR值和ERBS衛星所實測到的OLR值，結果發現其均方根誤差為19.669W/m^2，平均偏差為1.813W/m^2。而利用AVHRR資料所估算的OLR值均方根誤差為22.694W/m^2，平均偏差為1.687W/m^2。另外，利用GMS-5觀測資料所估算的OLR值均方根誤差為21.19W/m^2，平均偏差為-0.24W/m^2。整體而言，本研究利用三種不同的衛星資料所估算的OLR值與ERBS衛星觀測值比較結果顯示：本研究的估算方法與程序具相當的實用性與精確性，就其OLR分布圖來看，兩者非常近似，同時本研究所估算的OLR和雲圖、降雨資料的比較亦十分吻合。本研究另試圖利用估算得到的OLR來判斷南海夏季季風肇始的日期，分析結果顯示1995年南海夏季季風肇始的日期約為5月10日，這結果和其他學者的研究結果相符。

關鍵字

出長波輻射 ； 氣象衛星 ； 東亞季風

並列摘要

This Study uses three meteorological satellite data, NOAA HIRS, NOAA AVHRR and GMS-5 data, to derive 0.5°×0.5° latitude-longitude outgoing longwave radiation (OLR). In this study, HIRS and AVGRR data are combined to compute daily OLR and GMS-5 data are used to compute hourly OLR. The application of derived OLR is also investigated to evaluate the application potential of these derived OLR.Comparisons between the derived OLR and the observed OLR by ERBS (Earth Radiation Budget Satellite) show that the RMSE for three different satellite data is 19.67, 22.69 and 21.19 W/m^2, respectively; and the bias 1.81, 1.69 and -0/24 W/m^2, respectively. This study also compare the derived OLR to other data, such as cloud cover and rainfall data. The comparisons show that there are good physical relationships between these data. Overall, the results reveal the OLR derivation procedures established by this research are practical and accurate. Besides, the application of derived OLR in the determination of the onset day of 1995 summer monsoon over the South China Sea area is executed. The analysis by this study points out the onset day is about May 10. This conclusion is similar to other research terms' results.

並列關鍵字

Outgoing longwave radiation(OLR) ； Meteorological satellite ； Asian monsoon