STUDY ON THE MULTIVARIATE STATISTICAL ESTIMATION OF TROPICAL CYCLONE INTENSITY USING FY-3 MWRI BRIGHTNESS TEMPERATURE DATA  

作　　者：张淼 邱红 方翔 卢乃锰 

机构地区：[1]Key Lab of Radiometric Calibration and Validation for Environmental Satellites, China Meteorological Administration (LRCVES/CMA) and National Satellite Meteorological Center, Beijing 100081 China

出　　处：《Journal of Tropical Meteorology》2017年第2期146-154,共9页热带气象学报（英文版）

基　　金：National Key Research and Development Program of China(2016YFA0600101);National Basic Research Program of China(973 Program,2010CB950802);National Natural Science Fund(41605028)

摘　　要：A technique for estimating tropical cyclone(TC) intensity over the Western North Pacific utilizing FY-3Microwave Imager(MWRI) data is developed. As a first step, we investigated the relationship between the FY-3 MWRI brightness temperature(TB) parameters, which are computed in concentric circles or annuli of different radius in different MWRI frequencies, and the TC maximum wind speed(Vmax) from the TC best track data. We found that the parameters of lower frequency channels' minimum TB, mean TB and ratio of pixels over the threshold TB with a radius of 1.0 or 1.5 degrees from the center give higher correlation. Then by applying principal components analysis(PCA)and multiple regression method, we established an estimation model and evaluated it using independent verification data, with the RMSE being 13 kt. The estimated Vmax is always stronger in the early stages of development, but slightly weaker toward the mature stage, and a reversal of positive and negative bias takes place with a boundary of around 70 kt. For the TC that has a larger error, we found that they are often with less organized and asymmetric cloud pattern, so the classification of TC cloud pattern will help improve the acuracy of the estimated TC intensity, and with the increase of statistical samples the accuracy of the estimated TC intensity will also be improved.A technique for estimating tropical cyclone（TC） intensity over the Western North Pacific utilizing FY-3Microwave Imager（MWRI） data is developed. As a first step, we investigated the relationship between the FY-3 MWRI brightness temperature（TB） parameters, which are computed in concentric circles or annuli of different radius in different MWRI frequencies, and the TC maximum wind speed（Vmax） from the TC best track data. We found that the parameters of lower frequency channels＇ minimum TB, mean TB and ratio of pixels over the threshold TB with a radius of 1.0 or 1.5 degrees from the center give higher correlation. Then by applying principal components analysis（PCA）and multiple regression method, we established an estimation model and evaluated it using independent verification data, with the RMSE being 13 kt. The estimated Vmax is always stronger in the early stages of development, but slightly weaker toward the mature stage, and a reversal of positive and negative bias takes place with a boundary of around 70 kt. For the TC that has a larger error, we found that they are often with less organized and asymmetric cloud pattern, so the classification of TC cloud pattern will help improve the acuracy of the estimated TC intensity, and with the increase of statistical samples the accuracy of the estimated TC intensity will also be improved.

关 键 词：tropical cyclone intensity multivariate statistical estimate FY-3 microwave imager 

分 类 号：P444[天文地球—大气科学及气象学]