The numerical forecast result for tropical cyclone paths from 2006 to 2009 is fully checked from mean distance error, distance error distribution, system error of the model, mean full-shift velocity error and the mode forecast error to circumstance fields by using T213L31 model of China National Meteorological Center. The analysis shows that the model forecast distance errors of 24,48, 72,96 hours forecasts are 135. 8, 250. 1, 376. 3, 515. 9 and 695.1 km. For the TC path of different alignment, the forecast for west path type is the best, followed by excrescent path and path of going up north. The biggest forecast error path is the path going up northeast, with the path east to change direction in second. Classifying the tropical cyclone strength indicates that the forecast error to tropical cyclone decreases as the strength increases, and the forecast is most efficient when the strength attains super typhoon. The forecast error to strong tropical storm is significant when forecast time increases, and the error to the tropical storm is also notable. The T213 produces a system deviation of northwest to west path among all average forecast samples. For northwest line and path to west cyclones the deviation is northeast to east and northeast to north. For cyclones changing direction to the northwest, middle, west and northeast, the deviation is northwest path, northwest to west and west system deviation respectively. But for the east changing direction and path going up north, the deviation is southwest to west and southwest respectively. Calculating the mean moving velocity,it's found that forecast for northeast path cyclones generates great error on initial velocity, reching up to 1.11 m/s, which leads to forecast error of distance. For the northwest, west, going up north type path cyclones the error of velocity is smaller, but for all changing direction type ones the velocity deviation is bigger. From the cases of T213 model which forecasts TC tracks with larger error in 2009 (such as No. 0904, No. 0906, No. 0907),by examining the model prediction error of the background field, it shows that the model overestimates westerly trough in middle and higher latitude regions. For forecasts of two close cyclones, the Fujiwhara Effect can happen easily, which will cause forecast deviation for TC tracks.%应用国家气象中心的T213L31模式对2006-2009年热带气旋路径数值预报的结果从平均距离误差、距离误差分布、模式系统性偏差、平均全移速误差、模式对背景场的预报偏差进行全面检验分析表明:对于不同走向的热带气旋(简称TC)路径预报而言,预报误差最小的是西行路径TC,预报误差最大的是东北行路径TC.按照TC强度进行分类统计发现,TC强度强比强度弱的路径预报平均距离误差小.T213对所有样本的平均预报而言,存在西北偏西向的系统性偏差,不同类型路径TC存在不同的系统性偏差.通过计算平均全移速可以看出,对于西北行、西行、北上类型路径在整个预报时效中移速偏差较小,而对于所有转向类路径移速偏差较大,即偏慢较明显.对T213模式预报2009年TC路径误差较大的个例(0904,0906,0907号热带气旋)检验模式对背景场的预报偏差,个例分析表明:模式对中高纬度西风槽预报偏强、对TC环境风场垂直切变预报偏大、对两个相近的TC预报更容易发生藤原效应,这些因素是导致TC路径偏差的主要原因.
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