2020年西北太平洋和南海台风预报精度评定

Verification on Forecasts of Typhoons over Western North Pacific and South China Sea in 2020

对2020年西北太平洋和南海海域23个编号台风的定位定强精度以及路径、强度、登陆点预报精度进行了评定。评定结果表明:2020年,中央气象台的平均定位误差为22.7 km,平均定强误差为1.3 m·s^(-1),与2019年相比定位误差略偏大,定强误差则略偏小。自2013年以来,72 h以内的主观和客观台风路径预报性能并没有实质性改进,并且到了2020年,路径预报误差极端偏大样本的误差平均值却仍能达到年平均误差的2.3~3.0倍。中央气象台在72 h以内的强度预报性能位居所有官方台风预报机构的前列。2020年各预报方法较成功地预报出了热带风暴鹦鹉在广东阳江海陵岛的登陆点,部分模式也精准预报出了强台风黑格比在浙江乐清以及强热带风暴浪卡在海南琼海的24 h登陆点。

Operational positioning and intensity estimation errors,track,intensity and landfall point forecast errors of 23 named typhoons over Western North Pacific and South China Sea in 2020 are evaluated in this paper.The verification results show that the total average positioning and intensity estimation errors of National Meteorological Centre(NMC),CMA,were 22.7 km and 1.3 m·s^(-1),respectively.Compared to the estimation in 2019,the value of positioning error was slightly larger than in 2019,but the intensity estimation error was a little bit smaller than in 2019.Since 2013,the overall track forecast performance within 72 h has not shown substantive improvement for both subjective and objective forecast methods.Moreover by 2020,the mean values of extreme large track error cases were still up to 2.3-3.0 times compared with their annual mean track errors,but the intensity forecast performance of NMC/CMA within 72 h was better than that of the other official typhoon forecast agencies.In 2020,the landfall point of tropical Storm Nuri at Hailing Island,Yangjiang City,Guangdong Province was successfully predicted by all the official typhoon forecast agencies and some models also accurately forecasted in 24 h advance the Severe Typhoon Hagupit and Severe Tropical Storm Nangka’s landfall points in Yueqing City,Zhejiang Province and Qionghai City,Hainan Province,respectively.