关键词: GRAPES_TYM, 热带气旋, 降水评估, 降水订正

Abstract:

he precipitation forecast of tropical cyclone (TC) landing in South China during 2012-2013 from the pattern matching capability, the average precipitation and extreme precipitation by GRAPES_TYM model was synthetically assessed. And on this basis that the interpretation methods of precipitation forecast for TC influencing Hainan Island were established and tested. The results show that the comprehensive evaluation index of ETS score and spatial correlation coefficient between the observed and forecasted precipitation by GRAPES_TYM model for TC landing in South China was 0.31, and the value depended on the deviation of TC path prediction by the model. The comprehensive assessment index of average precipitation forecast was 0.76. Thereinto, the error index showed that the forecasted median of average precipitation within the influence of TC was less than 3.6 mm of the observation,  and the forecasted values of average precipitation in rain belts with different distances from the centre of TC were smaller than the observation, the forecasted precipitation in outer rain belt was better than that in inner rain belt. To the extreme precipitation assessment, the threshold of extreme precipitation within 100 km distance from the centre of TC was closed to the observation, while that in the rest of rain belts was smaller than the observation. As for Hainan Island, the interpretation method of TC precipitation predicted by GRAPES_TYM model was consistent of TC path correction, rain belts translation and topographic correction, and the corrected TS scores of moderate rain, heavy rain and rainstorm by the interpretation method of TC during 2012-2013 improved significantly, especially for rainstorm, increased by 9.9% compared with that before the correction.

Key words: GRAPES_TYM, tropical cyclone, precipitation assessment, precipitation correction