热带气旋路径的模糊概率预报

FUZZY PROBABILITY FORECASTING METHOD FOR TROPICAL CYCLONE TRACKS

关键词:  热带气旋  路径类型  折向指数  模糊概率

Key words:  Tropical cyclone  Track types  Break index  Fuzzy probability

摘要:

根据南海及其附近区域热带气旋路径左、右折突变与持续稳定的类型预报判据,应用模糊数学原理,建立了路径变化类型模糊概率预报方法,此方法具有48小时的预报时效和预报路径突变或稳定的性能,还能给出预报轨迹的模糊概率,便于预报决策使用。业务试验表明,该方法操作简便、显示直观、客观定量、结论明确、效果良好。特别是当模糊概率大于70%时,方向误差和48小时平均距离误差都明显小于国内、外各主要预报台相应时次综合预报的误差,具有较高的参考价值。

Abstract:

Based on forecasting criteria of tropical cyclone track types: break(right/left turning) and steady tracks in the South China Sea and its nearby region, appling fuzzy mathematics principles,a fuzzy probability forecasting method for tropical cyclone tracks' change type was given in this paper. The method can be used to forecast whether a tropical cyclone's track will change or keep stable in 48 hours lead-time.Its forecasting output is in a fuzzy probability.Operational experiments with the method show that its forecasting output is objective, quantitative and definite,its running system is easy to operate,and the forecasting accuracy is good.Especially, when fuzzy probability is greater than 70%,errors of moving direction and 48 hours forecast are obviously smaller than those of subjective forecasts made by main weather stations. It is worthful of giving a reference to forecasting.