基于微波辐射计的短时强降水潜势预报

微波辐射计可获取高时间分辨率的大气层结信息,为探索其在短时强降水预报方面的应用潜力,利用微波辐射计仪器获得对流参数特征,提取对短时强降水敏感的对流参数作为预报因子,并利用叠套法建立短时强降水潜势预报。结果表明:液态水路径LWP、SI、LI、CAPE、KOI这5种参数可作为预报因子建立潜势预报,经验证后得出短时强降水的POD、CSI、FAR分别为53.85%、50.01%、12.49%;另外,研究利用LWP的标准偏差在短时强降水发生前明显增大的特征改进预报,POD和CSI分别提升至73.08%、63.33%,FAR虽然增加至17.39%,但增量仅有4.9%。改进后的短时强降水预报效果提升明显,这说明水汽参数LWP在短时强降水预报中有较强的指示意义。

Research on Potential Forecasting of Short-range Precipitation Based on Microwave Radiometers

Radiometers can acquire information about atmospheric stratification with high temporal resolution.To study the potential capabilities of this information in forecasting short-range intense precipitation(hereafter referred to as"SRIP"),this work extracts convection parameters from microwave radiometers and uses those sensitive to SRIP as predictors.Then,the method of overlapping sets is used to formulate a procedure to forecast the potential of SRIP.The result is shown as follows.Five parameters,namely LWP(liquid water path),SI,LI,CAPE and KOI,can be used as predictors to forecast the potential of SRIP and their POD,CSI and FAR are verified to be 53.85%,50.01% and 12.49% respectively for the SRIP.Besides,the observation that the standard deviation of LWP increases substantially prior to the occurrence of SRIP is used to improve the forecast such that the POD and CSI are increased to 73.08% and 63.33% respectively,and FAR is increased to 17.39%(though with an increment of 4.9%).With the improvement,the forecasting of SRIP is much better,suggesting that the LWP is a good indicator in forecasting the SRIP.