Monitoring and Early Warning Indicators of Short-Term Rainstorm Processes Based on FY-4A Satellite Data
The short-time rainstorm caused by small and mesoscale weather systems,which has characteristics such as short duration and strong disaster potential.The short-time rainstorms are always the focus of meteorological research and the challenge in weather forecasting.Currently,FY-4A satellite products have a few applications in research and service,especially in the analysis of short-term rainstorms.The application and analysis of satellite cloud images in weather reports are still mainly based on judgment and qualitative extrapolation,lacking quantitative proximity prediction indicators of short-term rainstorms.Based on FY-4A satellite product data and ground precipitation observation data from 2018 to 2021,we study the analysis of short-term rainstorm weather processes in the flood season,which occurs from May to September in Ningxia.By using correlation analysis,box-plot and extreme value statistics methods,we evaluate the monitoring and early warning indicators of FY-4A satellite products in the weather process of short-term rainstorms.The results show that:(1)FY-4A satellite data can serve as not only qualitative indicators but also quantitative indicators for short-term rainstorms monitoring and early warning after processing with methods such as correlation analysis,box plot,and extreme value statistics.(2)Thirteen products of the FY-4A satellite have a good correlation with the sample sequence of short-term heavy precipitation,including Black Body Temperature(TBB),Convective Inception(CIX),Cloud Mask(CLM),Cloud Phase(CLP),Cloud Type(CLT),Cloud Top Height(CTH),Cloud Top Pressure(CTP),Cloud Top Temperature(CTT),Total Precipitable Water(TPW),Quantitative Rainfall Rate Estimation(QPE),Cloud Effective Radius(CER),Cloud Liquid Water Path(LWP)and Tropopause Folding Uppermost Height(TZD),which can serve as monitoring and early warning indicators.We set the criteria that short-term heavy rainfall will occur when nine out of thirteen product indicators meet the standards,which can be optimized and adjusted through operational practices.(3)Among the thirteen products,there are four key indicators,which are Convective Inception(CIX),Cloud Mask(CLM),Cloud Phase(CLP),and Cloud Type(CLT),and three auxiliary indicators,which are Cloud Top Height(CTH),Cloud Effective Radius(CER),and Cloud Liquid Water Path(LWP),while the other products are numerical discriminant indicators.(4)After improvement based on the evaluation,the True Skill Statistic(TS)increases by 5.4％,the false reporting rate decreases by 2.7％,and the miss reporting rate decreases by 1.9％.The study of monitoring and early warning indicators using FY-4A satellite multi-channel product data is an experimental trial and has great application value,especially in the application of quantitative indicators to intelligent discrimination and automatic alarm.This study holds significant importance for improving the early warning recognition and advance warning capabilities of short-term heavy precipitation.
FY-4A Satelliteshort-term rainstormmonitoring and warning indicatorstest
NETL
NSTL
万方数据
