Application of the Year-to-Year Increment Approach in Precipitation Prediction During Flood Season in Chongqing
Zheng Yingfei
Wu Yao
Tang Hongyu
Guo Qu
Fan Guangzhou
Abstract：Based on the precipitation data from 34 meteorological stations in Chongqing,NCEP/NCAR reanalysis data,and CFSv2 model products,this article investigates the spatio-temporal distribu-tion characteristics of precipitation during the flood season(May-September)and the atmospheric circu-lation patterns of typical anomalous precipitation years.Significant differences are identified in drought/flood-sensitive regions and key atmospheric circulation features influencing precipitation in these months.Consequently,monthly-specific statistical downscaling prediction models are established for precipitation prediction at the 34 stations in Chongqing during the flood season from May to September.These models incorporate the key precursor and concurrent predictors selected by the year-to-year increment approach.the average Ps score of the downscaling models from May to September in 2012-2020 can reach 74.2,representing a 13.1-point improvement over direct CFSv2 model outputs.This highlights the advantages of the downscaling models in predicting precipitation during the flood season in Chongqing.Furthermore,the downscaling models can basically predict the relatively high-value and low-value precipitation zones in both anomalously dry and wet years,thereby demonstrating a robust skill in reproducing regional distribu-tion characteristics of precipitation.
Keywords：the year-to-year increment approachflood season precipitationClimate Forecast Sys-tem version 2(CFSv2)
Publication Date：2025-07-30
Online Publishing Date：2026-09-12(First online date of this platform, not the publication date of the document)
Pages：8( 97-104 )