摘要
Inthispaper,twosnowfallcasesunderdifferentweatherconditionsinnorthernChinaaresimulatedbyusingthemesoscalemodelMM5.Two-waynestingstructureofdomainsisdesignedforeachcase.AmongtheexplicitschemesofMM5,theReisnergraupelschemeisselectedtodescribethemicrophysicalprocess.Thesimulatedsnow-bandsoftwocasesarebasicallyconsistentwithobservations.Thesimulatedresultsofmicrophysicalprocessesaremainlydiscussed.Thehydrometeorsandtheirsourcesandsinksunderdifferentweatherbackgroundsaredescribed.Thefeedbackeffectsofmicrophysicalprocessesonthethermalanddynamicprocessesarealsodiscussed.Methodthatoutputstheaccumulativesourcesandsinksperhourisusedtoanalyzethedistributioncharacteristicsofhydrometeorsduringthestrongestsnowfallperiod.Twosensitivitytests(calledheattestanddragtest)areconductedtoexaminetheeffectsofmicrophysicalpro-cessesoncloudproducedbythelatentheatanddragforce.Resultshaveshownthatthedistributionofparticleshasacloserelationwithtemperature.Thetem-peratureofBeijingsnowfallisunder0℃andthereexistvaporandsolidphaseparticles,whileLiaoningsnowfallhasvapor,liquid,andsolidphaseparticlesduetothewarmtemperature.Thedistributionoftheseparticlesisnotthesameatdifferentdevelopmentstages.Fromtheanalysesofthecharacteristicsofsourcesandsinks,itisfoundthatsnowismainlyproducedbythedepositionandaccretionwithice.Cloudwateriscrucialtograupel.Themeltingofice-phaseparticlesenhancestherainproduction.Theresultsofheattestsanddragtestsrevealthatthemicrophysicalprocesseshaveinteractedwiththedynamicandthermalprocesses.Latentheatreleaseofhydrometeorsfeedsbackpositivelyonsnowfallwhilethedragforcenot.Atlast,comparisonsofsimulatedresultshavebeendonebetweenthetwodifferentkindsofsnowfallcases.ThemicrophysicalprocessesofLiaoningsnowfallcaseismorecomplicatedthanthoseofBe
出版日期
2007年04月14日(中国期刊网平台首次上网日期,不代表论文的发表时间)