川東夏季旱澇年天氣形勢(shì)轉(zhuǎn)換的數(shù)值診斷.pdf

1、中山大學(xué)碩士學(xué)位論文川東夏季旱澇年天氣形勢(shì)轉(zhuǎn)換的數(shù)值診斷姓名：吳珊珊申請(qǐng)學(xué)位級(jí)別：碩士專業(yè)：氣象學(xué)指導(dǎo)教師：袁卓建20090608ThenumericaldiagnosisoftheweathersituationtransitionofdroughtsandfloodsinEastofChuanYuareainsummerMajor：MeteorologyNante：WuShanshanSupervisor：ProfessorYuan

2、ZhuojianAbstractApplyingthegeopotentialheight(①)modelandNCEPreanalysisdatatoquantitativediagnosisthetransitionofgeopotentialheightfieldoftheeastofChuanYuareainJuly1722，1998(July612，2006)whenthedailyprecipitationchangedfr

3、omnOraintoheavyrain(frommoderateraintolightrain)Thediagnosticresultsshow硒follows：Inthecaseof1998，thevalleypointofthetotalcontributionofageostrophicprocessesto500hPa(ie①昭)appearedinJuly20withmaximumdailyprecipitation33mmw

4、hilethevalleypo硫ofthecontributionoftotalinternalforcesto500hPa一①(ieot。t。1)appearedinJuly23Theevolutionof’：①昭WaSmainlycausedbythehorizontalclosedcirculation(terms3and4)，theflowfieldofzonalverticalplanes(term7)andthediverg

5、enceoffrictionalforce(term17)InthecaSeof2006，thepeakvalueof①唱appearedinJuly7whilethepeakvalueof①t。t。lappearedinJuly12Theevolutionof中昭WaSmainlycausedbythezonaljetstream(term2)，thehorizontalsaddlecirculation(terms3and4)，th

6、eflowfieldofzonalverticalplanes(term7)andthehorizontaldivergenceoffrictionalforce(term17)Becausethegeostrophicdeviationalwaysdestroystheoriginalgeostrophicequilibriumstate，①昭willleadmtot。ltodecrease(increase)when①t。t。lis