近60年來赤道印度洋—太平洋緯向環(huán)流變化特征.pdf

1、南京信息工程大學(xué)碩士學(xué)位論文近60年來赤道印度洋—太平洋緯向環(huán)流變化特征姓名：李聰申請學(xué)位級別：碩士專業(yè)：氣象學(xué)指導(dǎo)教師：肖子牛20100401Abs仃actThecharacteristicsoftheequatorialPacificWalkercirculationOVerthepast60yearsaleanalyzedbyusingthemeteorologicaldataofSurfaceLevelPressure(SLP)

2、、500hPaVerticalVelocity@)、200hPaVelocityPotential()()andOutgoingLongwaveRadiation(OLR)，eta1TheNCEP／NCARwindfielddatasetandzonalmassfluxfunctionhavealsobeeninvestigatedforevidenceofzonalverticalcirculationalongtheIndianOc

3、eanequatoranditsroleinclimaticvariabilityTheresultsshowthattheEarth’Ssurfacehaswarmedsincethemid_nineteenthcenturytheobservedzonalSSTgradientalongtheequatorpreferan‘E1Nifio。like’warminginthelast60years(waringmoreintheeas

4、tthaninthewest)ObservedweakenoftheSLPgradientisallintrinsiccharacteristicofthetropicalatmosphereinawarmerclimate，thesizeofthistrendisconsistentwiththeoreticalpredictionsTheWalkerCirculationcompriseseastwestatmosphericcir

5、culationcellsalongtheequatorialbeltThePacificbranchoftheWalkerCirculationconsistsofeasterlywindsatthelowertroposphere，westerlywindsattheuppertroposphere，risingmotionOVerthewesternPacific，andsubsidenceovertheeasternPacifi

6、cThisCirculationischaracterizedbyapronouncedseasonalcycleandinterannualvariabilityandisanintegralcomponentoftheE1NifioSouthernOscillationclimatesystemFluctuationsoftheWalkerCirculationCanleadtoextremeweatherconditionsind

7、ifferentpartsoftheworldTimeseriesoftheintensityoftheWalkercirculationwhicharedefinedby500hPaCO，200hPa)CandOLR，coincidewitlltheSouthernOscillationindex(SOD，andtheCellhasweakenedinrecentdecadesThewesternupwelling、easterndo