冬季歐亞積雪異常對北太平洋風(fēng)暴軸的可能影響.pdf

1、南京信息工程大學(xué)碩士學(xué)位論文冬季歐亞積雪異常對北太平洋風(fēng)暴軸的可能影響姓名：趙蔚申請學(xué)位級別：碩士專業(yè)：氣象學(xué)指導(dǎo)教師：朱偉軍20070501PossibleEffectsofEurasianSnowAnomalyonNorthernPacificStormTrackDudngWinterAbstractByusingtheobservationdataforthedepthofperpetualsnowEurasiansnowarea

2、indexinwinteriselucidatedItwasfoandthattheareaofEurasiansnOWnotonlyhaveasignificantinterannualchangebutalsobeinggraduallyshrinkinginwinterduringtheperiodfiom1980to2002Thesnowywinters舾wellassnowlesswintersOVerEurasiancont

3、inentarepickedoutonthebasisoftheindexfortheareaofEurasiansnowTheeffectsofEurasiansnowanomalyonthenorthPacificstormtrackisstudiedthroughsingularvaluedecomposition(SVD)，correlationanalysisandcompositeanalysison23winters’50

4、0hPafilteredgeopotentialheightvarianceOVerthenorthPacificstormtrackandEurasiansnowItillustratesthatthepositiveanomalyofEurasiansnowareaanomalyisassociated稍吐lthesouthwardshiRingofPacificstormtrackandtheintensitydecreaseof

5、thestormtrackcenterViceversaThepossiblephysicalprocessoftheinfluencethatEurasiansnowexerts011thenorthPacificstormtrackisstudiedthroughtheftlrlhcrcompositeanalysisTheresultsindicatethatwhentheEurasiansnowareaisabnormallyl

6、arge，coolingeffectbecomestrongerwhichleadstothenoticeabledecreaseofupperairtemperatureandsubsequentheightdepressoverEurasiancontinentandPacificOCeanThenbeyondthoseregionthetemperatureandpressuregradientchang：decreaseinth

7、emidandhighlatitudeandincreaseinthelowlatitudeTherefore，ononehand，themeridionalheattransportationandthewindbecomeweakerinthemidandhi。業(yè)latitude，ontheotherhand，theybecomestrongerinthelowlatitudeThenjetstreammovessouthwarda

8、nditsintensitydecreaseinthemid—andhighlatitudeandincreaseinthelowlatitudeSothedevelopmentofbaroclinicwaveisrestrainedinthemidandhighlatitudeThen，thebaroclinicityintheupstreamofthestormtracktobeweakerandtheenergyofbarocli