摘要
Characteristicsofthewavesources,energypropagationandconversionforanomalousRossbywaveactivities(RWAs)alongtheWestAsianjetstream(WAJS)insummerareexaminedbasedontheNCEP/NCAR(NationalCentersforEnvironmentalPrediction/NationalCenterforAtmosphericResearch)reanalysisdatafrom1958to2003,usingthevorticitysourceequation,theEliassen-Palm(EP)flux,andthewaveenergyequationunderdiabaticheating.ThestudyaimstofindthedynamicalcausesforRWAanomaliesalongtheWAJSandtoimprovetheunderstandingofmid-highlatitudecirculationanomalies.TheresultsshowthatthenegativevorticitysourceandthestrongEPfluxdivergenceovertheMediterraneanSeaandtheNorthAtlantic-ScandinavianPeninsulaareaactasthewavesourcesforRWAanomaliesalongtheWAJS.Whentheintensityandpositionofthewavesourcesareanomalous,theexcitedeastward-propagatingRWAalongtheWAJSalsobehavesanomalously.Instrong(weak)yearsofRWA,RossbywavesexcitedbythestrongdivergenceofEPfluxesovertheIceland-ScandinavianPeninsulaarea(easttotheScandinavianPeninsula)propagateeastwardandsoutheastward.Theeastwardpropagatingwavesbecomestrengthened(weakened)afterturningsoutheastwardneartheUralMountainsandthenenteringtheAsiansubtropicalwesterlyjetstream(ASWJS)overtheCaspianSea-AralSea-Xinjiang.Thesoutheastwardpropagatingwavesalsostrengthen(weaken)afterdirectlyenteringtheASWJSovertheeasternMediterranean-theBlackSea.Furthermore,thedivergenceofEPfluxesovertheMediterraneanalsostrengthens(weakens)inthestrong(weak)years,sotheyjointlybringaboutthestrong(weak)RWAalongtheWAJS.Finally,thepertur-bationavailablepotentialenergy(PAPE)alongtheWAJS(15°-60°E)producedbydiabaticheating,isfargreaterthantheconversionfromthekineticenergyofthebasicflowintotheperturbationkineticenergyandfromtheavailablepotentialenergyofthebasicflowintoPAPE.TheRWAalongtheWA
出版日期
2009年04月14日(中国Betway体育网页登陆平台首次上网日期,不代表论文的发表时间)