简介:Thelowlatitudeeasterliesat200hPainsummer(May-October)isanalysedclimaticallyduringthe13-yearperiodfrom1968to1980,withaspecialemphasisontherelationshipsbetweentheanomaloustropicaleasterlyjetStreamoverSouthAsiaandthelowlatitudeatmosphericcirculation,andalsothesummermonsoonprecipitationinIndia.ThecompositinganalysisshowsthatthetropicaleasterlyjetstreamoverSouthAsiahasfiveanomalouspatternsat200hPai.e.thewesternpattern,middlepattern,easternpattern,two-branchpatternandmulti-corepattern.EvidencehasshownthattheprecipitaioninIndiaanomalouslyincreasedduringtheanomalousperiodofthewesternpatternandthemiddlepattern,butreversecaseistrueintheeasternpattern.SomedifferentanomaliesoftheprecipitationindifferentareaofIndiawerefoundduringtheothertwoanomalouspattern.
简介:Thesynopticclimatologyofmonthlymeansurfaceairtemperatureanomaly(MMATA)at47surfacestationsinAsiaisassessedbytwotypesofmaps.ThefirstconsistsofsimplelinearcorrelationcoefficientsbetweentheMMATAatastationandthemonthlymean700hPaheightanomaly(MMHA)at134gridpointsintheNorthernHemisphere.Inwinter,thesefieldsgenerallycontaintwoequallyimportantcenters:acenterofmaximumpositivecorrelationapproximately1300kmfromthereferencestationandanegativecenterabout2800kmtoitsnorthwest.Insummer,thepositivecenterislocatedanaverageof800kmfromthereferencestationandstronglydominatestheMMATA,whilethenegativecenterisnolongerasimportantasinwinter.Thesecondkindofmapisaspecialtypeofanomalycomposite,constructedbymultiplyingthecorrelationcoefficientateachgridpointbythestandarddeviationofMMHAatthesamepoint.Thismapshowstheoptimumdistributionofheightanomaliesforabnormallywarm(orc
简介:BasedonthetheoryofCanonicalCorrelationAnalysis(CCA),thecorrelationbetween500hPageopotentialheight(H)fieldsovertheNorthernHemisphere(NH)anda15-regionrainfall(R)fieldofChinainMayisstudied.Theresultsindicatethat:(1)thereisastrongrelationshipbetweentheHfieldsinJanuary/MayandtheRfieldinChina,(2)thevariationofthegeneralcirculationoverthewholeNH(especiallythe500hPaHfieldoverEuropeandAsia)canaffecttheRinChina,(3)inJanuaryandFebruarytheatmosphericgeneralcirculationcanaffecttheRmainlybymeansofplanetarywaves,whileinAprilandMaythemaincontrolmechanismcanbeduetosometeleconnections,and(4)thecharacteristicvectorsforRinMayandHfromJanuarytoMayhavewavetrainstructure,alternatingsignfromsouthtonorth.
简介:用22年(1973~1994年)观测资料,由循环主振荡型分析(CSPOP)揭示了东半球500hPa环流、雪盖和中国降水量耦合系统的3~4年振荡的循环过程。结果表明,环流-冰雪-降水系统耦合振荡(ASRO)存在显著的欧亚太平洋(EUP)和中国东部型(EC)耦合移动波列,其中500hPa高度与雪盖波列空间位相相反,但一致向东南方向移动,而中国降水波列由北向南传播。这反映出欧亚雪盖异常影响欧亚大陆和海洋加热对比,并通过大气内部动力过程激发的耦合空间波的能量频散途径。
简介:Inthispaper,byusingspectralmethod,themonthly-andseasonal-scaleatmosphericdiabaticheatflow(ADHF)departurefieldsarediagnosedintheperiodof1964—1985with6ElNinoyearsand6anti-ElNinoyearsovertheNorthernhemisphere(NH).TheresultsshowthatElNinophenomenahavepronouncedinfluenceontheADHFdepar-turefields.Theresponseofatmosphereexhibitsapreferredarrangementoforganizingpositiveandnegativedeparturecentersatlow,middleandhighlatitudes.Inanti-ElNinoyears,theresponsehasthesameformsasinElNinoyears,butdeparturecentersareoppositeinphase.Furthermore,ADHFdepartureshowslow-frequencyoscillationinElNinoyearsandanti-ElNinoyears.ThecenterofdifferenceindeparturebetweenElNinoandanti-ElNinoyearsdisplaysabi-monthlyoscillation.Finally,throughair-seacorrelationanalysis,itispointedoutthattheSSTanomalyisthemostimportantcauseforADHFanomaly.
简介:利用40a(1961—2000年)的海温资料和同期NCEP资料以及高原51个测站的降水资料,探讨了赤道东太平洋平均海温增暖与青藏高原东部地区500hPa月平均高度的相关关系,以及在这种相关影响下气温、比湿和气流动能等的变化状态。结果表明:赤道东太平洋海温增暖(SSTA≥0.5℃)与青藏高原东部地区500hPa月平均高度场之间存在明显的滞后性相关关系,这种滞后性相关不但影响到高原高度场,还影响到气温、比湿和气流动能等,使高原500hPa气象场发生变化。同时这种变化又与高原东部地区表征旱涝状况的Z指数的时空分布有很好的对应关系,即当受影响的高度、气温、比湿增大及气流动能减小时,高原东部地区发生涝(多雨)的几率较大;当受影响的高度、气温、比湿减小及气流动能增大时,高原东部地区发生旱(少雨)的几率较大。
简介:本研究的目的是分析人类血小板抗原(humanplateletantigen,HPA)基因多态性,根据分布频率来判断HPA抗原不配合比率以及抗体产生的机会,确定有临床意义的血小板抗原系统,并建立邯郸地区血小板基因频率数据库和供者库.采用SSP-PCR方法对邯郸地区148名随机献血者进行HPA1-16抗原32个等位基因的检测分析,并与不同人群的分布频率进行比较.结果表明:每个样本均检测到HPA-1a、2a、4a-14a、16a基因;HPA-4a、7a-14a、16a呈现单态性,未检测出相应的等位基因HPA-b;对于HPA-1、-2、-5、-6主要以a/a纯合子为多,a/a基因型频率分别是0.9595、0.8108、0.9865、0.9797,没有b/b纯合子出现.在HPA1-16中,具有最高杂合度的是HPA-15,基因型HPA15a/15a、HPA15a/15b、HPA15b/15b频率分别是0.2230、0.5270、0.2500;HPA-3在其次,基因型HPA3a/3a、HPA3a/3b、HPA3b/3b频率分别是0.3851、0.5135、0.1014.经x2检验,结果符合Hardy-Weinberg遗传平衡定律.邯郸地区随机献血者HPA1-5系统基因频率与石家庄地区相似(P>0.05);与我国台湾人群进行HPA1-13、HPA-15的比较,HPA-1、-2、-6具有明显的不同(P<0.05),其它相似(P>0.05);与韩国人群进行HPA1-8的比较,除HPA-3具有明显不同外(P<0.05),其余均相似(P>0.05);与美国黑人进行HPA1-5的比较,HPA-1、-2、-5具有明显的差异(P<0.05);与英国人进行HPA1-11的比较,HPA-1、-5具有明显的不同(P<0.05).结论:北方地区中国人群HPA-2、-3、5、-15系统具有多态性,且HPA抗原分布不配合比率较高,这必然造成免疫暴露的机会增加,提示在临床上可能具有重要的免疫学意义.同时,在此次研究数据的基础上建立了邯郸地区血小板基因频率数据库和血小板已知型供者库.