简介:
简介:Inthecontextofglobalwarming,Chinaisfacingwithincreasingclimaterisks.Itisimperativetodevelopquantitativeindicestoreflecttheclimateriskscausedbyextremeweather/climateeventsandadverseclimaticconditionsinassociationwithdifferentindustries.Basedontheobservationsat2288meteorologicalstationsinChinaandthemeteorologicaldisastersdata,asetofindicesaredevelopedtomeasureclimaterisksduetowater-logging,drought,hightemperature,cryogenicfreezing,andtyphoon.Astatisticalmethodisthenusedtoconstructanoverallclimateriskindex(CRI)forChinafromtheseindividualindices.Thereisagoodcorrespondencebetweentheseindicesandhistoricalclimaticconditions.TheCRI,theindexofwater-loggingbyrain,andthehightemperatureindexincreaseatarateof0.28,0.37,and0.65perdecade,respectively,from1961to2016.Thecryogenicfreezingindexiscloselyrelatedtochangesintheconsumerpriceindexforfood.Thehightemperatureindexiscorrelatedwiththeconsumptionofenergyandelectricity.Thecorrelationbetweentheyearlygrowthinclaimsonhouseholdpropertyinsuranceandthesumofthewater-loggingindexandthetyphoonindexinthesameyearisashighas0.70.BoththegrowthrateofclaimsonagriculturalinsuranceandtheannualgrowthrateofhospitalinpatientsarepositivelycorrelatedwiththeCRI.Theyear-on-yeargrowthinthenumberofdomestictouristsissignificantlynegativelycorrelatedwiththeCRIinthesameyear.MoreeffortsareneededtodevelopregionalCRIs.
简介:MM5,它是PSU/NCAR中央放大非静水力学的有限区域的模型,并且它毗连当模特儿的系统在这篇论文被使用。由使用二假数据吸收的台风的一个最佳的起始的条件策划的作者产生的背景回答的拿的T106分析数据,和某数字模仿试验的行为。No.9608typhoon(葛洛丽亚)的结果证明最佳的起始的地有一些戏剧的改进,例如台风中心,更弱的台风发行量和台风的不完全的内部结构的不精密的位置,它被数据的缺乏在海上引起。一些改进在轨道预报被做了。通过几个比较实验,BDAscheme优化的初始化比GFDL计划和它的台风路经预报更好被发现更合理。
简介:PreliminaryresultsofthewindvelocityestimationusingtheMaximumEntropyMethod(MEM)toMUradarobservationdatasetsarepresented.ThecomparisonoftheresultsfromtheperiodogrammethodandtheMEMshowsthattheMEMestimationisreliable,andhashigheraccuracy,resolutionanddetectabilitythantheestimationfromperiodogrammethod.ThehighaccuracypowerspectrumobtainedbytheMEMisveryusefultostudyingtheatmosphericturbulencestructure.However.theMEMneedsthelongercomputingtimeforobtainingthehighaccuracyspectrum.Particularly,theestimationofMEMwillbringseriousdevia-tionatlowersignal-to-noiseratio.
简介:半含蓄的算法流行地被用来在数字模型处理重力的术语。在这份报纸,我们采用特征的方法在一个浅水模型用一个semi-Lagrangian移流计划直接在一个范围上为严肃波浪计算答案而不是半含蓄的方法,到避免昂贵的矩阵倒置。semi-Lagrangian计划的采纳为任何报纸数字使数字模型变为总是稳定,并且它节省中央处理器时间。为了说明特征的效率,抑制了插值侧面(CIP)方法,一些数字结果在Yin-Yang格子系统在一个范围上为理想化的测试用例被显示出。关键词特征CIP方法-浅水的模型-Yin-Yang格子-semi-Lagrangian计划-严肃波浪
简介:Toimprovetheaccuracyofnowcasting,anewextrapolationtechniquecalledparticlefilterblendingwasconfiguredinthisstudyandappliedtoexperimentalnowcasting.Radarechoextrapolationwasperformedbyusingtheradarmosaicatanaltitudeof2.5kmobtainedfromtheradarimagesof12S-bandradarsinGuangdongProvince,China.Thefirstbilateralfilterwasappliedinthequalitycontroloftheradardata;anopticalflowmethodbasedontheLucas–KanadealgorithmandtheHarriscornerdetectionalgorithmwereusedtotrackradarechoesandretrievetheechomotionvectors;then,themotionvectorswereblendedwiththeparticlefilterblendingalgorithmtoestimatetheoptimalmotionvectorofthetrueechomotions;finally,semi-Lagrangianextrapolationwasusedforradarechoextrapolationbasedontheobtainedmotionvectorfield.Acomparativestudyoftheextrapolatedforecastsoffourprecipitationeventsin2016inGuangdongwasconducted.Theresultsindicatethattheparticlefilterblendingalgorithmcouldrealisticallyreproducethespatialpattern,echointensity,andecholocationat30-and60-minforecastleadtimes.Theforecastsagreedwellwithobservations,andtheresultswereofoperationalsignificance.Quantitativeevaluationoftheforecastsindicatesthattheparticlefilterblendingalgorithmperformedbetterthanthecross-correlationmethodandtheopticalflowmethod.Therefore,theparticlefilterblendingmethodisprovedtobesuperiortothetraditionalforecastingmethodsanditcanbeusedtoenhancetheabilityofnowcastinginoperationalweatherforecasts.
简介:在生气增加形式的动量移流涡度方程被介绍,在哪个在经典涡度方程的分叉术语不明确地出现。这个方程包括水平风移流的旋转效果,它明确地没在经典涡度方程被包括。涡度和它发生在2008年7月的台风Fung-Wong(0808)的趋势被分析。计算结果证明水平风的移流的旋转效果是在在它的生命周期期间为Fung-Wong决定垂直涡度的变化的一个领先的因素,特别在乍见陆地导致的时期。移流学期代表垂直涡度的趋势变化,并且垂直涡度趋势的积极值的区域几乎与Fung-Wong的轨道一致,它可以作为一个因素被拿定位Fung-Wong的关键观察区域。方程为与水平风的强壮的移流联系的系统提供一个增补诊断工具。
简介:Usingequivalentblackbodytemperature(TBB)dataretrievedfrommeteorologicalsatelliteGMS-5during1996-2002,thecorrelationbetweenthecircularsymmetric/asymmetriccomponentofTBBandtheintensityoftropicalcyclone(TC)atvarioustimelagsfrom0to48hisanalyzedfortheNorthwestPacific(0°-50°N,120°-155°E),excludinglandedandnear-coastsamples.ItisfoundthatthetotalTBBnearsoutheastoftheeyewall,thecircularsymmetriccomponent,andthesumoftheamplitudesoftangentialwavenumbers1-10(SA10)oftheTBBbetweentheradiiof0.8°and1.7°aresignificantlyandnegativelycorrelatedwiththeTCintensityatvarioustimelagsfrom0to48h.Especially,themaximum24-hlagcorrelationcoefficientsreach-0.52,-0.58,and-0.625,respectively.AstatisticalpredictionschemeforTCintensityisdevelopedbasedonclimaticpersistent,synoptic,andTBBfactorsbystepwiseregressiontechnique.ItisfoundthatthevariancecontributionoftheaveragedTBBovertheringbetween1.0°and1.5°fromtheTCcenterranksthefourthintheequationfor12-hTCintensityprediction,andthoseofthetotalTBBnearsoutheastoftheeyewallandthedifferencebetweenmaximumandminimumTBBbetween1.1°and1.5°rankthethirdandfifthrespectivelyinthe24-hforecastequation.Itisalsoshownthat,withTBBfactors,thefollowingpredictionsareimprovedcomparedtotheschemewithoutTBBfactors:48-hpredictionforseveretropicalstorm(STS),12-hpredictionforTCwithaweakeningrategreaterthan15ms~(-1)/12h,24-hintensitypredictionforTCwithalmostnointensitychange,and48-hpredictionforTCintensifyingfasterthan10ms~(-1)/48h.
简介:在Lorenz系统的一个类似物动态的模型(ADM)的理论基础和申请被学习。ADM能有效地联合状态能被认为是一个预言目的当前的起始的值的小骚乱在历史的类似物引用上在附加了的统计、动态的方法。主要分析证明在在模型参数添加骚乱的条件下面,ADM的模型错误是比纯动态模型(PDM)的那些小得多的。在Lorenz系统的ADM上的可预测性的特征被进行案例研究和全球实验在阶段空间分析。结果证明ADM罐头相当有效地减少预言错误并且与PDM相对照处于大多数状况延长预言的有效时间,但是当模型错误是更加小的时,后者将比前者优异。克服如此的一个问题,更新的multi-reference-state能被使用介绍多类似物和更改类似物的信息并且能在ADM展出令人激动的性能。
简介:TheElNino-SouthernOscillation(ENSO)reflectsanomalousvariationsintheseasurfacetemperature(SST)andatmosphericcirculationoverthetropicalcentral-easternPacific.Itremarkablyimpactsonweatherandclimateworldwide,somonitoringandpredictionofENSOdrawintensiveresearch.However,thereisnotyetauniquestandardinternationallyforidentifyingthetiming,intensity,andtypeofENSOevents.TheNationalClimateCenterofChinaMeteorologicalAdministration(NCC/CMA)hasledtheefforttoestablishanationalidentificationstandardofENSOevents,whichwasofficiallyendorsedbytheNationalStandardizationAdministrationofChinaandimplementedoperationallyinNCC/CMAin2017.Inthispaper,twokeyaspectsofthisstandardareintroduced.First,theNino3.4SSTanomalyindex,whichiswell-recognizedintheinternationalENSOresearchcommunityandusedoperationallyintheUS,hasreplacedthepreviousNinoZindexandbeenusedtoidentifythestart,end,andpeaktimes,andintensityofENSOevents.Second,twonewindices-theeasternPacificENSO(EP)indexandthecentralPacificENSO(CP)index,basedontheSSTconditionsinNino3andNino4regionrespectively,arecalculatedtofirstdeterminetheENSOtypebeforemonitoringandassessingtheimpactsofENSOonChina’sclimate.Withthisstandard,allhistoricalENSOeventssince1950areconsistentlyre-identified;theirdistinctpropertiesarediagnosedandpresented;andtheimpactsofENSOeventsunderdifferenttypesonChina’sclimatearere-assessed.Thisstandardisalsoemployedtovalidatetheintensity,grade,andtypeoftheENSOeventspredictedbytheNCC/CMAoperationalENSOpredictionsystem.Thenewstandardandthethusderivedunifiedsetofre-analyzedhistoricalENSOeventsandassociatedinformationprovideagoodreferenceforbettermonitoringandpredictionoffutureENSOevents.
简介:许多有缺点的雷达回响可以用雷达数据应用,特别雷达数据吸收和量的降水估计引起严重问题。在这研究,测试模式在CINRAD(中国新一代天气雷达)由测试信号或雷达硬件失败引起了SA和SB雷达运作的观察被调查。为了把测试模式与雷达回响的另外的类型区分开来,例如降水,清除空气和另外的非气象学的回响,包括有效反射率数据百分比(RZ)的五个特征参数,速度RF(合拢的范围)数据百分比(RRF),失踪的速度数据百分比(RM),平均沿着方位角反射率变化$\left({R_{N_{r,Z}}}\right)$并且平均沿着横梁反射率变化$\left({R_{N_{一,Z}}}\right)$被建议。基于模糊逻辑方法,一个测试模式鉴定算法被开发,并且从雷达回响的所有不同类型的统计结果显示算法的表演。有在测试模式内定位的重降水回响的二个典型箱子的分析被执行。统计结果证明测试模式鉴定算法表现很好,自从测试模式在大多数情况中被认出。而且,算法能有效地移开测试模式信号并且在重降雨事件保留强壮的降水回响。
简介:UsingNCEPreanalysisdataandanairflowtrajectorymodelbasedontheLagrangianmethod,theHybridSingle-ParticleLagrangianIntegratedTrajectory(HYSPLIT)model,thedailybackwardtrajectoriesontheheightof850hPaabovetheSouthChinaSea(SCS)areaaresimulatedfromApriltoJune.TheonsetdateoftheSCSsummermonsoonfrom1948to2009isdeterminedaccordingtothesimulatedsourceofairflowinthemonitoredareaoftheSCS.ByanalyzingtheSCSmonsoononsetdatesoverthe62years,wefoundthatthenumberofyearsinwhichtheSCSmonsoononsetisearlieraccountsfor13%,andthelateryears14%,thenormalyears73%,ofallthe62years.AnalyseswiththeLagrangianmethod,doneincomparisonwiththeothertwomethodswhichcombinewindandpotentialpseudo-equivalenttemperature,wereperformedtodeterminetheonsetdatesoftheSCSsummermonsoon.Insomeyears,thesourceofthesouthwestairflowinthemonitoredareaoftheSCSisinthesubtropicalregionbeforetheonsetoftheSCSmonsoon,sotheairflowfromthesubtropicscanbedistinguishedwiththeairflowfromthetropicsbyusingtheLagrangianmethod.Thesimulationbythetrajectorymodelindicatedthatinsomeyears,aftertheonsetofSCSsummermonsoon,theSCSwillbecontrolledbythesoutheastwindinsteadofthesouthwesterlyusuallyexpected.
简介:这份报纸测试在与奔流的雨联系的异例由使用第五产生的NCAR/佩恩状态Mesoscale模型(MM5)输出的好模型模拟数据由台风No.9914(丹)引起了的潮湿的潜在的涡度(MPV)上强迫的导致云的质量的影响。诊断结果证明积极MPV异例区域,它被从600hPa集成MPV到300hPa在获得垂直,粗略地在位置或在分发模式在他们的同步阶段与降水与一致,并且丹的最大的积极MPV区域主要在600hPa和300hPa之间被定位,它比奔流的雨盒子高得多。进一步的分析也证明积极MPV异例的值与丹的开发增加了或减少,并且积极MPV异例可以也作为tracer被服务显示热带气旋紧张的进化。
简介:许多观察研究证明了那变丑象垂直涡度和分叉一样,是仔细与强壮的降水的出现和分发有关。在这份报纸,在降水诊断包含变丑,称为潜在的变丑(PD)的一个新参数被导出然后在模仿的mesoscale以内适用于降水察觉对流系统(MCS)。PD包括拉长变丑和砍的变丑的两个并且当它不随着旋转坐标变化,到这个程度与变丑分享类似的特征,这被显示出。模仿的MCS的诊断表明PD表现很好在跟踪MCS降水。以他们的分布模式,PD的大值的区域类似于在MCS的不同发展阶段的降水。在PD以内包含的物理过程的详细分析证明它能反映三维的潮湿变化,垂直的风砍并且在MCS以内弯屈变丑。这些结构通常是在猛抛以内的表面寒冷水池,后面的流入喷气,向下冷的空气流动和向上温暖的潮湿的流动的特征的全面思考对流房间。为这个原因,PD比非猛抛的空气在猛抛的空气显示出强壮得多的异例,它在在MCS以内检测重降水为它的申请暗示可观的潜力。
简介:大气红外线更健全(表情)在水卫星上的仪器是高光谱分辨率infrared更健全。在最近的年里,表情逐渐地成为了大气的垂直观察的主要方法。在中国上检验表情检索产品(V3.0)的确认,表情表面气温检索与分别地在2004年7月和2005年1月从540个气象学的车站获得的扎根的观察相比。错误的来源更加被讨论。基于错误分析,检索的表情出现气温产品systemi-cally被改正。而且,表情温度和湿度侧面检索与T213相比数字预报产品。因为T213forecasting产品不是实际大气的状态,侧面产品通过用肘轻推的分析被吸收进一步验证确认,表情温度和湿度进MM5模型。在这篇论文,盒子在2005年2月14日详细在诺思中国被模仿。然后,我们在降雪,湿度地,垂直速度地,分叉地,和云上调查了表情检索的效果微物理过程。主要结果是:(1)检索的表情的错误出现气温产品大部分是系统的偏差,地面高度的影响和表面类型为是主要原因;(2)表情大气的侧面检索和T213之间的差别在温度的数字预言产品通常是不到2K,在相对湿度的差别通常是不到25%;并且(3)表情温度和湿度检索产品能调整模型起始回答,并且能因此改进降雪模拟的能力到某程度。
简介:Aheavyrainfallprocess,whichoccurredinShanghaiduring5-6August,2001fromalandfallingtropicaldepression(TD),isexaminedwithacontrolnumericalexperimentbasedonMM5model.Itisfoundthatthecontoursofgeneralizedequivalentpotentialtemperature(θ*)arealmostverticalwithrespecttohorizontalsurfacesneartheTDcenterandmoredenselydistributedthanthoseofequivalentpotentialtemperature(θe).Becausetheatmosphereisnon-uniformlysaturatedinreality,θ*takestheplaceofθeinthedefinitionofconvectivevorticityvector(CVV)sothatanewvector,namelythegeneralizedconvectivevorticityvector(CVV*),isappliedinthisstudy.SinceCVV*canreflectboththesecondarycirculationandthevariationofhorizontalmoistbaroclinicity,theverticalintegrationofverticalcomponentofCVV*isfound,inthisstudy,torepresenttherainfallareasintheTDcasebetterthanpotentialvorticity(PV),moistpotentialvorticity(MPV),generalizedmoistpotentialvorticity(Pm),andCVV,withhigh-valueareaofCVV*correspondingtoheavy-rainfallarea.Moreover,theanalysisfromCVV*impliesthattheHangzhouBaymightplayanimportantroleintheheavyrainprocess.AsensitivityexperimentwithouttheHangzhouBayisthendesignedandcomparedwiththecontrolrun.ItisfoundthattheCVV*becomesweakerthanthatinthecontrolrun,implyingthattheeliminationofHangzhouBayresultsinreducedrainfall.FurtheranalysesshowthattheHangzhouBayprovidessufficientwatervaporandsurfaceheatfluxtotheTDsystem,whichisveryimportanttothegenesisanddevelopmentofmesoscalecloudclustersaroundtheTDandtheassociatedheavyrainfall.
简介:Cloudmicrophysicalpropertyretrievalsfromtheactivemicrowaveinstrumentonasatelliterequiretheclouddropletsizedistributionobtainedfromaircraftobservationsasaprioridataintheiterationprocedure.Thecloudlognormalsizedistributionsderivedfrom12flightsoverBeijing,China,in2008–09werecharacterizedtoevaluateandimproveregionalCloudSatcloudwatercontentretrievals.Wepresentthedistributionparametersofstratiformclouddroplet(diameter<500μmand<1500μm)anddiscusstheeffectoflargeparticlesondistributionparameterfitting.Basedonthreeretrievalschemeswithdifferentlognormalsizedistributionparameters,theverticaldistributionofcloudliquidandicewatercontentwerederivedandthencomparedwiththeaircraftobservations.Theresultsshowedthattheliquidwatercontent(LWC)retrievalsfromlargeparticlesizedistributionsweremoreconsistentwiththeverticaldistributionofcloudwatercontentprofilesderivedfrominsitudataon25September2006.WethenappliedtwoschemeswithdifferentaprioridataderivedfromflightdatatoCloudSatoverpassesinnorthernChinaduringApril–Octoberin2008and2009.TheCloudSatcloudwaterpath(CWP)retrievalswerecomparedwithModerateResolutionImagingSpectroradiometer(MODIS)liquidwaterpath(LWP)data.TheresultsindicatedthatconsideringaprioridataincludinglargeparticlesizeinformationcansignificantlyimprovetheconsistencybetweentheCloudSatCWPandMODISCWP.Theseresultsstronglysuggestthatitisnecessarytoconsiderparticleswithdiametersgreaterthan50μminCloudSatLWCretrievals.
简介:追踪作为多尺度知道的算法追踪雷达的新雷达回响回应由跨关联(MTREC)在这研究被开发在不同空间规模分析雷达回响的运动。雷达回响的运动,特别地与对流暴风雪联系了,在导致对流暴风雪的形成的气象学的系统之中由于复杂相互作用在各种各样的空间规模展出不同特征。为空回响区域,平常的关联技术生产零或运动向量的很小的大小。减轻这些限制,MTREC由关联(TREC)使用追踪的雷达回响有一个大盒子的技术驾驶风驾驶的系统的运动,和MTREC与一个小盒子使用TREC技术决定估计小规模的内部运动向量。最后,MTREC向量被综合获得系统的运动和小规模的内部运动。MTREC技术的性能与用案例研究的TREC技术相比:Wenzhou雷达和一个嚎啕线系统在2005年9月11日在2011年6月23日观察的Khanun台风由北京雷达检测了。结果证明那更空间地变光滑,连续向量领域能被MTREC技术产生,它在追踪全部雷达反射率模式导致改进。新多尺度的追踪计划被使用在量的降水nowcasting的表演上学习它的影响。在一1-h铅时间的重降水的地点和紧张与使用雷达和雨计量器的量的降水估计更一致。