简介:Consideringtheimportanceofblackcarbon(BC),thisstudybeganbycomparingthe20thcenturysimulationofSouthAsiansummerclimateinIPCCCMIP3,basedonthescenarioofmodelswithandwithoutBC.Generally,themulti-modelmeanofthemodelsthatincludeBCreproducedtheobservedclimaterelativelybetterthanthosethatdidnot.Then,the21stcenturySouthAsiansummerprecipitationwasprojectedbasedontheIPCCCMIP3projectionsimulations.Theprojectedprecipitationinthepresentapproachexhibitedaconsiderabledifferencefromthemultimodelensemblemean(MME)ofIPCCAR4projectionsimulations,andalsofromtheMMEofthemodelsthatignoretheeffectofBC.Inparticular,thepresentprojectionexhibitedadryanomalyoverthecentralIndianPeninsula,sandwichedbetweenwetconditionsonthesouthernandnorthernsidesofPakistanandIndia,ratherthanhomogeneouswetconditionsasseenintheMMEofIPCCAR4.Thus,thespatialpatternofSouthAsiansummerrainfallinthefuturemaybemorecomplicatedthanpreviouslythought.
简介:NonhydrostaticmesoscaleWRFandits3D-Varsystemareusedtostudyadensefogeventoccurringin13-14January2006.ThreedifferentobservationdatasetsincludingGTS(GlobalTelecommunicationSystem),AMDAR(AircraftMeteorologicalDataRelay)data,and9210dataareassimilatedintotheinitialanalysisfieldsinexperiments.Experimentswiththreedifferentassimilationtimeintervals(1,3,and6h)arealsocarriedout.Threeexperimentswithdifferentdatasetshaveallmodifiedthetemperatureandhumidityfieldofinitialfields,andthereforeshowanobviouspositiveeffectonfogsimulation.Furtherstudyindicatesthatthehumidityandstabilityofboundarylayerareimprovedobviouslyinassimilationexperiments,althoughdifferentdatasetsmakedifferentcontributiontotheanalysisfields.Themulti-timeassimilationcycleexperimentsshowthattheanalysisincrementinexperimentwith1-hintervalismorerealisticthanthatwith3-and6-hintervals.
简介:The3-hour-intervalpredictionofground-leveltemperaturefrom+00houtto+45hinSouthKorea(38stations)isperformedusingtheDLM(dynamiclinearmodel)inordertoeliminatethesystematicerrorofnumericalmodelforecasts.NumericalmodelforecastsandobservationsareusedasinputvaluesoftheDLM.AccordingtothecomparisonoftheDLMforecaststotheKFM(Kalmanfiltermodel)forecastswithRMSEandbias,theDLMisusefultoimprovetheaccuracyofprediction.
简介:利用常规观测资料、自动气象站降水资料和NCEP1°×1°资料,对2009年7月辽宁省3次局地短时暴雨的500hPa位势高度场、垂直速度场、sθe场和水汽通量场进行对比分析。结果表明:3次局地暴雨过程中,辽宁西部和北部的暴雨落区与上升速度中心对应,而辽宁东南部暴雨落区位于上升区边缘;露点锋、中α尺度低压和暖式切变线对三次短时暴雨过程起到触发作用;当T639降水产品预报降水时段内有大范围的小雨天气,说明将有弱的天气尺度强迫出现,此时应重点分析水汽辐合、高能舌和上升速度大值中心叠加的区域;如果该区域存在中尺度系统触发机制,则该区域可能是局地暴雨的落区。
简介:2006年5月29日至6月9日,由国际理论物理研究中心(TheAbdusSalamInternationalCenterforTheoreticalPhysics,ICTP)主办的第3届区域气候模式理论和应用研讨会(ThirdICTPWorkshopontheTheoryandUseofRegionalClimateModels),在意大利的滨海城市的里雅斯特(Trieste,ICTP的所在地)举行。与会人员包括来自不同国家的140余名专家、学者和学员。高学杰研究员代表国家气候中心,是会议的5名组织者之一,与国家气候中心徐影博士,研究生张冬峰、石英、曹丽娟,访问学者徐集云(浙江省气象局)参加了会议。中国农业科学院、中国科学院大气物理研究所等单位的专家和研究生也应邀参加了会议。