简介：ＰＥＲＳＰＥＣＴＩＶＥＳＯＦＴＲＯＰＩＣＡＬＣＹＣＬＯＮＥＵＮＵＳＵＡＬＭＯＴＩＯＮＳ──ＴＨＥＤＩＦＦＩＣＵＬＴＩＥＳＩＮＣＵＲＲＥＮＴＴＲＯＰＩＣＡＬＣＹＣＬＯＮＥＦＯＲＥＣＡＳＴＩＮＧＣｈｅｎＬｉａｎｓｈｏｕ（陈联寿）ＣｈｉｎｅｓｅＡｃａｄｅｍ...

简介：Altera公司拓展其CycloneFPGA系列并延续其收发器技术优势，发布了CycloneIVFPGA新系列。

简介：Altera公司发布具有安全特性的低功耗系列FPGA。新的AlteraCycloneⅢLSFPGA在单位面积电路板上具有密度最大的逻辑、存储器和DSP资源。这些器件功耗极低，200K逻辑单元（LE）的静态功耗低于0．25W。现在已经开始发售的CycloneⅢLSFPGA面向所有市场领域中对功耗和电路板面积非常敏感的应用。

简介：Usingmeteorologicaldataoffieldobservationin1990～2000,especiallypolarorbithighresolutionNOAAsatellitecloudmapsreceivedfromtheAntarcticexpeditionvesselsince1997,theformationanddevelopmentofthePrydzBaycyclonearestudiedinthispaper.Somenewviewpointsaresuggestedsuchas:whensurround-polarcycloneentersthePrydzBay,itcanalsointensifyanddevelopinsummer;cyclonecanalsodevelopintheeasterliesinthisbay.TheseviewpointsreviseolduncompleteviewpointthatthePrydzBayisaburialgroundofcyclone,andalsofurtherconsummateformation-developmenttheoryofsurround-cycloneintheAntarcticwesterliesandcycloneintheAntarcticeasterlies.Inthispaper,themechanismofice-air-seainteractioninthePrydzBayisstudied,andthephysicalprocessofcycloneformation-developmentisexplained.Byuseofwhollydynamictransportationmethod,anenergyexchangecaseofacyclone,whichexplosivelydevelopedafterenteringthePrydzBay,iscalculated.Intheopenwaterarea,momentumfluxis-2.205N/m2,sensibleheatfluxis486.69W/m2,andlatentheatfluxis261.84W/m2.ItislargerthanvaluesofwesterliesburstoverthePacific.Theheattransferredfromoceantoatmosphereinformofsensibleandlatentheatpromotescyclonedevelopmentrapidly.Inthiscasewindforcewasasstrongas12grade,with10minutesaveragewindspeedof38m/s,andinstantaneouswindspeedof100m/swhichbrokethewindspeedrecordof96m/sintheAntarctic(WendlerandKodama).

简介：UsingthemethodofSingularSpectrumAnalysis(SSA),theevolutionregularityoftropicalcycloneslandinginGuangdongareanalyzed.ThemainperiodsofyearlytopicalcycloneslandinginGuangdongarefoundat8andquasi-3years,andinthewestofPearlRiverMouthare12andquasi-2yearstothewestofPearlRiverMouth.ThenorthwestPacificthattopicalcyclonesaregeneratedisdividedinto8areas,andtheSea-SurfaceTemperature(SST)ineachareaisanalyzedusingSSA.ThemainperiodsofNINO-westare8and3years,andthoseofthewarmpoolare12and2years,respectively.ThismaybethephysicalreasonforthegenerationtropicalcycloneslandinginGuangdong.BycombiningtheMaximumEntropyMethod(MEM)withSSA(SSA-MEM),theyearlyvariationtrendoftropicalcycloneslandinginGuangdongandthePearlRiverMouthareforecast,andtheresultsaregood.Themethodcanbeusedinoperationalshort-rangeclimateforecast.

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简介：基于改进客观气旋察觉和追踪的算法，在在北东亚的热带以外的气旋的十的变化被使用ECMWF40年分析(ERA-40)学习海平面的压力数据在期间19582001。结果表明那项热带以外的气旋活动显示了清楚季节，内部在北东亚的年度、十的可变性。春天是气旋最经常发生的季节。热带以外的气旋的空间分发证明气旋主要在40°以内发生50°N在北东亚的纬度的乐队，和出现的最经常的区域在蒙古。而且，这研究也揭示热带以外的气旋的频率显著地在北东亚的更低的纬度区域减少了在期间的事实19582001，但是十的可变性在更高的纬度乐队统治了，与经常的气旋开始。热带以外的气旋的紧张在一个年度、季节的基础上减少了。在北东亚的气旋的年度数字的变化与baroclinic的吝啬的紧张被联系正面的地区，它被在更高的纬度温暖的气候影响。而且，随北方的增加和在北东亚的南部的部分的减少，额外的热门气旋变化的偶极子结构与有关向北方baroclinic的运动110°E的任何一个方面上的正面的地区。

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简介：Overthepast25years,anannualaverageof6to7tropicalcyclones(TCs)madelandfallonChinamainlandandHainanIslandwithanaverageintensityof29.9m/satlandfallandmaintainedatleasttropicalstormintensityfor15.6hoursoverland,leadingto505deathsand37billionyuanindirecteconomicloss,whichaccountedfor0.4%oftheannualGDPofChina.Althoughtherewaslittlechangeintheoveralllandfallfrequency,intensityatlandfallandoverlandduration,theannualtotaldirecteconomiclossincreasedsignificantlyduetotherapideconomicdevelopmentoverthepast25years.Underglobalwarming,theintensityofTCsthatmadelandfallonHainandecreasedbuttheoverlanddurationandfrequencyofTCsthatmadelandfallonFujianandZhejiangincreased.Atthenationalandprovinciallevels,theratioofthedirecteconomiclosstoGDPandcasualtiescausedbylandfalltropicalcyclonesdecreased,suggestingtheeffectivenessofdisasterpreventionandreductioninChina.

简介：ＩＮＮＥＲＡＮＤＯＵＴＥＲＳＴＲＵＣＴＵＲＥＳＯＦＴＲＯＰＩＣＡＬＣＹＣＬＯＮＥⅡ．ＢＡＲＯＣＬＩＮＩＣＭＯＤＥＬ￥ＬｉｕＳｈｉｋｕｏａｎｄＬｉｕＳｈｉｄａ刘式适，刘式达（ＤｅｐａｒｔｍｅｎｔｏｆＧｅｏｐｈｙｓｉｃｓ，ＰｅｋｉｎｇＵｎｉｖｅｒｓｉｔｙ...

简介：Tohaveaclearerpictureofmechanismsresponsibleforthedeviationoftropicalcyclone(tobesimplifiedasTChereafter)tracks,thecurrentworkassumestheTCasacircularvortexwitharadiusofR.AgeneralmotionequationofTCisthendeterminedbyaveragingitshorizontalmotionequationoverthesentireregionofTC.Inthemeantime,withthemovingtrackofTCassumedasacharacteristicarc,thecurvatureequationisderivedforthetrackofmovementandpatternsofitsdeviationduetoTCstructureandvariationarediscussed.Theresultshowsthatthescale,size,maximumwindspeedandradiusarefactorscausingthedeviationofTCtracks.Inaddition,asymmetricstructureofTCisalsoimportantforthedeviationoftracks.Theresults,achievedwithhypothesis,agreewithfactsinsomecasesbutdisagreewiththeminothers,whicharetobeverifiedwithmoreobservationsornumericalsimulations.

简介：ＴＨＥＤＹＮＡＭＩＣＳＯＦＭＡＩＮＴＡＩＮＩＮＧＴＨＥＴＲＯＰＩＣＡＬＣＹＣＬＯＮＥ９０１２ＡＦＴＥＲＩＴＳＬＡＮＤＩＮＧ￥ＬｉａｎｇＬｉ，ＷｕＺｈｉｗｅｉ（ＭｅｔｅｏｒｏｌｏｇｉｃａｌＩｎｓｔｉｔｕｔｅｏｆＦｕｊｉａｎＰｒｏｖｉｎｃｅ，Ｆｕｚｈｏｕ...

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简介：

简介：AwesternNorthPacifictropicalcyclone(TC)intensitypredictionscheme(WIPS)isdevelopedbasedonTCsamplesfrom1996to2002usingthestepwiseregressiontechnique,withthewesternNorthPacificdividedintothreesub-regions:theregionnearthecoastofEastChina(ECR),theSouthChinaSearegion(SCR),andthefaroceanicregion(FOR).OnlytheTCswithmaximumsustainedsurfacewindspeedgreaterthan17.2ms1areusedinthescheme.Potentialpredictorsincludetheclimatologyandpersistencefactors,synopticenvironmentalconditions,potentialintensityofaTCandproximityofaTCtoland.VariancesexplainedbytheselectedpredictorssuggestthatthepotentialintensityofaTCandtheproximityofaTCtolandaresignificantinalmostalltheforecastequations.OtherimportantpredictorsincludeverticalwindshearinECR,500-hPageopotentialheightanomalyattheTCcenter,zonalcomponentofTCtranslationspeedinSCR,intensitychangeofTC12or24hpriortoinitialtime,andthelongitudeofTCcenterinFOR.IndependenttestsarecarriedoutforTCsin4yr(2004-2007),withmeanabsoluteerrorsofthemaximumsurfacewindbeing3.0,5.0,6.5,7.3,7.6,and7.9ms1for12-to72-hpredictionsat12-hintervals,respectively.Positiveskillsareobtainedatallleadingtimelevelsascomparedtotheclimatologyandpersistencepredictionscheme,andthelargeskillscores(nearorover20%)after36himplythatWIPSperformsespeciallybetteratlongerleadingtimes.Furthermore,itisfoundthattheamendmentinTCtrackpredictionandreal-timemodelanalysiscansignificantlyimprovetheperformanceofWIPSintheSCRandECR.FutureimprovementswillfocusonapplyingtheschemeforweakeningTCsandthosenearthecoastalregions.

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简介：Theeffectsofverticalwindshearontropicalcyclone(TC)intensitychangeareexaminedbasedontheTCdatafromtheChinaMeteorologicalAdministrationandtheNCEPreanalysisdailydatafrom2001to2006.First,theinfluenceofwindshearbetweendifferentverticallevelsandaveragesindifferenthorizontalareasarecompared.Theresultsindicatethattheeffectofwindshearbetween200and850hPaaveragedwithina200-800kmannulusonTCintensitychangeislargerthananyothercalculatedverticalwindshear.High-latitudeandintenseTCstendtobelesssensitivetotheeffectsofVWSthanlow-latitudeandweakTCs.TCsexperiencetimelagsbetweentheimpositionoftheshearandtheweakeninginTCintensity.Averticalshearof8-9m/s(9-10m/s)wouldweakenTCintensitywithin60h(48h).Averticalsheargreaterthan10m/swouldweakenTCintensitywithin6h.Finally,astatisticalTCintensitypredictionschemeisdevelopedbyusingpartialleastsquaresregression,whichproducesskillfulintensityforecastswhenpotentialpredictorsincludefactorsrelatedtotheverticalwindshear.Analysisofthestandardizedregressioncoefficientsfurtherconfirmstheobtainedstatisticalresults.

简介：在理想化的热带气旋(TC)的对流结构与变化联系在期间的物理过程乍见陆地用大气的研究Mesoscale模型，的第五产生的宾夕法尼亚州的大学公民中心在一架贝它飞机上被学习版本3(MM5)。模拟结果建议潮湿供应和增加的磨擦的抑制行动了在不同时期期间从左和TC的前面象限提高传送对流到TC的前面和权利乍见陆地。当表面潮湿流动被关掉时，在象限的另外的部分的传送对流清楚地被压制，全部的降雨被减少。当表面磨擦被增加时，降水在乍见陆地做的TC以后显示出显著增加。在低、中间的层次的更湿的空气，和在在海岸线的向陆的方面附近的高水平的更干燥的空气导致了对流可得到的势能(披肩)的高价值。因而，当表面潮湿流动被割掉时，传送对流这个区域下游地立即被提高。当表面磨擦被增加时，物理过程是类似的在以前乍见陆地。在以后乍见陆地，在陆地的向陆的方面的增加的集中在TC前面导致了提高的传送对流。与以前的调查结果一致，我们的结果建议那在期间乍见陆地，从到不对称现象的热力学的对称之一的TC结构变化由于在陆地和海之间的微分潮湿流动出现。热力学的结构的不对称现象，能被披肩的分发解释，引起不对称的降雨结构。关键词热带气旋-乍见陆地-对流不对称现象

简介：响应影响环境条件的活动被付了越来越多的注意到的热带气旋(TC)的变化在最近的年里。单身者和multivariate的潜在的贡献到从1970～2009的年度TC频率和紧张的环境变量在这研究被调查。而不是使用关联系数，那假定一套样品令人满意正常分发，量的大小基于信息理论被提出。结果证明动态环境变量在西方的诺思太平洋，诺思大西洋，和东方太平洋上在TC活动的变化起一个重要作用。这些动态因素包括风在850和200hPa和850-hPa亲戚涡度之间砍。然而，在TC活动的热因素的效果在不同的盆上是不同的。热环境变量仅仅在北方大西洋上在东方太平洋上以及到TC频率有重要贡献到TC频率和紧张。影响TC活动的主要因素是，这被发现确实并非在不同的盆上的一样因为处于越过不同区域的大气的条件和他们的变化的差别。动态变量的效果应该在象热条件总是满足的西方的诺思太平洋那样的区域更被考虑。