简介:省气象信息网络中心自1995年8月份起处理、上网GMS—5卫星云图,给各网络用户提供三个通道、二种投影共五类云图图象产品,即红外兰勃脱图、红外麦考托图、可见光麦考托图、水汽兰勃脱图和未投影的可见光图.本文介绍了卫星图象产品的特点、接收情况及各种云图的观测原理,供大家参考.1新卫星与GMS—4卫星的不同点及接收简况GMS—5卫星是1995年3月份日本发射的静止卫星,它与GMS—4相比作了一些改进,将GMS—4的红外探测通道波段10.5~12.5μm分割为两个通道,红外1:10.5~11.5μm,红外2:11.5~12.5μm并增加了红外3为水汽通道,波段为6.5~7.0μm,可见光波段从0.55~0.75μm改为0.55~0.90μm.
简介:模拟用一个修改中央缩尺模型被执行,极的MM5,它在极的区域以内为使用被改编。学习的目的是在在北极硫上模仿大气的行为说明极的MM5的技巧。自动气象站数据,全球大气的分析,以及近表面、上面空气的观察被用来验证模拟。在191997年4月29日模拟揭示了的时期以内的极的MM5和原来的MM5的平行模拟那极的MM5为在北美人上定位的区域比原来的MM5复制了更好近表面的变量预报北极区域。由极的MM5的很好预言的近表面的温度和混合比证实在这个模型被使用的修改物理parameterization计划为北极河区域是适当的。然后,在北美人和欧亚的领域上的极的MM5模拟的扩大评估然后在到2003年5月15日的2002年12月15日期间被执行。从在为在850hPa和500个hPa变量的近表面、垂直的侧面的16个车站的观察和极的MM5模拟的时间序列阴谋和统计分析被分析。模型被发现与精确性的高度在大小和可变性两个都复制观察大气的状态,特别为温度和近表面的风,尽管有细微冷偏爱,在表面附近存在。
简介:基于国际耦合模式比较计划第五阶段(CMIP5)历史试验(historical)的输出结果,评估了26个耦合模式对北极涛动(AO)的模拟能力。对各模式逐月AO指数序列的功率谱分析表明,有23个模式能够模拟出AO模态无碱著变化周期的特征。这些模式也能够较好地再现冬季AO在海平面气压场上的主要分布特征,但均高估了AO模态的强度。对于伴随着冬季AO位相变化而出现的中高纬度偶极型的纬向平均纬向风异常,CMIP5中只有一些模式柯较好的模拟表现,大多数模式对其中心位置和强度的模拟存在明显不足。对比之下,MPI-ESM-P对AO时空特征的模拟更接近观测结果。
简介:Thetrack,landfall,dynamicandthermodynamicandcloud-rainphysicalmesoscalestructuresandtheirevolutionoftyphoonHERB1996in36hfrom0000UTC31Julyto1200UTC1August1996weresimulatedbyusingthenon-hydrostaticmesoscalemodelMM5.ThisperiodcoveredtheprocessoftyphoonHERBlandfallatTaiwanandFujianProvinces.ResultsshowthatthemodelsuccessfullysimulatedthelandfallprocessoftyphoonHERB,revealedthemostimportantcharacteristicsofthemesoscaledynamicandthermodynamicandcloud-rainphysicalstructureduringitslandfall.Thesimulatedtyphoontrackwasclosetotheobservation.Thecenterofcycloniccirculationsimulatedat0000UTCon1August1996(24hintegration)waslocatedinshorenearFuqing,FujianProvinceatwhichthetyphoonwasreportedtolandfalltwohourslater.Itshowsthatstrongupwardmotionformedbylowlevelconvergenceexistedintheeye-wallandsubsidenceattheeye.Thewindfieldshowsclearasymmetricalstructurenearthetyphooncenter.Thecloudandrainbandwasscrew-typeddistributedaroundtyphooncenter,andconsistedofmeso-βscaleraincores.DuringtheperiodoftyphoonHERBstayingnearandpassingoverTaiwan,thelowercloudwasdevelopedintheeyeregionsothatthepreviouscleartyphooneyeonthesatellitepicturesbecamefuzzy.Observationshowsthatthetyphooncenterwas"warm",butthemodelsimulationswithhigherspaceresolutionshowthatinthemid-tropospheretheregionofeye-wallwithstrongerupwardmotionandmorecloud-andrain-waterwaswarmerthantheeye.DuringtheperiodoftyphoonpassingoverTaiwananditsfollowinglandfallatFujian,thetrackofmodeltyphoondeviatedabout30kmnorthward(i.e.,rightward)becauseoftheorographiceffectsofTaiwanIsland,butthestrengthofthetyphoonwasnotaffectedremarkably.TheamountofrainfallonTaiwaninthe36hsimulationswasenhancedmorethansixtimesbytheorographicliftingofTaiwanMountain.
简介:Thisstudyexaminespre-industrialcontrolsimulationsfromCMIP5climatemodelsinanefforttobetterunderstandthecomplexrelationshipsbetweenArcticseaiceandthestratosphere,andbetweenArcticseaiceandcoldwintertemperaturesoverEurasia.WepresentnormalizedregressionsofArcticsea-iceareaagainstseveralatmosphericvariablesatextendedleadandlagtimes.Statisticallysignificantregressionsarefoundatleadsandlags,suggestingbothatmosphericprecursorsof,andresponsesto,lowseaice;butgenerally,theregressionsarestrongerwhentheatmosphereleadsseaice,includingaweakerpolarstratosphericvortexindicatedbypositivepolarcapheightanomalies.Significantpositivemidlatitudeeddyheatfluxanomaliesarealsofoundtoprecedelowseaice.Wearguethatlowseaiceandraisedpolarcapheightarebotharesponsetothisenhancedmidlatitudeeddyheatflux.Theso-called"warmArctic,coldcontinents"anomalypatternispresentonetotwomonthsbeforelowseaice,butisabsentinthemonthsfollowinglowseaice,suggestingthattheEurasiancoolingandlowseaicearedrivenbysimilarprocesses.Lastly,ourresultssuggestadependenceonthegeographicregionoflowseaice,withlowBarents-KaraSeaicecorrelatedwithaweakenedpolarstratosphericvortex,whilstlowSeaofOkhotskiceiscorrelatedwithastrengthenedpolarvortex.Overall,theresultssupportanotionthattheseaice,polarstratosphericvortexandEurasiansurfacetemperaturescollectivelyrespondtolarge-scalechangesintroposphericcirculation.