简介：BithyniaisaregioninthenorthwestofAnatoliaborderedbytheBlackSea(PontusEuxeinos)tothenorth,theDardanelStrait(Hellespontos)andKocacay(Rhyndakos)tothewest,andtheSakaryaRiver(Sangarios)tothesouth.ApointoftheAsiancontinentextendingtowardsEurope,Bithyniaissurroundedbyseasonitsthreesidesandhasalongshore.Nicomedeia,oncethecapitalofBithynia,isanimportantcityduetoitslocation.Sincethegulfis

简介：简单介绍了法国DEMETER（detectionofelectro—magneticemissionstransmittedfromearthquakeregions）地震电磁卫星的科学任务，以及所搭载载荷和观测模式。利用卫星观测资料研究了2006年6月20日16点52分（UT时间）发生在我国甘肃境内的5．0级地震。结果发现，在此次震前第5天电离层就开始出现异常现象，在震前大约1～2天时，这种异常达到最大。最后简述了发展卫星观测所面临的挑战和机遇。

简介：ThispaperisrelatedtostudyoftheiondensityrecordedbythelowaltitudesatelliteDEMETER.Itwillpresentionosphericperturbationsobservedduringlargeseismicevents.Astheionosphereishighlyvariable,thepaperwillshowastatisticalanalysisperformedontheplasmaparametersduringnighttime.Analgorithmhasbeenimplementedtodetectcrestsandtroughsinthedatabeforeworld-wideearthquakes.Theearthquakeshavebeenclassifieddependingontheirmagnitude,depth,andlocation(land,belowthesea,closetoacoast).Duetotheorbit,DEMETERreturnsabovethesameareaeveryday(onceduringdaytime,onceduringnighttime)butnotatthesamedistanceofagivenepicenter.Then,foreachearthquake,datahavebeencheckeduntil15daysbeforetheshockwhenthedistancebetweenthetraceoftheorbitandtheepicenterislessthan1500km.Theresultsofthestatisticalanalysisarepresentedasfunctionsofvariousparameters.Acomparisonisdonewithtwootherdatabaseswhere,ononehand,thelocationoftheepicentershasbeenrandomlymodified,andontheotherhand,thelongitudeoftheepicentershasbeenshifted.Resultsshowthatthenumberandtheintensityoftheionosphericperturbationsarelargerpriortoearthquakesthanpriortorandomevents,andthattheperturbationsincreasewiththemagnitude.

简介：ThedataofionosphericperturbationsobservedonDEMETERbeforethe2007Pu'erearthquakeareanalyzed.Thethree-componentplasma(ions,electronsandheavyions)isstudiedinthefluidconcept.Thelineardispersionrelationforion-acousticwaveisfoundinthepresenceofheavyions.Thenonlineardynamicsisstudiedforarbitraryamplitudeofthewave.TheSagdeevpotentialiscalculated,whichshowsthatsolitarystructureexistsforMachnumberwithinarangedefinedbythepresenceofheavyions.Thedevelopedion-acousticsolitonsmaybeusedasprecursorforearthquakeprediction.

简介：文章评估耦合气候模式预测台风季节（6～10月）西北太平洋纬向风垂直切变幅度（Mws）的年际变化能力，分析显示欧洲多模式集合气候预测系统计划（DEMETER）中耦合模式数据基本具有回报MWS基本空间分布特征的能力，而回报MWS空间能力的不足区域与模式回报MWS与西北太平洋年台风数（WNPTF）的虚假显著相关区域相一致。过程中还显示西北太平洋低纬海区MWS与WNPTF正（负）相关，而强E1Nino年时该海区MWS对应正（负）异常，强LaNina年时则相反；这意味着在台风季节，强EINino年的WNPTF容易比强LaNina年的WNPTF偏多。在考察MWS的时间变异特征时，将MWS区域平均时间序列（MWST）和MWS的EOF第一特征向量对应的时间系数（MWSPCI）定义为纬向风垂直切变指数，讨论指数与WNPTF、强ENSO间的关系。分析显示，MWST（MWSPCI）分别与Nino3．4指数、WNPTF显著相关，模式集合较好地再现了这种特征；但对强ENSO信号的响应，两个指数在ERA．40数据中是相反的，而在模式集合中却是一致的。