简介:WeretrospectivelyanalyzedthetemporalandspatialvariationsoffourdifferentphysicalparameterscharacterizingthestateoftheatmosphereandionosphereseveraldaysbeforetheM9Tohoku,JapanearthquakeofMarch11,2011.Thedataincludeoutgoinglongwaveradiation(OLR),GPS/TEC,lowerEarthorbitionospherictomographyandcriticalfrequencyfoF2.OurfirstresultsshowthatonMarch7tharapidincreaseofemittedinfraredradiationwasobservedfromthesatellitedataandananomalydevelopedneartheepicenter.TheGPS/TECdataindicateanincreaseandvariationinelectrondensityreachingamaximumvalueonMarch8.StartingfromthisdayinthelowerionospherealsotherewasconfirmedanabnormalTECvariationovertheepicenter.FromMarch3to11alargeincreaseinelectronconcentrationwasrecordedatallfourJapaneseground-basedionosondes,whichreturnedtonormalafterthemainearthquake.ThejointpreliminaryanalysisofatmosphericandionosphericparametersduringtheM9Tohoku,Japanearthquakehasrevealedthepresenceofrelatedvariationsoftheseparametersimplyingtheirconnectionwiththeearthquakeprocess.Thisstudymayleadtoabetterunderstandingoftheresponseoftheatmosphere/ionospheretothegreatTohokuearthquake.
简介:当前在进行水文测验工作中,采用走航式ADCP进行流量的测验被广泛应用。走航式ADCP的测验应用相对传统的流速仪的测验方法,在测验的准确性和工作原理等方面有着较大的优势。本文就结合走航式ADCP流量测验和传统的流速仪的测验方法进行对比,提出采用走航式ADCP应用在流量测验中的优势所在。