Primary Study Of Typhoon Monitoring Using Seismic Network Data

In recent years, disasters happen frequently in our country ,which are include byore ,wind, hail, flood, drought and so on, already has coursed the significant propertiesand life loses, the disasters coursed by typhoon are most serious, disaster preventionand reduction becomes test on a society synthesizes the quality omni-directional andthe examination, in view of the typhoon disaster, the research work included in thisthesis are the following:Firstly, this thesis makes research on the wide-broadband velocity records obtainedby Seismic monitoring Network of Fujian province, during the total process of typhoonformation and development , the typhoon is a huge energy body , facing the typhoon sohuge energy, most direct-viewing response is the waveform change, this papercompares the waveform record during typhoon to the daily noise or the astronomy tide,discovers that two vibrations amplitude and period remarkably are different, presents akind of energy specific parameters expressed by root-mean-square velocity abstractedfrom moving time window technique ,computes the continuously timeroot-mean-square velocity values, we discover the root-mean-square velocity is groupof very orderly spots, corresponds these and the typhoon characteristic, could discoversome qualitative results, moreover the records which are influenced by the daily noise,the astronomy tide have been certainly understood.Secondly, this paper uses the broadband records from the Fujian Seismic network,take one hour as a time window, studies entire process spectrum characteristic duringthe total process of typhoon formation and development, compares the Fourierspectrum during typhoon to noise ,finds the typhoon signal ,takes one kind of portraytyphoon characteristic with the Fourier spectrum predominate period. The researchindicates that, initial forms at the stage in the typhoon, the predominate periods byordinary noise 1s, jump to 7s ~ 8s, and the periods will slowly reduce along with thetyphoon motion to land ,especially will remarkably reduce after the Taiwan Straits, thepredominate period will restore gradually for the noise level along with the typhoonlanded.Finally, after using upon method pick-up typhoon signal, this paper uses leastsquares method to fit these data. Fitting the root-mean-square velocity, this thesismainly considers the intensity and distance influence, utilizes two steps method, likethis, we consider to the relevance between the intensity and distance, obtain thesatisfactory results. The statistical regression of predominate periods mainly considersthe typhoon intensity and the Doppler effect, and have introduced the typhooninfluence beginning wind-speed parameter, make the entire model of physicssignificance to be brighter.This thesis results indicate ,the broadband velocity records because the sampling ratehigh, the band width, the bigger dynamic range, may monitor continuously the typhoonmotion process, because the meteorological satellites monitor a time for each hour, thismonitor is an important supplement to the satellites.