Study Land Surface Temperature Change Before And After The Yushu Ms7.1Earthquake Based On MODIS Data

The technique of satellite thermal infrared remote sensing,which has theadvantages of wide observing range,large amount of information,fast obtaininformation and long-term continues,widely applies in uban heat island effect,forestfire monitoring and dought monitoring.Scholars both at home and abroad discoveredthat change before moderate strong earthquake,and also in the process of rockfracture,thermal infrared image maps appear abnormal temperature,so that will be ameaningful exploration in earthquake.the thesis does some systematic researth onThermal infrared physics and fundamentals of land surface temperatureinversion,obtain MODIS data，data preprocessing,the surface temperature inversionmethod,algorithm derivation and program realization.Take the Yushu earthquake asexample,discuss temperatue changes before and after earthquake,The contents of thethesis are as follows：(1)Basic theory and obtain data.Analysis mastere basic concept of land surfacetemperature inversion and theory knowledge，MODIS probe character，data storageformats，radiation correction and geometric correction.(2)Land surface temperature inverse methods research.there are atmosphericradiative transfer theory method，single window algorithm and split window algorithmbased on MODIS data.Contrast and analysis methods,Comprehensive consideration ofthe methods advancement and the earthquake observation technology high precisionchoose split window algorithm as the thesis’s researth method.(3)Algorithm derivation and program realization.derive split windowalgorithm with details,clear the relationships between all parameters,realize thealgorithm on the ENVI+IDL platform.(4)Discuss Yushu earthquake temperature change.know basic geologicalbackground and meteorological condition of Qinhai provinceYushu earthquakefocus，contrast and analysis inverse temperature，analysis if there has temperaturechanges before and after earthquake.Through the above research work，the conclusions are as follows：(1)The thermal infrared band resolution of MODIS data is1000meter,theregenerally exists a variety of vegetation in a single pixel,affects emissivity of landsurface vegetation，thereby influences the accuracy.(2)Through validation,the accuracy of inverse temperature and Yushumeteorological station’s temperature reach normal.(3)Temperature in focal place is high than around，rathan than low,which needs further study what makes it so.In a word,there exists no obvious relationship between earthquake andtemperature change in the constraint of terrain,meteorological，the accuracy ofsatellite sensor.