Study On Thermal Infrared Remote Sensing Retrieval Method Of Surface Temperature In The Middle East Of The United States Based On FY-3D Data

As the primary industry,agriculture is the foundation of a country’s national economy and the fundamental guarantee for people’s life and survival.The Middle East region of the United States,located in the Central Great Plains of the United States,is one of the major agricultural regions of the United States.This area has strong soil fertility and rich organic matter,which is suitable for crop farming.The application of satellite remote sensing technology to land surface temperature retrieval has a certain guiding role in agricultural production,drought monitoring and other aspects in the region.At present,satellite remote sensing data used to retrieve land surface temperature mainly include multi band MODIS data and Landsat8 satellite data,while FY-3D MERSI-II remote sensing data is rare.In this paper,based on the two thermal infrared bands 24 and 25 of the FY-3D MERSI-II sensor,the universal single channel method is used to retrieve the surface temperature in the Middle East of the United States.The applicability of this method is discussed,and the cloud removal processing is carried out on the remote sensing images with clouds to obtain the all-weather surface temperature;By dividing the types of surface objects,curve fitting,precision verification and time-space analysis of the obtained surface temperature results were carried out,and finally the thermal infrared band 25 was determined to be more suitable for surface temperature inversion.The main research conclusions of this paper are as follows:1)The NDVI is used to estimate the surface temperature in the Middle East of the United States under the cloud coverage area.In the short term,when the vegetation types are relatively fixed,the vegetation index NDVI_A1and NDVI_B1show a linear positive correlation,while LST and NDVI_A1show a linear negative correlation;2)The NDVI is used to estimate the surface temperature in the Middle East of the United States under the cloud coverage area.Through accuracy verification,the results show that the surface temperature retrieved from the 25th thermal infrared channel of FY-3D MERSI-II is less deviated from the true value,and the estimation results are more accurate and closer to the true value.Both MAE and RMSE values are less than 1,which can meet the accuracy requirements of agricultural drought monitoring,ecological evaluation,crop yield estimation,etc;3)The surface feature types are divided into towns,vegetation and water bodies in turn.SPSS mathematical analysis software is used to analyze the retrieved surface temperature results to obtain curve fitting regression equations.R2,RMSE and validation data are used to test the accuracy and data validation of the obtained equations.Finally,thermal infrared band 25 is determined to be more suitable for surface temperature inversion.4)With the change of time,the temperature in the Middle East region of the United States gradually rose from January to the highest point in June or July,and then began to cool down.The temperature reached the lowest point in January or December,and the surface temperature showed a trend of rising first and then declining over time;The land surface temperature in the Middle East of the United States is classified into temperature grades.The land surface temperature decreases from the southwest to the northeast of the Lake Michigan region,showing the status quo of high in the south and low in the north,high in the southwest and low in the northeast.