Study on land surface temperature retrieval from HJ-1B infrared data

Abstract

Land surface temperature (LST) is an important measurement for estimating equilibrium of income and expense of land surface energy. It is also a key input parameter in many geographic models. Therefore, research on land surface temperature retrieval has close relation with thermal infrared-related study, such as hydrology, ecology, climatology, environment and other fields. Made in China, the Small Satellite Constellation for Environment and Disaster Monitoring and Forecasting is an advanced satellite constellation (composed of satellite HJ-1A, 1B and 1C) designed for environment and disaster monitoring and mitigation. Whether the sensor data can reach the designed specifications and meet the demands of application? It is necessary to carry out relative research before the launch of a new satellite. There is an infrared sensor in HJ-1B. Our work has been done before the launch of HJ-1B. This paper focuses on the land surface temperature retrieval study based on HJ-1B thermal infrared data, which is significant for its potential assessment and effective application in environment monitoring and disaster preventing and management. According to the characteristics of HJ-1B thermal infrared sensor, a method of using middle infrared (MIR) band and thermal infrared (TIR) band of HJ-1B is put forward in this paper. The spectral response function of bands, standard atmospheric profiles data and radiation transfer simulating software-MODTRAN are used to get simulated HJ-1B infrared data. And finally, the algorithm accuracy is estimated by comparing the retrieval value and true value of temperature. And the sensitive analyzing of retrieval algorithm is made through some main parameters. It can be know from our research that the proposed land surface temperature retrieving algorithm for HJ-1B infrared data has a considerable precision, the RMSE value range is 0.01K~2.08K. The RMSE increases with the increase of view zenith angle. The variation range of temperature retrieval RMSE due to view zenith angle is 0.1K~0.2K. The emissivity and water vapor content influence the land surface temperature retrieving result obviously, and the influence of instrument noise on retrieving result is little and can be ignored.