LST Retrieval algorithms F oreword In many environments models, such as atmospheric and surface energy and water v apor exchange, digital weather forecasting, global ocean currents, climate change, etc., LST is an indispensable parameter. we can obtain a regional or global surface temperature distribution only through remote sensing technology. F oreword (continue) R ecent years, many methods have been used to estimate the surface temperature through the detected thermal infrared band which usually effected by atmosphere Basis Surface and atmosphere are both thermal infrared radiation source Radiation can pass through the atmosphere many times being absorbed,scattered and emitted. Planck formula ?: atmospheric transmissivity ?: Surface Emissivity NDVI : Normalized Difference Vegetation Index Surface Emissivity It reflects the nature of the radiation properties ( ) [ (1 ) ]/ s B T L L L ? ? ?? ??? ??????? platform : ENVI ( The Environment for Visualizing Images ) ? Data :石家庄 2013/07/25 Path124&Row34 ( 114:26E 38:03N ) include 7 bands from 地理空间数据云(中国科学院计算机网络信息中心提供) NVDI ?ε water= ( when NDVI le 0 ) ?ε surface = + - ?( when NDVI ge ) ?ε building = + - ( when NDVI gt 0 and bt lt ) Emissivity ENVI Basic Tools->Band Math , type in : ( b1 le 0 )*+ ( b1 gt 0 and b1 lt )* ( + *b1 - *b1 ^2)+(b1 ge ) * ( + *b1 - *b1 ^2) b1 : NDVI Surface Emissivity
