A study of soil surface temperature with thermal infrared measurement

The measurements of air temperature and air humidity were employed to analyze the diurnal variation of atmospheric emissivity over unirrigated bare soil, from March 20th to April 20th, 2002, at XiaoTangShan area, Beijing. Further, sky radiative temperature and soil radiative temperature with thermal infrared multi-angles were used to study the differences between surface radiative temperature over bare soil without being calibrated and calibrated with standard blackbody and the differences between surface "true" temperature, which were calculated with the downwelling longwave ambient radiation and soil emissivity, and surface radiative temperature, which were calibrated by standard blackbody. The results may be scientific reference to invert land surface temperature with remote sensing and to study land surface energy balance.