Detecting Aerosols over Land from Satellites by Measuring Far IR Radiation from the Earth-Atmospheric System

In this study, a special method is proposed for detecting aerosols over land by analyzing satellite-measured far IR radiation at three channels, 8.7, 11.5, and 12.5 um. Sensitivity tests revealed that the behavioral features of radiative brightness temperatures (BTs) at these three channels with increasing optical depth are different among different types of aerosols. Analyzing how BTs and their differences, xBT (BT11.5-BT12.5) and yBT (BT8.7-BT11.5), behave with varying optical depth can help to qualitatively distinguish among aerosols and semi-quantitatively estimate their optical thicknesses. In addition, the authors found that the vertical density profile of aerosols has little impact on this method.