ON THE RELATIONSHIP BETWEEN THE CHAHINE-TWOMEY AND MAXIMUM-ENTROPY METHODS

The problem of estimating atmospheric temperature and composition prof iles from satellite-sensor or ground-sensor radiance measurements is g enerally ill-conditioned, so that constraints must be imposed to obtai n a unique solution. A number of estimation methods have been develope d, some of which incorporate explicit constraints whilst in others the constraints are implicit. In this correspondence we relate the Chahin e-Twomey method to a special case of the Maximum Entropy method. This relationship provides insight into the operation of the Chahine-Twomey method, and explains how this method incorporates a priori informatio n.