Inversion of ground-based radiometric data by Kalman filtering

Patrizia Basili, Piero Ciotti, and Domenico Solimini

Abstract

Retrieval of atmospheric vertical temperature profiles from ground-based radiometric observations requires shrewdness and judicious choice of parameters to surmount the noxious effects of the ill-posed nature of the inversion. Kalman linear estimation, already successfully used in satellite microwave sounding of atmospheric temperature, can be also applied to infer the thermal state of the lower troposphere from ground-based infrared measurements. After a short survey of the relevant formalism, the implementation of the Kalman filter is discussed with regard to the transition operator and to the error covariances. In particular, the measurement errors are considered in some detail , and their dependence on the atmospheric dynamics is pointed out. The attainable spatial resolution is compared with that of another commonly used inversion technique, and, finally, a set of temperature profiles estimated by the Kalman algorithm from a sequence of successive radiometric measurements is reported.

Index Terms - Atmosphere. Infrared. Radiometry. Profile retrieval. Kalman filtering

© 1981 by the American Geophysical Union.