MONITORING OF AIR POLLUTION USING
MICROWAVE REMOTE SENSING

Ashok Kumar Keshari
October, 1990

The atmosphere surrounding earth surface plays an important role in the daily life of humanbeings. The increase of industry to fulfill the need of growing population, affects
the atmosphere specially the lower atmosphere which is known as “Troposphere”. The tropospheric atmosphere directly and indirectly controls the “hydrological cycle”, which
of course, affects the daily life on the earth surface. Therefore, the monitoring of tropospheric atmosphere at a regional scale is required to take preventive measures against the changes. The local monitoring of atmosphere is being carried out through balloons since early this century however, the satellite borne monitoring is not very popular due to lack of information related to microwave propagation characteristics. With this in view, we have made an effort to study the propagation characteristics of microwave and its utility as a remote sensing technique in monitoring earth’s atmosphere. In the present work, we have reviewed the electrical  properties of tropospheric atmosphere and studied its variation with altitude. We have further studied the effect of electrical properties of tropospheric atmosphere with the changes in the constituents of the atmosphere. Finally we have studied the microwave remote sensing response parameter i.e. brightness temperature over various models representative of abnormal atmosphere which are often being encountered in the industrial cities. The brightness temperature over such models show significant changes with frequency and polarization of microwave signals and the look angle of the satellite. The present work will be useful in the proper selection of microwave sensor parameters and also give some important guidelines in the interpretation of microwave remote sensing data through microwave satellite which is planned by ISRO to be launched in early 1991.