Determination of the Effective Imaginary Term of the Complex Refractive Index of Atmospheric Dust by Remote Sensing: The Diffuse-Direct Radiation Method

Abstract

A unique and promising method is outlined for determining the complex part of the index of refraction of atmospheric dust by utilizing measurements of diffuse and direct solar radiation. The solution requires comparison of measurements of the ratio of diffuse to direct solar radiation with theoretical calculations of the same values. A knowledge of the ground albedo is necessary for the solution. The ground albedo may, in fact, also be determined from the measured ratios, but the solution in this case tends to he more sensitive to measurement than when the ground albedo is known. Abstract A unique and promising method is outlined for determining the complex part of the index of refraction of atmospheric dust by utilizing measurements of diffuse and direct solar radiation. The solution requires comparison of measurements of the ratio of diffuse to direct solar radiation with theoretical calculations of the same values. A knowledge of the ground albedo is necessary for the solution. The ground albedo may, in fact, also be determined from the measured ratios, but the solution in this case tends to he more sensitive to measurement than when the ground albedo is known.