INDIRECT MEASUREMENTS OF ATMOSPHERIC TEMPERATURE PROFILES FROM SATELLITES: I. INTRODUCTION

Abstract Artificial earth satellites offer a unique opportunity to exploit the possibility of deducing temperature profiles on a global scale from measurements of radiance in several narrow spectral intervals in a strongly absorbing band of an atmospheric gas whose mixture is uniform. In the earth's atmosphere the 4.3-micron and 15-micron bands of carbon dioxide and the 5-mm. band of oxygen may be used; only the 15-micron band is considered in detail, although the procedures are applicable to the other bands. The problem considered is the numerical solution of the integral form of the radiative transfer equation from measurements in a finite set of spectral intervals. It is shown that, by a suitable approximation of the Planck radiance, the radiative transfer equation can be reduced to an integral equation of the first kind. After a discussion of the kernel, which is associated with the transmittance of the gas, the equation is changed to a finite set of equations which is amenable to numerical solution. ...