Effects of uncertainties in atmospheric conditions on the accuracy of concentration measurements by the differential absorption method in the 9- to 11-um and 4.6- to 5.6-um spectral ranges

摘要

Abstract: A potential source of errors at remote measurements of concentration of atmospheric gases by CO$-2$/-lasers is the incomplete knowledge of atmospheric composition and temperature during measurements. This paper gives a general expression for errors owing to approximate description of the composition of the base of a statistical atmospheric model and of separate parameters measured during laser sounding. Measurements of additional atmospheric parameters are shown can reduce considerably the uncertainty in the concentration of a gas studied. A special computer code is designed to search pairs of frequencies with minimal error in mean-path horizontal measurements by using a topographic target. The performed calculations showed that a number of referenced experiments on remote measuring of atmospheric gas concentrations by CO$-2$/-lasers were conducted at frequencies that did not provide the minimal atmospheric errors.@6