Error analysis for NO2 DIAL measurement in the troposphere.

NO₂ concentration profiles, which are important in studies of atmospheric chemistry and urban pollution, were measured by a differential absorption lidar (DIAL) based on a pair of Nd:YAG pumped dye lasers. In the experiments, 448.1 nm and 446.8 nm were used for “on” and “off” wavelengths, respectively. NO₂ concentration profiles of 0–40 ppb were obtained for altitudes between 900 and 2250 m with a 150 m range resolution. Null error, which was estimated by deviation of the null profile from zero, was <2 ppb. The statistical error, systematic error from aerosols, and error due to uncertainty of absorption cross section were <3.35 ppb, <4.44 ppb and <1 ppb, respectively. The total error was about 6.0 ppb. The estimation of aerosol backscatter and extinction error in NO₂ measurement due to inhomogeneous aerosol distribution is treated in detail. [ABSTRACT FROM AUTHOR]