Uncertainty analysis of aerosol wavelength exponent measured by Raman-Mie lidars

In order to improve the measuring accuracy of aerosol wavelength exponent measured by Raman-Mie lidar(RML),the uncertainty propagation formula was used to analyze the uncertainty in detail.The uncertainties of signal,transmission ratio and assumed scattering ratio Rc were calculated based on the data measured over the west suburb of the city of Hefei.Commonly,below 6km,assuming the relative uncertainty of reference value of the scattering ratio Rc was dfined by the difference between the reference and real valves,the uncertainty of the signal and the transmission ratio was less than 30% and 4% respectively.The analytical results showed that the uncertainty of aerosol wavelength exponent could be reduced by increasing pulsed laser energy,prolonging signal collecting time and more accurately demarcating assumed Rc.