OPTICAL INVESTIGATIONS OF DUST STORMS DURING USSR-US EXPERIMENTS IN TAJIKISTAN, 1989

The results of studies on dust aerosol optical properties obtained dur ing the U.S.S.R.-U.S. experiment are discussed. The ground-based and a ircraft measurements carried out during the experiment allow the estim ation of characteristic values of aerosol optical depth, aerosol light -scattering coefficients, the degree of linear polarization, and aureo le phase functions for different atmospheric conditions in Central Sov iet Asia. Two dust storms were observed for which the recorded aerosol optical depth at lambda = 0.55 mu m {tau(a)(0.55)} reached 1.5 on 16 and 17 September 1989, and 3.5 on 20 and 21 September 1989. The optica l characteristics (spectral dependence of the optical depth, degree of linear polarization) were similar for two dust episodes.