Vol. 18, issue 03, article # 11

Abstract:

Microphysical properties of stratospheric aerosol and polar stratospheric clouds (PSCs) are simulated based on the up-to-date numerical model of formation and transformation of aerosol particles. Overall, the analyzed ensemble totals 255949 realizations and may be considered as a broad representative ensemble of stratospheric aerosol states and PSC under polar and midlatitude winter conditions of the northern hemisphere (45-90°N). The means and covariance matrices of the size distribution function (SDF) for different scenarios of PSC transformation are constructed. Possibilities of optimally parameterization of SDF and its higher-order moments are explored. It is shown that, to describe all SDF realizations with the error no larger than 5-10%, it is sufficient to use just 6 expansion coefficients, rather than specifying SDF a priori in 39 bins. Use of "foreign" vectors as a basis in parameterizations by use of other models insignificantly changes the relative errors of SDF parameterization.