It has been proposed that the properties and evolution of an aerosol can be represented by lower order moments of its size distribution without requiring additional knowledge of the distribution itself. However certain distributions, including the log-normal and modified gamma distributions widely used to represent aerosol size distributions, belong to classes of multiple distributions having identical sets of moments, a situation that brings into question the utility of moment-based representations of aerosol properties and dynamics. We compare aerosol properties and evolution for explicit dissimilar test distributions having identical moments. It is found that despite their dissimilarity (e.g., multimode vs. single mode) these distributions exhibit virtually identical physical and optical properties and dynamics. Criteria for the accuracy of aerosol properties estimated from the moments are presented. This analysis confirms the utility of moment-based representations of aerosol properties and bounds the errors resulting from this approach.
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