An Exact Method for Numerically Simulating the Stochastic Coalescence Process in a Cloud

Abstract

A computer-oriented Monte Carlo algorithm for simulating the stochastic coalescence process in a warm cloud is presented. The computational procedures used in the algorithm are rigorously derived from the fundamental premise of the stochastic model. The algorithm is more general, more accurate and more efficient than previously proposed Monte Carlo procedures; in addition, it is more exact than computations based on the stochastic coalescence equation, since it takes proper account of correlations that are artificially ignored in the derivation of that equation. The mechanics of the algorithm, its advantages and its limitations are discussed in general terms; applications to specific coalescence kernels are deferred to future publication.