Physics Commons^™

The Effect Of Stochastic Cloud Structure On The Icing Process, A. R. Jameson, Alexander Kostinski

Department of Physics Publications

Current understanding of the icing process through collisions between a surface and supercooled cloud droplets is based upon two factors. First, for a given temperature, when the cloud liquid water content, W, exceeds a critical value, w_c (the Schumann–Ludlam limit), the ice that collects, whether on the surface of a hailstone or on the wing of an aircraft, changes from lower densities to values close to that of water. Second, it is assumed that cloud droplets are dispersed in space as uniformly as randomness allows (“Poissonian” clouds).

It is now becoming well established, however, that clouds are not Poissonian. …

On The Spatial Distribution Of Cloud Particles, Alexander Kostinski, A. R. Jameson

Department of Physics Publications

Recent studies have led to the statistical characterization of the spatial (temporal) distributions of cloud (precipitation) particles as a doubly stochastic Poisson process. This paper arrives at a similar conclusion (larger-than-Poissonian variance) via the more fundamental route of statistical physics and significantly extends previous findings in several ways. The focus is on the stochastic structure in the spatial distribution of cloud particles.

A new approach for exploring the stochastic structure of clouds is proposed using a direct relation between number density variance and the pair correlation function. In addition, novel counting diagrams, particularly useful for analyzing counts at low data …

Fluctuation Properties Of Precipitation. Part Vi: Observations Of Hyperfine Clustering And Drop Size Distribution Structures In Three-Dimensional Rain, A. R. Jameson, Alexander Kostinski

Department of Physics Publications

In past work it is argued that rain consists of patches of coherent, physical drop size distributions passing in an unpredictable fashion for an unknown duration over a sensor. This leads to the detection both of correlations among drops and of clustering. While the analyses thus far support this characterization, in this final paper in this series, techniques are developed demonstrating that clustering of drops of a specific size in rain is occurring even on scales as small as a few centimeters. Moreover, using video disdrometer data processed to achieve high temporal resolution, it is shown that drops of different …