The Size Distribution of Cumulus Clouds as a Function of Cloud Amount

Abstract

Small cumulus clouds over the ocean were observed photographically using air liners in the periods of AMTEX '74 and '75. These photographs were analyzed to determine the size distributions of cumulus clouds as a function of cloud amount by the trigonometric method. It was found that the size distributions are represented by the exponential distribution N=a⋅exp(-bD), where N is the number concentration and D is the diameter. The coefficients a and b are expressed exponentially as functions of cloud amount.
The flatness of convective cells were also analyzed. It was shown that the cell diameter has a linear relation to its depth, and that the cell flatness has a linear relation to the reciprocal of its depth.