An analysis of statistical characteristics of stratus and stratocumulus over eastern Pacific

Observational measurements of cloud base, top, thickness, fraction, and liquid water path (LWP) are analyzed to study the macro- and micro-physical properties of stratus and stratocumulus over the eastern Pacific. It is found that the increase in liquid water content with height in cloud is significantly less than the adiabatic rate. The variations of cloud base and top both contribute to the variation of cloud thickness that approximately fits a normal distribution better than either cloud base or top. Because the distribution of LWP depends on the intervals of cloud fraction (or other environmental variables, for example, relative humidity), the determination of cloud fraction from the mean LWP alone would introduce large uncertainties particularly when LWP is large.