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<br />diagram. This highly simplified, fast, numerical simulation of parcel <br /> <br />buoyancy provides a systematic measurement tool to determine the relative <br /> <br />potential for convective cloud growth and its intensity. These character- <br />,istics of convection are diagnosed by the model in real~time using the <br /> <br />, <br />~ <br /> <br />rawinsonde data for model initialization. These data are analyzed in terms <br /> <br />of cloud properties such as cloud-base height, cloud-top height, maximum <br />vertical velocity of the parcel, and other quantitative properties which <br /> <br />may be compared for different soundings and locations to describe the <br />natural variability of potential for convective cloud growth. Due to the <br /> <br />simple and incomplete microphysics and dynamics of these models, care must <br /> <br />be taken in the interpretation of results. Meaningful comparisons between <br />model-diagnosed cloud properties and those of a specific observed cloud <br /> <br />are difficult, if not impossible, due to the complex three-dimensional, <br /> <br />, <br />time-dependent nature of cloud growth. Nevertheless, useful thermodynamic <br />characteristics of individual clouds within a field of clouds may be <br /> <br />obtained from model analyses which quantify the potential for convection <br />in a given area and time. Such results may be interpreted as general <br />thermodynamic characteristics which may be useful for examining the <br /> <br />natural variability of convective potential. In this report, model <br /> <br />results are studied from this broader context. <br /> <br />The atmosphere's capacity to support convective cloud development, as <br /> <br />defined by the cloud depth diagnosed by the model, is probably the most <br /> <br />useful information available from one-dimensional, steady-state cloud <br />models (Silverman, 1976). This "dynamic potential" for convective cloud <br />growth is di rectly rel ated to the pos it ive area observed on a thermo- <br />dynamic diagram. Due to the limited ability of one-dimensional, <br /> <br />8 <br />