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<br />Recent analyses by Simpson et al. (1982) using the three- <br />dimensional model of Schlesinger (1975) showed the important contri- <br />bution of shear to cloud-environment interactions in the tropics <br />using GATE sounding data. Simpson found that different profiles of <br />shear produced changes in the dynamc entrainment, detrainment, and <br />local cloud-environment stability by changing the amount of low <br />equivalent potential temperature air brought to the surface from <br />mid-levels by downdrafts. Simpson et ale (1982) suggest the need for <br />remote observations that study the cloud and its environmental flow <br />simulaneously to better describe the controls of convection. <br /> <br />Simulations of meso-Q scale (250-2500 km) upper-tropospheric <br />features associated with MCC using a primative equation model clearly <br />show the interaction of moist convection with large-scale flow fields <br />at mid-latitudes (e.g., Maddox et al. (1981). These simulations in <br />the environment of an MCC using the Drexel-NCAR mesoscale primative <br />equation model (Kreitzberg and Perky, 1977) showed the development of <br />a mesoscale divergence field with values reaching 16 x 10-5/s at <br />200 mb above the MCC and a jet streak north of the MCC. Mesoscale <br />band-pass analyses of rawinsonde data diagnosed the important meso- <br />scale feature which was predicted only in moist simulations of the <br />model. Vertical motion fields of the moist simulation showed a <br />mesoscale core of lifting of 32 cm/s over the MCC at the 500 mb <br />level. Maddox et al. (1981) concluded that the deep moist convective <br />processes a~sociated with the MCC produced the region of large meso- <br />scale lifting. These simulations further suggest the need for com- <br />prehensive mesoscale rawinsonde observations to study the life-cycle <br />of mesoscale convective systems. <br /> <br />25 <br />