NASA - National Aeronautics and Space Administration

Utilizing a previously developed CloudSat cloud object database, the sensitivity of oceanic, mature, deep convective cloud morphology to cloud-scale environmental characteristics is examined. Convective available potential energy (CAPE), aerosol optical depth, midlevel vertical velocity, and tropospheric deep shear are all used to characterize the environment. The sensitivity of various aspects of convective morphology to each one of these environmental quantities is assessed individually. The results demonstrate that clouds tend to be invigorated by higher CAPE, aerosol, and upward midlevel vertical velocity. Stronger shear tends to make clouds wider but also shallower. The relative importance of each of these and some additional environmental measures to trends in cloud morphology are compared. It is found that aerosol, deep-layer shear, and sea surface temperature tend to be the most influential environmental factors to convective morphology. The results are shown to be insensitive to the manner in which the environmental characteristics are defined. The potentially surprising weak sensitivity of cloud morphology to CAPE is discussed in detail.