Positive Area

In meteorology, convective available potential energy (CAPE), sometimes, simply, available potential energy (APE), is the amount of energy a parcel of air would have if lifted a certain distance vertically through the atmosphere. CAPE values are valuable in predicting severe weather.
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The area on a sounding representing the layer in which a lifted parcel would be warmer than the environment; thus, the area between the environmental temperature profile and the path of the lifted parcel. See sounding

Positive area is a measure of the energy available for convection ; see CAPE .