GEOL 2207 Lecture Notes - Cloud Base, Tropopause, Lapse Rate
Document Summary
The cool downburst from one mature/dissipating storm can spread out as a gust front and trigger a daughter storm nearby where there is still fuel in form of warm humid air, processed called propagation of storm. Wind shear (change of wind speed in direction with height), in addition to warm humid boundary layer air. Allowing thunderstorm to move like vacuum cleaner, sucking fresh fuel from boundary layer, leaving cold air behind. Air cools at the dry adiabatic lapse rate as it rises. If lifted high enough to become cold enough to reach saturation, then condensation of water occurs within the air parcel. This marks cloud- base (lcl) altitude for cumuliform clouds such as thunderstorms and cumulus clouds. As the cloudy air parcel continues to rise, it still cools, but at a slower rate called the saturated or moist adiabatic lapse rate.
