GEOG 1112 Lecture Notes - Lecture 11: Fluid Parcel, Rain Shadow, Advection
Document Summary
Lifting mechanisms: convection, orographic uplift, convergence, frontal lifting, we will also see how stability (and lapse rates) plays a role in how easily an air parcel is displaced. Mechanisms that lift air: localized convection: occurs when differential heating at the surface causes air to lift. The air expands and cools as it lifts, causing cloud development: convergence: occurs when there is a horizontal movement of air into a region. When air converges along the earth"s surface, it is forced to rise since it cannot go downward: frontal lifting: occurs when two air masses converge at the front. This can occur when cold air advances towards warm air (cold front) or when warm air advances towards cold air (warm front). Clouds develop as a result of these two situations: orographic uplift: occurs when a mass of air is deflected over and/or around terrain, usually a hill or mountain. This upward movement of air results in adiabatic cooling.