The expansion allows more room for the air molecules inside the parcel to move about. More room means less collisions between the molecules. Less KE means cooler temperatures. This higher pressure causes the air parcel to compress. The compression allows less room for the air molecules inside the parcel to move about.
Less room means more collisions between the molecules.
More KE means warmer temperatures. Environmental Lapse Rate Refer to the Math Quiz Help . How Things Work - Info on heat transfers. Air Temperature - Another professor's notes. Plotting Isopleths - Test your skills on this interactive map.