Dry Adiabatic Lapse Rate

The dry adiabatic lapse rate (DALR) refers to the rate at which unsaturated air (Relative Humidity < 100%) will cool or warm as it rises or sinks respectively within the atmosphere. This rate is 10 degrees Centigrade per 1000 meters (1 kilometer).

This vector graphic helps visually illustrate this invisible weather phenomenon. One World Trade Center was added to provide scale to the image.