thermal updrafts

Thermal updrafts are columns of warm air that rise from the earth's surface after the ground absorbs heat from the sun.

Because warm air is less dense than cool air, it ascends, creating upward currents that birds, gliders, and hang gliders exploit to gain altitude without expending energy.

Pilots and soaring birds circle within these invisible elevators to climb hundreds or thousands of feet.

Hawks ride thermal updrafts while scanning for prey below.