A geyser and a thunderstorm share fascinating similarities. Both are composed almost entirely of fresh water and are driven upward into the atmosphere by powerful forces.
In thunderstorms over land, daytime ground heating generates updrafts and convection. Similarly, in a thermal geyser, heat from within the Earth propels water upward, often as vapor, forming what can be likened to a miniature cloud.
While a thunderstorm operates on a scale perhaps a million times larger—and a hurricane a billion times larger—geyser activity is no small phenomenon. For example, Old Faithful, one of the most famous geysers, ejects an estimated 8.21 billion gallons of fresh water annually. Some of this water remains in the atmosphere, eventually returning as rain to replenish lakes and rivers like those featured in the accompanying clips.