MAY 11, 2017

The rain that never reaches the ground

WRITTEN BY: Kathryn DeMuth Sullivan

What happens to the rain that doesn't ever reach the ground? This may sound like a trick question, but it's not. Yes, a lot of rain that never sinks into the earth falls over the ocean, but even rain that does fall over land sometimes doesn't make it to the ground because it evaporates as it goes through warm air. Although it is difficult to measure how much rain exactly evaporated in the sky as its falling, computer simulations have estimated that as much as 40% of rain gets evaporated even before it falls to the earth!

In places where that rain does reach the surface, trees often act as umbrellas blocking the rain from going to the ground, and approximately 15% of the rain that settles on trees' leafs gets evaporated into the atmosphere before it can even drip down to the soil where the trees can actually reabsorb it. That 15% plus the 40% that gets evaporated as it falls through the sky makes up more than half of the rain that clouds produce, resulting in the equivalent of fifteen Amazon Rivers rejoining the sky before they even hit the ground. Who knew?