Dan Kedmey writes: On a typical sunny day in the Amazon, 20 billion metric tons of water flow upward through the trees and pour into the air, an invisible river that flows through the sky across a continent.

“This river of vapor that comes up from the forest and goes into the atmosphere is greater than the Amazon River,” says Antonio Donato Nobre (TED Talk: The magic of the Amazon: A river that flows invisibly all around us). Nobre is a senior researcher at Brazil’s National Institute of Amazonian Research. And in his opinion, the most remarkable thing about the Amazon — even more than its 4,000 miles of river or its hundreds of billions of trees — is that it’s essentially a massive, solar-powered sprinkler system, spritzing water across a continent. If this were a man-made system, Nobre says, it would be the envy of the world. Here’s why Nature is the most badass engineer of all.

Every tree is a silent geyser. Through a process called transpiration, a large tree in the Amazon can release 1,000 liters of water into the atmosphere in a single day. “There is a frantic evaporation taking place here,” Nobre says. He likens the force to a geyser spouting water into the air, but “with much more elegance.” After all, geysers draw their power from the scalding heat of magma, while trees only need to bask in the sunlight to release their invisible steam. Plus, they have the sheer force of numbers; hundreds of billions of trees in the jungle release as many as 20 billion metric tons of water into the atmosphere every day. That means that while the Amazon, which pours 17 billion tons of water into the Atlantic Ocean a day, may be the largest river on earth — it’s still exceeded by the airborne river drifting above the canopy of the trees. [Continue reading…]