Time travels to the Amazon to reveal the fungi that creates the clouds:
The clouds in the Amazon, just like everywhere else, consist of water vapor clinging to tiny clumps of carbon compounds. In forested areas, the carbon compounds are byproducts of plants’ metabolism; in populated areas, they are often from human pollution. Most of the time, atmospheric chemists can see the carbon clumping taking place; when the microscopic bits reach a certain size, they are able to attract and hold water. In the Amazon, the clumps seem to appear out of nowhere, nearly fully formed.
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Max Planck graduate student Christopher Pohlker traveled to a pristine stretch of forest in Brazil to see if he could solve the riddle…. To figure out the chemical make-up of those particles, he and his colleagues brought the squares to Lawrence Berkeley National Laboratory in California and placed them in the facility’s synchrotron, where X-rays of varying energies were fired at the collected specks….
What the researchers found was a mix of carbon compounds, plus one other thing: potassium — and that told them a lot. Potassium salts appear to be good at getting carbon compounds to stick together.
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Pohlker, Andreae, and their colleagues ran the numbers and found that the amount of potassium particles released from microscopic fungi in the lab was indeed enough to account for the concentration of potassium they observed in their samples.
Next, they want to figure out whether this weather-making extends far beyond the jungle itself – and whether the same cycle takes place over other forests with healthy fungus populations.