Researchers discovered that light can cause evaporation of water from a surface without the need for heat. This 'photomolecular effect' could be important for understanding climate change and for improving some industrial processes.
The authors say their study suggests that the effect should happen widely in nature -- everywhere from clouds to fogs to the surfaces of oceans, soils, and plants -- and that it could also lead to new practical applications, including in energy and clean water production."I think this has a lot of applications," Chen says."We're exploring all these different directions.
The effect is strongest when light hits the water surface at an angle of 45 degrees. It is also strongest with a certain type of polarization, called transverse magnetic polarization. And it peaks in green light -- which, oddly, is the color for which water is most transparent and thus interacts the least.
"Those experiments are based on satellite data and flight data," Chen explains."They fly an airplane on top of and below the clouds, and there are also data based on the ocean temperature and radiation balance. And they all conclude that there is more absorption by clouds than theory could calculate. However, due to the complexity of clouds and the difficulties of making such measurements, researchers have been debating whether such discrepancies are real or not.