Water evaporates all around us all the time, whether it’s sweat cooling our skin or the dew vanishing in the morning sun. Scientists have been studying this process and recently found something surprising.
They noticed that water held in a sponge-like material called a hydrogel was evaporating faster than expected, even when it didn’t receive enough heat to explain the rapid evaporation. This extra evaporation was much more than what scientists thought was possible.
A team at MIT investigated this and discovered something incredible. They found that, in certain situations, when water meets air, light can make water evaporate directly, without needing heat.
This happens more efficiently than evaporation caused by heat. In their experiments, water was held in a hydrogel, but they believe this could happen in other situations too.
Result from the testing
The scientists tested different colors of light on the water surface, one after the other. They did this by putting a container of water-filled with the hydrogel on a scale and measuring how much water evaporated.
The team also checked the temperature above the hydrogel. They made sure the lights didn’t produce extra heat.
The researchers discovered that the evaporation changed with different colors of light and was highest with the green light.
This connection between color and evaporation isn’t related to heat, which suggests that the light itself is causing some of the water to evaporate.
