Aerosols from Pollution, Desert Storms, and Forest Fires May Intensify Thunderstorms
Observations of Earth’s atmosphere show that thunderstorms are often stronger in the presence of high concentrations of aerosols — airborne particles too small to see with the naked eye.
For instance, lightning flashes are more frequent along shipping routes, where freighters emit particulates into the air, compared to the surrounding ocean. And the most intense thunderstorms in the tropics brew up over land, where aerosols are elevated by both natural sources and human activities.
While scientists have observed a link between aerosols and thunderstorms for decades, the reason for this association is not well-understood.
Now MIT scientists have discovered a new mechanism by which aerosols may intensify thunderstorms in tropical regions. Using idealized simulations of cloud dynamics, the researchers found that high concentrations of aerosols can enhance thunderstorm activity by increasing the humidity in the air surrounding clouds.