Human Activity, Natural Phenomena Aerosols May Intensify Thunderstorms
MIT researchers have found the reason why aerosols caused more intense thunderstorms in recent research.
The research indicated that, based on their observations of Earth's atmosphere, thunderstorms are often stronger where high concentrations of aerosols are present in a specific area, such as tropical regions.
Up until now, it's been known that aerosols and thunderstorms were somehow connected, however, the reason behind the science was not clear. The researchers drew upon a new mechanism called the “humidity-entrainment", where aerosols increase humidity in the air surrounding clouds.
“It’s possible that, by cleaning up pollution, places might experience fewer storms,” Tim Cronin, assistant professor of atmospheric science at MIT said. “Overall, this provides a way that humans may have a footprint on the climate that we haven’t really appreciated much in the past,” he continued.
Aerosols, defined as any particles that are too tiny to see with naked eye in the air, are generated by both human activity and natural phenomena that can in the long run have damaging effects on the environment. Burning of biomass, combustion in various vehicles and factories; volcanic eruptions releasing ashes, sea spray, and dust storms are some examples of these processes.
In usual cases, the surfaced particles can help clouds to form, serving as a base for water vapor to condense and create individual droplets and merge afterward. The merged droplets, forming bigger droplets in size can eventually turn into rain. However, when these tiny particles are highly condensed, the droplets they form in turn don't merge that easily, causing thunderstorms.
The researchers tested their possible reason behind how intensified thunderstorms are generated and ran different cloud simulations, increasing the concentration of water droplets in clouds. Later, they suppressed the processes which stimulated the previously proposed two mechanisms and checked if thunderstorms still increased when aerosol concentrations emerged.
When the processes were shut down, the stimulation still created more intense thunderstorms with higher aerosol concentrations.
“That told us these two previously proposed ideas weren’t what were producing changes in convection in our simulations,” Abbott said. “We’ve provided a new mechanism that should give you a reason to predict stronger thunderstorms in parts of the world with lots of aerosols,” added.