Lightning as Cleansing Agent | weatherology°
This website uses cookies to improve your user experience and for analytical purposes. By clicking the "Accept & Close" button, you agree to the storing of cookies on your device while using this site. Please see our privacy policy to learn more about how and why we use cookies.
By: Meteorologist Michael Karow
Updated: May 10th 2021

Lightning as Cleansing Agent

It's a powerful natural phenomenon that has the potential to be a deadly force of destruction. Lightning can create positive changes, too, as detailed in a previous article on lightning's role in the formation of life on Earth. A recent study also has revealed another beneficial side to lightning. A team of American scientists have uncovered how lightning works to create chemicals in the atmosphere which help to clean pollution out of the air.

The data on lightning's cleansing role was originally collected back in 2012 when a storm chasing NASA jet flew through thunderstorms over Colorado, Oklahoma, and Texas. In the lightning-filled clouds, they measured the concentration of chemicals called oxidants, the two main types being hydroxyl (OH) and hydroperoxyl (HO2). Hydoxyl, in particular, is so effective in oxidizing pollutants like methane, and allowing them to easily dissolve in rain drops and get cleared out of the air, that it has been dubbed the “detergent of the atmosphere.”

The reason why this data on lightning has only recently been reexamined is because scientists initially discounted the data, as the lightning studied was generating concentrations of oxidants in the thousands of parts per trillion, whereas previous observations had only measured lightning producing less than 10 parts per trillion. However, subsequent experiments in the lab have confirmed electricity's role in creating these larger concentrations of oxidants, than was previously thought possible.

The significance of lightning's role in cleaning atmospheric pollution worldwide, including chemicals which can exacerbate global warming, is still difficult to estimate, as this study was confined to the anvil and core of thunderstorms only over the United States. Early estimates have lightning producing anywhere from 2 to 16% of the world's hydroxyl. Subsequent studies of more thunderstorms and in more locations will be needed to improve these estimates.

lightning chemical reactions model Jenkins
Conceptual model of the chemical reactions that occur when lightning strikes in the atmosphere - [Jena Jenkins]
flight path NASA oxidants Brune
Flight path of the NASA jet through a thunderstorm, along with the measured concentration of oxidants (colors along the flight path) - [Brune et al., 2021]