Natural Phenomenon / 4 min read / 08 May 2021
Nah, right, We even never thought that something so common as “lightning” can create such an impact on the Atmosphere.
Lightning breaks down nitrogen and oxygen molecules in the atmosphere and creates reactive chemicals that affect greenhouse gases. Now a team of atmospheric lightning chemists and scientists has discovered that lightning and, surprisingly, invisible discharges that cannot be seen by cameras or the naked eye produce extreme amounts of the hydroxyl radical - OH - and the hydroperoxyl radical – HO2.
The data came from a device in a plane that flew over Colorado and Oklahoma in 2012, looking at the chemical changes that storms and lightning are causing in the atmosphere. "With the help of a great college intern," William H Brune (distinguished professor of meteorology at Penn State.) said, "we were able to combine the huge signals observed by our device flying through storm clouds with the measurement of lightning from the ground."
Visible lightning occurs in a part of the anvil in a plane near the core of the storm. "Throughout history, people have only been interested in lightning because of what they could do on earth," Brune said. "There is now a growing interest in weaker electric shocks during thunderstorms that lead to lightning." Most lightning never hits the ground, and lightning that remains in the clouds is especially important for affecting ozone and important greenhouse gases in the upper atmosphere.
It has been known that lightning can break down water to form hydroxyl and hydroperoxyl, but this process has never been observed in storms before. Brune's team was initially confused that their device detected high levels of hydroxyl and hydroperoxyl in areas of the cloud where no lightning was visible from the plane or the ground. Experiments in the laboratory have shown that a weak electric current, much less energetic than visible lightning, can produce the same components. While scientists have found hydroxyl and hydroperoxyl in areas with weak lightning, they have found little evidence of ozone and no evidence of nitric oxide, which requires the creation of visible lightning.
If invisible lightning routinely occurs, then hydroxyl and hydroperoxyl, which generate these electrical events, must be included in atmospheric models.
The hydroperoxyl radical, also known as the hydrogen superoxide, is the protonated form of superoxide with the chemical formula HO₂. This species plays an important role in the atmosphere and as a reactive oxygen species in cell biology.