Connect with us

Hi, what are you looking for?

Hydroxyl, a free radical composed of one hydrogen atom and one oxygen atom, reacts with methane in the atmosphere, breaking it into its component parts and lessening how much it adds to global warming. The supply of hydroxyl is remaining constant, but for how long?

Climate Change

Free Radicals In Atmosphere “Eat” Methane Emissions

Hydroxyl, a free radical composed of one hydrogen atom and one oxygen atom, reacts with methane in the atmosphere, breaking it into its component parts and lessening how much it adds to global warming. The supply of hydroxyl is remaining constant, but for how long?

Free Radicals! Sounds like a sign one might have seen outside Berkeley in the 60s, doesn’t it? But we are not talking about unwashed hippies here. Today’s topic is OH, or hydroxyl as it is known the scientific community. It is a molecule left over when sunlight breaks down water vapor in the atmosphere. What makes it a free radical is an extra electrical charge, meaning it can easily bond with other molecules — like methane.

hydroxyl radical and methane

Credit: Wikipedia

We know that methane can be a powerful greenhouse gas that contributes significantly to a warmer planet. Whether it comes from wells or cow stomachs, it is estimated to trap as much as 12 times more heat than carbon dioxide. Now scientists at NASA have discovered that hydroxyl acts as a detergent, breaking down methane in the atmosphere then recycling itself so it can repeat the process again.

The hydroxyl radical, a molecule made up of one hydrogen atom and one oxygen atom with a free electron, is one of the most reactive gases in the atmosphere and regularly breaks down other gases, effectively ending their lifetimes. In this way OH is the main check on the concentration of methane. The research has been published by the Journal of Geological Research — Atmospheres.

“OH concentrations are pretty stable over time,” says lead author Julie Nicely of the Goddard Space Flight Center in Greenbelt, Maryland. “When OH reacts with methane it doesn’t necessarily go away in the presence of other gases, especially nitrogen oxides (NO and NO2). The breakdown products of its reaction with methane react with NO or NO2 to reform OH. So OH can recycle back into the atmosphere.” The research examined data on atmospheric gases from 1980 through 2015.

One factor contributing to the amount of hydroxyl molecules in the atmosphere is a widening of the tropical zones over time at the rate of about 0.5 to 1 degree of latitude per decade. Scientists believe the wider tropical zones may be related to new wind patterns as the air over Equator gets warmer. Wider zones mean more moist air is available for the creation of hydroxyl molecules. Think of it as a buffering process in which the Earth attempts to offset the negative effects of methane by breaking it down into less harmful components.

While that might give comfort to those who assume the Earth will somehow shrug off the insults visited upon it by humanity, anyone who has ever dabbled in organic chemistry knows that at some point, buffering reaches a limit. Once that happens, things go to hell in a hand basket very quickly. In other words, this discovery is good news but it is no bulwark against humans continuing to use the Earth as a communal toilet.

“The absence of a (downward) trend in global OH is surprising,” says Tom Hanisco, an atmospheric chemist at Goddard who was not involved in the research. “Most models predict a ‘feedback effect’ between OH and methane. In the reaction of OH with methane, OH is also removed. The increase in NO2 and other sources of OH, such as ozone, cancel out this expected effect.”

He then issues the same cautions financial advisers do when advising clients — past performance is no guarantee of future performance. As the atmosphere continues to evolve with global climate change, OH levels may not continue to recycle in the same way in the future.

Nicely says the value of the research is its ability to help climate scientists fine tune and update the assumptions about how the climate is affected by various inputs, including human activity. “This could add clarification on the question of will methane concentrations continue rising in the future? Or will they level off, or perhaps even decrease? This is a major question regarding future climate that we really don’t know the answer to,” she says.

Appreciate CleanTechnica’s originality? Consider becoming a CleanTechnica member, supporter, or ambassador — or a patron on Patreon.
Have a tip for CleanTechnica, want to advertise, or want to suggest a guest for our CleanTech Talk podcast? Contact us here.

New Podcast: How NVIDIA Is Bringing Autonomy To Automakers

Written By

Steve writes about the interface between technology and sustainability from his homes in Florida and Connecticut or anywhere else the Singularity may lead him. You can follow him on Twitter but not on any social media platforms run by evil overlords like Facebook.


#1 most loved electric vehicle, solar energy, and battery news & analysis site in the world.


Support our work today!


Power CleanTechnica: $3/Month

Tesla News Solar News EV News Data Reports


EV Sales Charts, Graphs, & Stats


Our Electric Car Driver Report

30 Electric Car Benefits

Tesla Model 3 Video

Renewable Energy 101 In Depth

solar power facts

Tesla News

EV Reviews

Home Efficiency

You May Also Like

Climate Change

BlackRock Investment Institute believes doing nothing to create a net zero economy could reduce global economic output by 25% 20 years from now.

Cleantech News

Grimes has dropped her new WarNymph collection in collaboration with Nifty Gateway, which is a marketplace for buying and selling Nifties — “digital items...

Climate Change

The winter storm has affected most of the U.S. South, and Texas has been in the spotlight thanks to its disastrous leadership — blaming...

Cleantech News

Johnson Controls, a company that produces fire, HVAC, and security equipment for buildings, announced today that it joined The Climate Pledge, which is a...

Copyright © 2021 CleanTechnica. The content produced by this site is for entertainment purposes only. Opinions and comments published on this site may not be sanctioned by and do not necessarily represent the views of CleanTechnica, its owners, sponsors, affiliates, or subsidiaries.