What if a molecule existed that could take atmospherics pollutants (known for disrupting and causing harm to the Earth’s ozone layer and rising global temperatures) and turn them into particles that could potentially have a cooling effect on the planet’s climate? While taking a look at what are known as Criegee molecules, researchers have found that these naturally occurring biradicals are much more efficient than previously thought.
Named after Rudolf Criegee, a German chemist who first brought these naturally occurring biradicals to light, the Criegee intermediate (as it went on to be called) is a “reactive molecule missing two chemical bonds” that can combine with particles of ozone to form less threatening compounds. Existing naturally as an alkene—an organic compound commonly released from much of the world’s thriving ecosystems—the Criegee intermediate “could oxidise sulphur dioxide, which eventually turns into sulphuric acid, which has a known cooling effect,” explains Carl Percival, one of a number of authors of the study recently reported and published in the journal Science.
Wanting to take a closer look at these Criegee intermediates, researchers recently set out to discover if these biradicals could be produced in a lab setting.
Researchers from the Universities of Manchester and Bristol, as well as the Sandia National Laboratories in the United States, set out to find if they could successfully replicate these intermediates. Because the reaction of the Criegee intermediate and a pollutant occur so rapidly in the environment, scientists needed to slow down the process in order to get a better look. However, in order to get their hands on an intermediate, they had to make one for themselves. They accomplished this by shining a powerful laser light on a compound of diiodomethane, forcing it to break off two bonds—thus giving them the biradical they needed.
They then took the newly formed Criegee intermediate and added known pollutants, like sulphuric dioxide, nitric dioxide, water, or nitric oxide into the mix. What happened next shocked even them. When combined with nitric dioxide and sulphuric dioxide, the intermediate responded quicker than they expected, leaving a practically immediate cooling effect.
While this new evidence has presented a breakthrough for many looking for more efficient ways to combat the effects of global warming, it is clear that science can in no way be a substitute for what nature does on its own. The Earth’s ecosystem puts out 90 percent of the alkenes that produce these cooling intermediates, a feat not easily matched by science. “The ecosystem is negating climate change more efficiently than we thought it was,” states Percival.
The solution, according to Alan Robock a climate scientist at Rutgers University, lies not in establishing science as a viable option to combat climate change but in preserving the environment: “The solution to global warming is mitigation, it’s not geoengineering…If anybody thinks this s a solution to global warming, it will take away that push there is now toward mitigation.” What it all comes down to is preserving and taking care of the planet’s natural ecosystems and its natural way of balancing itself, and not to get distracted by breakthroughs in science like this. While it does offer great insight, the most significant thing to take from this study is the importance of taking care of our most precious ecosystems.
Photo Credit: lbl.gov/Science-Articles/Archive/assets/images/2005/Jan-20/green_plants.jpg