Scientists have shown that a new molecule in the earth’s atmosphere has the potential to play a significant role in off-setting global warming by cooling the planet.
In a breakthrough paper published in Science, researchers from the University of Manchester , the University of Bristol and Sandia National Laboratories report the potentially revolutionary effects of Criegee biradicals.
These invisible chemical intermediates are powerful oxidisers of pollutants such as nitrogen dioxide and sulphur dioxide, produced by combustion, and can naturally clean up the atmosphere.
Although these chemical intermediates were hypothesised in the 1950s, it is only now that they have been detected. Scientists now believe that, with further research, these species could play a major role in off-setting climate change.
The detection of the Criegee biradical and measurement of how fast it reacts was made possible by a unique apparatus, designed by Sandia researchers, that uses light from a third-generation synchrotron facility, at the Lawrence Berkeley National Laboratory’s Advanced Light Source.
The intense, tunable light from the synchrotron allowed researchers to discern the formation and removal of different isomeric species - molecules that contain the same atoms but arranged in different combinations.
The researchers found that the Criegee biradicals react more rapidly than first thought and will accelerate the formation of sulphate and nitrate in the atmosphere. These compounds will lead to aerosol formation and ultimately to cloud formation with the potential to cool the planet.
The formation of Criegee biradicals was first postulated by Rudolf Criegee in the 1950s. However, despite their importance, it has not been possible to directly study these important species in the laboratory.
In the last 100 years, Earth’s average surface temperature increased by about 0.8 °C with about two thirds of the increase occurring over just the last three decades.
Most countries have agreed that drastic cuts in greenhouse gas emissions are required, and that future global warming should be limited to below 2.0 °C (3.6 °F).