Newly Discovered Particle Could Help Cool Earth
Elusive molecules in the Earthâ€™s atmosphere may be helping to cool the planet more efficiently than scientists previously thought, a new study suggests. They are called Criegee intermediates, or Criegee biradicals (named after the German chemist Rudolf Criegee), and are short-lived molecules that form in the Earthâ€™s atmosphere when ozone reacts with alkenes (a family of organic compounds). While scientists have known about the intermediates for decades, they haven’t been able to directly measure how the molecules react with other atmospheric compounds, such as the pollutants nitrogen dioxide and sulfur dioxide, until now.
Researchers used a new method to create Criegee intermediates in the lab, and then reacted them with several atmospheric compounds. They found that the reactions with the pollutants could produce aerosols, tiny particles that reflect solar radiation back into space, much more quickly than previously assumed. Given that 90 percent of the alkenes in the atmosphere that produce these intermediates come from Earth’s ecosystems, the results suggest that “the ecosystem is negating climate change more efficiently than we thought it was,” said study co-author Carl Percival.