What is nocturnal oxidation?

Thanks to the work of researchers who reproduce atmospheric chemistry in the laboratory, we are gradually learning more about cloud formation and climate. A joint study by scientists from Ircelyon (CARE team) and the University of Toronto in Canada has just been published in the journal Science Advances. This work reveals that light is not necessary to oxidise organic aerosols suspended in the atmosphere. Instead, the presence of humidity is enough to trigger the oxidation process, which is referred to as nocturnal oxidation. This discovery is crucial for assessing the effects of atmospheric phenomena and air pollution.
An article in CNRS Chimie is devoted to this study. You can read it here.

Humidity drives spontaneous OH oxidation of organic particles
Maria Angelaki, D. James Donaldson, Sébastien Perrier, Matthieu Riva & Christian George
Science Advances 2025
DOI: 10.1126/sciadv.adx4507