AI Article Synopsis
- Aerosol particles and their interactions with clouds create significant uncertainty in the climate system, affecting size, chemical makeup, and radiative properties.
- During the early moments after cloud droplet formation, aerosols can generate a significant burst of hydroxyl radicals (OH), ranging from 0.1 to 3.5 micromolar, influenced by near-UV light.
- This burst originates from previously unrecognized reactions between iron(II) and peracids, potentially increasing total OH levels in droplets significantly, by up to five times compared to known sources, thereby enhancing the effects of clouds on aerosol properties.
Article Abstract
Aerosol particles and their interactions with clouds are one of the most uncertain aspects of the climate system. Aerosol processing by clouds contributes to this uncertainty, altering size distributions, chemical composition, and radiative properties. Many changes are limited by the availability of hydroxyl radicals in the droplets. We suggest an unrecognized potentially substantial source of OH formation in cloud droplets. During the first few minutes following cloud droplet formation, the material in aerosols produces a near-UV light-dependent burst of hydroxyl radicals, resulting in concentrations of 0.1 to 3.5 micromolar aqueous OH ([OH]). The source of this burst is previously unrecognized chemistry between iron(II) and peracids. The contribution of the "OH burst" to total OH in droplets varies widely, but it ranges up to a factor of 5 larger than previously known sources. Thus, this new process will substantially enhance the impact of clouds on aerosol properties.
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| http://www.ncbi.nlm.nih.gov/pmc/articles/PMC6494489 | PMC |
| http://dx.doi.org/10.1126/sciadv.aav7689 | DOI Listing |
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