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Title: Enhanced aqueous formation and neutralization of fine atmospheric particles driven by extreme cold
The prevailing view for aqueous secondary aerosol formation is that it occurs in clouds and fogs, owing to the large liquid water content compared to minute levels in fine particles. Our research indicates that this view may need reevaluation due to enhancements in aqueous reactions in highly concentrated small particles. Here, we show that low temperature can play a role through a unique effect on particle pH that can substantially modulate secondary aerosol formation. Marked increases in hydroxymethanesulfonate observed under extreme cold in Fairbanks, Alaska, demonstrate the effect. These findings provide insight on aqueous chemistry in fine particles under cold conditions expanding possible regions of secondary aerosol formation that are pH dependent beyond conditions of high liquid water.  more » « less
Award ID(s):
1927831 2029730 1927750 2012905 1927838 2029747 1927778
PAR ID:
10546820
Author(s) / Creator(s):
; ; ; ; ; ; ; ; ; ; ; ; ; ; ;
Publisher / Repository:
American Association for the Advancement of Science
Date Published:
Journal Name:
Science Advances
Volume:
10
Issue:
36
ISSN:
2375-2548
Format(s):
Medium: X
Sponsoring Org:
National Science Foundation
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