Publication Date:
2018-07-13
Description:
Iodine monoxide and ozone measurements were taken using long-path differential optical absorption spectroscopy along the Gulf of Mexico coast near Galveston, Texas, in spring/summer of 2016. During the eight-week campaign, half of the days were characterized by O3 between 12 and 25 ppb. These air masses coincided with onshore flow and had measurable levels of IO, with an average daily maximum around 0.8 ppt and values as high as 2 ppt. The presence of IO indicates the influence of iodine chemistry which catalytically destroys O3. Using observed IO and NO2 levels, along with model HO2 data, an O3 destruction rate between 1.5 and 2 ppb/day was calculated. Assuming a background O3 level of 30 ppb, it is very likely that iodine chemistry is responsible for destroying enough O3 along a 10-day back trajectory through the Gulf of Mexico to explain the low mixing ratios frequently experienced along the Texas coast. ©2018. American Geophysical Union. All Rights Reserved.
Print ISSN:
0094-8276
Electronic ISSN:
1944-8007
Topics:
Geosciences
,
Physics
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