Nitrate radical

From Glossary of Meteorology

nitrate radical

Free radical, formula NO3, formed from the reaction of nitrogen dioxide with ozone.

NO3 has a very strong optical absorption in the visible portion of the spectrum. Absorption of solar radiation in this region leads to photodissociation and thus a very short atmospheric lifetime during the day. However, at night NO3 can build up to substantial levels and react with some families of organic molecules, allowing oxidation chemistry that would not otherwise occur at night. Nitrate reacts to form dinitrogen pentoxide, which can be taken up into aqueous droplets and increase acidity. Optical absorption has been used to detect NO3 in the atmosphere.

Copyright 2022 American Meteorological Society (AMS). For permission to reuse any portion of this work, please contact Any use of material in this work that is determined to be “fair use” under Section 107 of the U.S. Copyright Act (17 U.S. Code § 107) or that satisfies the conditions specified in Section 108 of the U.S.Copyright Act (17 USC § 108) does not require AMS’s permission. Republication, systematic reproduction, posting in electronic form, such as on a website or in a searchable database, or other uses of this material, except as exempted by the above statement, require written permission or a license from AMS. Additional details are provided in the AMS Copyright Policy statement.