HOx Chemistry and Ozone Production During INTEX-B
Abstract
Measurements of OH and HO2 (collectively called HOx) were made with the Airborne Tropospheric Hydrogen Oxides Sensor (ATHOS) as part of a much larger measurement suit from the NASA DC-8 aircraft during INTEX-B in spring 2006. This mission, which was conducted mainly over South United State and Mexico (Phase- A) and West Pacific Ocean (Phase-B), was an excellent test of oxidation chemistry in pollution plumes and clean air throughout the troposphere. Measured HOx are compared with the calculations from a box model constrained to other in-situ measurements of long-lived chemicals. On average, both the measured OH and HO2 agree well with the calculations within 15%, which is similar to the results during INTEX-A, another aircraft mission conducted over the continental of the United States, except above 8 km where the model significantly under-predicted HO2 during INTEX-A. The main HOx production was the O(1D)+H2O reaction and main HOx loss was the HO2+HO2 and HO2+RO2 reactions. During Phase-A, there was a net O3 production rate (0.1-1 ppb/hr) below 4 km, while during Phase-B a slight net O3 loss rate (0.1-0 ppb/hr) below 7 km and a slight net O3 production rate (0-0.1 ppb/hr) above 7 km were observed. HOx behavior under different conditions will be discussed.
- Publication:
-
AGU Fall Meeting Abstracts
- Pub Date:
- December 2007
- Bibcode:
- 2007AGUFM.A42A..04R
- Keywords:
-
- 0340 Middle atmosphere: composition and chemistry;
- 0345 Pollution: urban and regional (0305;
- 0478;
- 4251);
- 0365 Troposphere: composition and chemistry;
- 0368 Troposphere: constituent transport and chemistry