Atmos. Chem. Phys. Discuss., 11, 10721-10767, 2011
© Author(s) 2011. This work is distributed
under the Creative Commons Attribution 3.0 License.
Review Status
This discussion paper has been under review for the journal Atmospheric Chemistry and Physics (ACP). Please refer to the corresponding final paper in ACP.
Reactive nitrogen, ozone and ozone production in the Arctic troposphere and the impact of stratosphere-troposphere exchange
Q. Liang1,2, J. M. Rodriguez1, A. R. Douglass1, J. H. Crawford3, E. Apel4, H. Bian1,2, D. R. Blake5, W. Brune6, M. Chin1, P. R. Colarco1, A. da Silva7, G. S. Diskin3, B. N. Duncan1, L. G. Huey8, D. J. Knapp4, D. D. Montzka4, J. E. Nielsen7,9, J. R. Olson3, S. Pawson7, A. J. Weinheimer4, and D. D. Reimer4
1NASA Goddard Space Flight Center, Atmospheric Chemistry and Dynamics Branch, Code 613.3, Greenbelt, MD 20771, USA
2Goddard Earth Sciences & Technology Center, University of Maryland, Baltimore County, Maryland, USA
3NASA Langley Research Center, Hampton,VA 23681-2199, USA
4National Center for Atmospheric Research, 1850 Table Mesa Dr., Boulder, CO 80307, USA
5University of California, 570 Rowland Hall, Irvine, CA 92697, USA
6Department of Meteorology, Pennsylvania State University, University Park, PA 16802, USA
7NASA Goddard Space Flight Center, Global Modeling and Assimilation Office, Code 610.1, Greenbelt, MD 20771, USA
8School of Earth and Atmospheric Sciences, Georgia Institute of Technology, Atlanta, GA 30332, USA
9Science Systems and Applications Inc., Lanham, Maryland, USA

Abstract. We analyze the aircraft observations obtained during the Arctic Research of the Composition of the Troposphere from Aircraft and Satellite (ARCTAS) mission together with the GEOS-5 CO simulation to examine O3 and NOy in the Arctic and sub-Arctic region and their source attribution. Using a number of marker tracers and their probability density distributions, we distinguish various air masses from the background troposphere and examine their contribution to NOx, O3, and O3 production in the Arctic troposphere. The background Arctic troposphere has mean O3 of ~60 ppbv and NOx of ~25 pptv throughout spring and summer with CO decreases from ~145 ppbv in spring to ~100 ppbv in summer. These observed CO, NOx and O3 mixing ratios are not notably different from the values measured during the 1988 ABLE-3A and the 2002 TOPSE field campaigns despite the significant changes in the past two decades in processes that could have changed the Arctic tropospheric composition. Air masses associated with stratosphere-troposphere exchange are present throughout the mid and upper troposphere during spring and summer. These air masses with mean O3 concentration of 140–160 ppbv are the most important direct sources of O3 in the Arctic troposphere. In addition, air of stratospheric origin is the only notable driver of net O3 formation in the Arctic due to its sustainable high NOx (75 pptv in spring and 110 pptv in summer) and NOy (~800 pptv in spring and ~1100 pptv in summer) levels. The ARCTAS measurements present observational evidence suggesting significant conversion of nitrogen from HNO3 to NOx and then to PAN (a net formation of ~120 pptv PAN) in summer when air of stratospheric origin is mixed with tropospheric background during stratosphere-to-troposphere transport. These findings imply that an adequate representation of stratospheric O3 and NOy input are essential in accurately simulating O3 and NOx photochemistry as well as the atmospheric budget of PAN in tropospheric chemistry transport models of the Arctic. Anthropogenic and biomass burning pollution plumes observed during ARCTAS show highly elevated hydrocarbons and NOy (mostly in the form of NOx and PAN), but do not contribute significantly to O3 in the Arctic troposphere except in some of the aged biomass burning plumes sampled during spring. Convection and/or lightning influences are negligible sources of O3 in the Arctic troposphere but can have significant impacts in the upper troposphere in the continental sub-Arctic during summer.

Citation: Liang, Q., Rodriguez, J. M., Douglass, A. R., Crawford, J. H., Apel, E., Bian, H., Blake, D. R., Brune, W., Chin, M., Colarco, P. R., da Silva, A., Diskin, G. S., Duncan, B. N., Huey, L. G., Knapp, D. J., Montzka, D. D., Nielsen, J. E., Olson, J. R., Pawson, S., Weinheimer, A. J., and Reimer, D. D.: Reactive nitrogen, ozone and ozone production in the Arctic troposphere and the impact of stratosphere-troposphere exchange, Atmos. Chem. Phys. Discuss., 11, 10721-10767, doi:10.5194/acpd-11-10721-2011, 2011.
Search ACPD
Discussion Paper
Final Revised Paper