A modeling study of the impact of winter-spring arctic outflow on the NO < inf> x and O < inf> 3 budgets of the North Atlantic troposphere

Document Type


Publication Date



[1] In this study, we determine the impact of winter-spring arctic outflow events on the budgets of tropospheric NOx and ozone over the North Atlantic Ocean. An updated version of the NCAR Master-Mechanism, a detailed, explicit photochemical model, is applied to trajectories representative of arctic outflow for the months of January through May. During the simulations, peroxyacetyl nitrate (PAN) mixing ratios drop by up to 270 pptv, increasing NOx levels up to 120 pptv. However, the released NOx is quickly destroyed by efficient NOx loss reactions leading to formation of HNO3 and, to a lesser extent, nitroaromatic compounds. As a result of elevated NOx, O3 levels are increased. The resulting net impact on the flux of O3 to the North Atlantic is estimated to be less than 712 Gg O3/month. While this source is similar in magnitude to estimates of ozone produced from aircraft emissions, both are small in comparison to the export of ozone from North America. Therefore, we conclude that while elevated levels of pollutants in arctic outflow increase the levels of NOx and O3 in the North Atlantic region, on a seasonal basis the impact on the budgets of NOx and O3 in this region is small. Copyright 2002 by the American Geophysical Union.

Publication Title

Journal of Geophysical Research Atmospheres