1Institute for Climate and Atmospheric Science, School of Earth & Environment, University of Leeds, UK
2Atmospheric Chemistry Division, NCAR, Boulder, CO, USA
3UPMC Univ. Paris 06, Université Versailles St-Quentin; CNRS/INSU, UMR 8190, Paris, France
4Department of Civil and Environmental Engineering, Massachusetts Institute of Technology, Cambridge, MA, USA
5Laboratoire de Météorologie Dynamique, IPSL, CNRS, UMR8539, 91128 Palaiseau CEDEX, France
6ECMWF, Reading, UK
7Royal Netherlands Meteorological Institute (KNMI), De Bilt, the Netherlands
8Program in Atmospheric and Oceanic Sciences, Princeton University and Geophysical Fluid Dynamics Laboratory/National Oceanic and Atmospheric Administration, Princeton, NJ, USA
9NASA Goddard Space Flight Center, Greenbelt, MD, USA
10Swedish Meteorological and Hydrological Institute, 60176 Norrköping, Sweden
Received: 17 Jul 2014 – Published in Atmos. Chem. Phys. Discuss.: 24 Sep 2014
Abstract. We have evaluated tropospheric ozone enhancement in air dominated by biomass burning emissions at high latitudes (> 50° N) in July 2008, using 10 global chemical transport model simulations from the POLMIP multi-model comparison exercise. In model air masses dominated by fire emissions, ΔO3/ΔCO values ranged between 0.039 and 0.196 ppbv ppbv−1 (mean: 0.113 ppbv ppbv−1) in freshly fire-influenced air, and between 0.140 and 0.261 ppbv ppbv−1 (mean: 0.193 ppbv) in more aged fire-influenced air. These values are in broad agreement with the range of observational estimates from the literature. Model ΔPAN/ΔCO enhancement ratios show distinct groupings according to the meteorological data used to drive the models. ECMWF-forced models produce larger ΔPAN/ΔCO values (4.47 to 7.00 pptv ppbv−1) than GEOS5-forced models (1.87 to 3.28 pptv ppbv−1), which we show is likely linked to differences in efficiency of vertical transport during poleward export from mid-latitude source regions. Simulations of a large plume of biomass burning and anthropogenic emissions exported from towards the Arctic using a Lagrangian chemical transport model show that 4-day net ozone change in the plume is sensitive to differences in plume chemical composition and plume vertical position among the POLMIP models. In particular, Arctic ozone evolution in the plume is highly sensitive to initial concentrations of PAN, as well as oxygenated VOCs (acetone, acetaldehyde), due to their role in producing the peroxyacetyl radical PAN precursor. Vertical displacement is also important due to its effects on the stability of PAN, and subsequent effect on NOx abundance. In plumes where net ozone production is limited, we find that the lifetime of ozone in the plume is sensitive to hydrogen peroxide loading, due to the production of HOx from peroxide photolysis, and the key role of HO2 + O3 in controlling ozone loss. Overall, our results suggest that emissions from biomass burning lead to large-scale photochemical enhancement in high-latitude tropospheric ozone during summer.
Revised: 29 Apr 2015 – Accepted: 04 May 2015 – Published: 03 Jun 2015
Arnold, S. R., Emmons, L. K., Monks, S. A., Law, K. S., Ridley, D. A., Turquety, S., Tilmes, S., Thomas, J. L., Bouarar, I., Flemming, J., Huijnen, V., Mao, J., Duncan, B. N., Steenrod, S., Yoshida, Y., Langner, J., and Long, Y.: Biomass burning influence on high-latitude tropospheric ozone and reactive nitrogen in summer 2008: a multi-model analysis based on POLMIP simulations, Atmos. Chem. Phys., 15, 6047-6068, doi:10.5194/acp-15-6047-2015, 2015.