Articles | Volume 12, issue 3
Atmos. Chem. Phys., 12, 1255–1285, 2012

Special issue: POLARCAT (Polar Study using Aircraft, Remote Sensing, Surface...

Atmos. Chem. Phys., 12, 1255–1285, 2012

Research article 01 Feb 2012

Research article | 01 Feb 2012

Analysis of satellite-derived Arctic tropospheric BrO columns in conjunction with aircraft measurements during ARCTAS and ARCPAC

S. Choi1, Y. Wang1, R. J. Salawitch2, T. Canty2, J. Joiner3, T. Zeng1, T. P. Kurosu4,*, K. Chance4, A. Richter5, L. G. Huey1, J. Liao1, J. A. Neuman6,7, J. B. Nowak6,7, J. E. Dibb8, A. J. Weinheimer9, G. Diskin10, T. B. Ryerson7, A. da Silva3, J. Curry1, D. Kinnison9, S. Tilmes9, and P. F. Levelt11,12 S. Choi et al.
  • 1Georgia Institue of Technology, Atlanta, GA, USA
  • 2University of Maryland College Park, College Park, MD, USA
  • 3NASA Goddard Space Flight Center, Greenbelt, MD, USA
  • 4Harvard-Smithsonian Center for Astrophysics, Cambridge, MA, USA
  • 5Institute of Environmental Physics, University of Bremen, Bremen, Germany
  • 6Cooperative Institute for Research in Environmental Sciences (CIRES), University of Colorado Boulder, Boulder, CO, USA
  • 7NOAA Earth System Research Laboratory, Boulder, CO, USA
  • 8University of New Hampshire, Durham, NH, USA
  • 9National Center for Atmospheric Research, Boulder, CO, USA
  • 10NASA Langley Research Center, Hampton, VA, USA
  • 11Royal Netherlands Meteorological Institute (KNMI), De Bilt, The Netherlands
  • 12University of Technology Eindhoven, Eindhoven, The Netherlands
  • *now at: NASA Jet Propulsion Laboratory, Pasadena, CA, USA

Abstract. We derive tropospheric column BrO during the ARCTAS and ARCPAC field campaigns in spring 2008 using retrievals of total column BrO from the satellite UV nadir sensors OMI and GOME-2 using a radiative transfer model and stratospheric column BrO from a photochemical simulation. We conduct a comprehensive comparison of satellite-derived tropospheric BrO column to aircraft in-situ observations of BrO and related species. The aircraft profiles reveal that tropospheric BrO, when present during April 2008, was distributed over a broad range of altitudes rather than being confined to the planetary boundary layer (PBL). Perturbations to the total column resulting from tropospheric BrO are the same magnitude as perturbations due to longitudinal variations in the stratospheric component, so proper accounting of the stratospheric signal is essential for accurate determination of satellite-derived tropospheric BrO. We find reasonably good agreement between satellite-derived tropospheric BrO and columns found using aircraft in-situ BrO profiles, particularly when satellite radiances were obtained over bright surfaces (albedo >0.7), for solar zenith angle <80° and clear sky conditions. The rapid activation of BrO due to surface processes (the bromine explosion) is apparent in both the OMI and GOME-2 based tropospheric columns. The wide orbital swath of OMI allows examination of the evolution of tropospheric BrO on about hourly time intervals near the pole. Low surface pressure, strong wind, and high PBL height are associated with an observed BrO activation event, supporting the notion of bromine activation by high winds over snow.

Final-revised paper