A11C-0084
Characterizing Variability in the Spatial Distribution of Bromine Explosion Events in the Vicinity of Barrow, Alaska
Monday, 14 December 2015
Poster Hall (Moscone South)
Peter Peterson1, Kerri Pratt2, William R Simpson3, Paul B Shepson4, Denis Pöhler5, Udo Friess6, Johannes Zielcke7, Ulrich Platt6, Son V Nghiem8 and Holger Sihler9, (1)University of Michigan Ann Arbor, Ann Arbor, MI, United States, (2)University of Michigan Ann Arbor, Department of Chemistry and Department of Earth & Environmental Sciences, Ann Arbor, MI, United States, (3)University of Alaska Fairbanks, Fairbanks, AK, United States, (4)Purdue University, West Lafayette, IN, United States, (5)University of Heidelberg, Institute for Environmental Physics, Heidelberg, Germany, (6)University of Heidelberg, Heidelberg, Germany, (7)Institute of Environmental Physics, Heidelberg, Germany, (8)Jet Propulsion Laboratory, California Institute of Technology, Pasadena, CA, United States, (9)Max Planck Institute for Chemistry, Mainz, Germany
Abstract:
Reactive halogens (e.g. Br, BrO) are produced photochemically during springtime in the Arctic. Some dramatic effects of these halogen species are known (e.g. ozone depletion, mercury deposition), but changes in atmospheric composition related to this halogen chemistry, particularly those related to increasing sea ice loss and the transformation of Arctic sea ice cover, are unknown. In March 2012, the Bromine, Ozone, Mercury EXperiment (BROMEX) provided an opportunity to enhance our understanding of the spatial and temporal variability of halogen chemistry in the vicinity of Barrow, Alaska. During BROMEX, we used Multiple Axis Differential Optical Absorption Spectroscopy (MAX-DOAS) to measure BrO lower tropospheric vertical column densities (LT-VCD) and near-surface mixing ratios at Barrow, as well as on land-fast ice 40 km north east of Barrow, and a drifting platform on seasonal sea ice west of Barrow. Concurrently, an aircraft equipped with the Heidelberg Airborne Imaging DOAS Instrument (HAIDI) collected airborne BrO data at altitudes up to 3 km. These measurements showed several instances of spatial gradients in BrO between measurement sites, as well as times when BrO was present up to 1km aloft. We explore explanations for these features using local and synoptic meteorology, back-trajectory modelling, MODIS and airborne imagery, as well as satellite-instrument-based maps of synoptic sea ice classes and tropospheric BrO.
