Oceanic distributions and emissions of short-lived halocarbons Academic Article uri icon

abstract

  • Using data from seven cruises over a 10year span, we report marine boundary layer mixing ratios (i.e., dry mole fractions as pmol mol1 or ppt), degrees of surface seawater saturation, and airsea fluxes of three shortlived halocarbons that are significant in tropospheric and potentially stratospheric chemistry. CHBr3, CH2Br2, and CH3I were all highly supersaturated almost everywhere, all the time. Highest saturations of the two polybrominated gases were observed in coastal waters and areas of upwelling, such as those near the equator and along ocean fronts. CH3I distributions reflected the different chemistry and cycling of this gas in both the water and the atmosphere. Seasonal variations in fluxes were apparent where cruises overlapped and were consistent among oceans. Undersaturations of these gases were noted at some locations in the Southern Ocean, owing to mixing of surface and subsurface waters, not necessarily biological or chemical sinks. The Pacific Ocean appears to be a much stronger source of CHBr3 to the marine boundary layer than the Atlantic. The high supersaturations, fluxes, and marine boundary layer mixing ratios in the tropics are consistent with the suggestion that tropical convection could deliver some portion of these gases and their breakdown products to the upper troposphere and lower stratosphere.

published proceedings

  • GLOBAL BIOGEOCHEMICAL CYCLES

altmetric score

  • 3

author list (cited authors)

  • Butler, J. H., King, D. B., Lobert, J. M., Montzka, S. A., Yvon-Lewis, S. A., Hall, B. D., ... Elkins, J. W.

citation count

  • 183

complete list of authors

  • Butler, James H||King, Daniel B||Lobert, Juergen M||Montzka, Stephen A||Yvon-Lewis, Shari A||Hall, Bradley D||Warwick, Nicola J||Mondeel, Debra J||Aydin, Murat||Elkins, James W

publication date

  • March 2007