HR: 1340h
AN: A43C-0067    [Abstracts]
TI: Fluxes of Short-Lived Organic Halogens Into the Marine Boundary Layer
AU: * King, D B
EM: daniel.king@drexel.edu
AF: Chemistry Department, Drexel University, Phildelphia, PA 19104 United States
AU: Butler, J H
EM: james.h.butler@noaa.gov
AF: NOAA Climate Monitoring and Diagnostics Laboratory, 325 Broadway, Boulder, CO 80305 United States
AU: Yvon-Lewis, S A
EM: Shari.Yvon-Lewis@noaa.gov
AF: NOAA Atlantic Oceanographic and Meteorological Laboratory, 4301 Rickenbacker Cswy, Miami, FL 33149 United States
AU: Mondeel, D J
EM: debra.j.mondeel@noaa.gov
AF: Cooperative Institute for Research in Environmental Sciences, University of Colorado, Boulder, CO 80309 United States
AU: Hall, B D
EM: bradley.hall@noaa.gov
AF: NOAA Climate Monitoring and Diagnostics Laboratory, 325 Broadway, Boulder, CO 80305 United States
AB: Recent interest in the contribution of short-lived halogenated gases to stratospheric ozone depletion prompted us to evaluate the fluxes of these gases from the ocean surface into the atmosphere in areas of potentially high convection. We make our evaluation based upon two cruises in the Pacific Ocean, one running from Kwajalein (10 N) to Hawaii (21 N) to Alaska (54 N) to Seattle (48 N) during the fall of 1999 and the other from Guam (12 N ) to Hawaii (21 N ) to Newport, Oregon (44 N), during the spring and early summer of 2004. Although the two cruises do not overlap exactly, they course through similar water masses during nearly opposite seasons. This allows us to make seasonal comparisons of the saturations of these gases and, by extension, evaluate their fluxes relative to their potential to be associated with deep convection. In the Tropical West Pacific, where the potential for convection is highest, spring and summer supersaturations of the very short-lived gases (CH3I, CH2Br2, and CHBr3) were about twice those in the fall, ranging from a mean of 25% for CH2Br2 during the fall to 4300% for CH3I during the spring/summer. In the temperate Northeast Pacific, these gases remained supersaturated at all times, but at lower levels than in the tropics. Their supersaturations during the spring and summer also were about twice those of those in the fall, ranging from 40% for CH2Br2 to 3200% for CH3I. CH3Br, a slightly longer lived gas, behaved differently, remaining undersaturated at around -30% in tropical waters and swinging from a mean of -20% in the fall to +20% in the summer in temperate waters, consistent with seasonality previously observed for this gas in temperate waters.
DE: 4805 Biogeochemical cycles (1615)
DE: 4820 Gases
DE: 0312 Air/sea constituent fluxes (3339, 4504)
DE: 0365 Troposphere--composition and chemistry
SC: Atmospheric Sciences [A]
MN: 2004 AGU Fall Meeting