An improved oceanic budget for methyl chloride Academic Article uri icon


  • [1] We present results that improve the estimates of the global net sea-to-air flux, global oceanic emission, global oceanic uptake, and partial atmospheric lifetime of methyl chloride (CH3Cl) with respect to oceanic loss. This study includes improved parameterizations for solubility and saturation anomaly-sea surface temperature relationships for CH3Cl, along with the use of an updated gas transfer velocity from a recent study. By measuring solubilities of CH3Cl in pure water and seawater over a temperature range from 0C to 40 C, we obtained a new solubility function with both temperature and salinity dependencies. We also developed a new parameterization of seasonal CH3Cl saturation anomaly (%) as a function of both sea surface temperature and wind speed using data from 10 different cruises with an extensive coverage in the global surface ocean. Using the new solubility function and the new seasonal %-(SST, wind speed) relationships, we estimated the global net sea-to-air flux of CH3Cl at 335 (210 to 480) Ggyr-1. For the first time, the global flux of CH3Cl was broken into a unidirectional gross emission and a unidirectional gross uptake, which were estimated at 700 (510 to 910) Ggyr -1 and -370 (-430 to -300) Ggyr-1. The partial atmospheric lifetime of CH3Cl with respect to the oceanic uptake was revised to 12 (10-15) years, resulting in a revision on the atmospheric lifetime of CH 3Cl from the previous estimate of 1.0 year to 1.2 years. 2012 American Geophysical Union. All Rights Reserved.

published proceedings


altmetric score

  • 3.25

author list (cited authors)

  • Hu, L., Yvon-Lewis, S. A., Butler, J. H., Lobert, J. M., & King, D. B.

citation count

  • 22

complete list of authors

  • Hu, Lei||Yvon-Lewis, Shari A||Butler, James H||Lobert, Juergen M||King, Daniel B

publication date

  • February 2013