Air-Sea Gas Exchange Parameterizations from a Noble Gas Time-Series
Collaborators:
Dr. William Jenkins (WHOI)
Dr. Scott Doney (WHOI)
Dempsey E. Lott, III (WHOI)
Air-sea gas exchange, the flux of a gas across the ocean-water interface,
is a major part of the biogeochemical cycle of many climatically important
gases, such as CO2, N2O, DMS and O2. Air-sea
gas exchange is very difficult to measure directly and thus parameterizations
are commonly used that allow researches to calculate the bulk flux of a gas
from some relatively easy to measure variables such as the wind speed. These
parameterizations are used in all climate models as well as in many data-based
studies. For example, in order to use a gas as a tracer, one must calculate the
air-sea gas exchange flux of a gas. The importance of such parameterizations is
underscored by the fact that the most widely used of the existing
parameterizations, Wanninkhof (1992), has been cited 1000 times. Nonetheless, existing parameterizations,
including Wanninkhof (1992) have several significant shortcomings, perhaps most
notably having an uncertainty of 25 to 50%. We are using the noble gas time-series in
conjunction with one-dimensional numerical modeling (Stanley et al, 2006) in
order to develop a new parameterization that has uncertainties of only 10%,
that explicitly includes bubble processes, and that is based on monthly to
seasonal time-scales, the time-scale that matches that of the biogeochemical
cycles of many gases (Stanley et al, submitted).
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