Southern Ocean export flux and air-sea O2 exchange: A synthesis of atmospheric O2/N2 measurements, satellite data and direct observations
Cynthia
D
Nevison, University of Colorado, Boulder, nevison@ucar.edu
(Presenting)
Matthew
A
Charette, Woods Hole Oceanographic Institution, mcharette@whoi.edu
Mati
Kahru, Scripps Institution of Oceanography, mati@spg.ucsd.edu
Ralph
F
Keeling, Scripps Institution of Oceanography, rkeeling@ucsd.edu
Kanchan
Maiti, Woods Hole Oceanographic Institution, kmaiti@whoi.edu
Brian
Gregory
Mitchell, Scripps Institution of Oceanography, gmitchell@ucsd.edu
Our project involves a synthesis of satellite-based ocean color and temperature, in situ ocean data, and atmospheric O2/N2 and N2O measurements to provide improved estimates of export flux and subsurface ventilation in the Southern Ocean. The satellite data will be incorporated into improved algorithms to generate time-series of ocean phytoplankton photosynthetic pigments, net primary production (NPP), and carbon export flux (f) ratios. The improved (f) ratios will be guided by analysis of a large new database of Th isotope and sediment trap measurements in the Southern Ocean. The export fluxes, calculated as the product of NPP * (f), will be combined with a simple mixed layer balance to estimate air-sea O2 fluxes, which will be used to force an atmospheric tracer transport model. The model results will be compared to atmospheric O2/N2 observations at southern hemisphere monitoring stations that have been corrected for thermal and terrestrial signals using standard methods as well as for biological O2 ventilation signals based on a new method involving atmospheric N2O. Simulations initially have focused on evaluating the ability of export flux algorithms to reproduce mean seasonal cycles in atmospheric O2/N2 and later will be extended to examine interannual variability.
NASA Carbon Cycle & Ecosystems Active Awards Represented by this Poster: