Carbon Dioxide Drawdown During Southern Ocean GasEx: A Preliminary Assessment of the Role of Phytoplankton
Robert
David
Vaillancourt, Lamont-Doherty Earth Observatory, vaillanc@ldeo.columbia.edu
(Presenting)
John
F
Marra, Brooklyn College, jfm7780@brooklyn.cuny.edu
Veronica
Lance, Lamont-Doherty Earth Observatory, vlance@ldeo.columbia.edu
Bruce
Robert
Hargreaves, Lehigh University, brh0@lehigh.edu
During the recent Southern Ocean GasEx study (Feb 24-April 10, 2008) aboard the R/V Ron H. Brown, we measured vertical profiles of C-14 uptake in the euphotic zone. We will present preliminary results on photosynthesis-Irradiance (PE) experiments conducted on seawater captured from 8 depths from the surface to 100 meters. Repeated PE profiles over a several week period within an SF6-tagged water mass will allow us to estimate the size of the CO2 sink afforded by primary production, and diel PE will allow us to determine the daily fluctuations in CO2 dynamics that are biologically-mediated. Lastly, we will present preliminary data testing the hypothesis that near-surface primary productivity (based on primary productivity modeled from PE kinetics parameters) can be predicted based on light absorption by phytoplankton pigments.
NASA Carbon Cycle & Ecosystems Active Awards Represented by this Poster: