HR: 1340h
AN: B33A-0247    [Abstracts]
TI: Dust Deposition, Ecosystem Response, and Oceanic Uptake of Atmospheric CO2
AU: * Moore, J K
EM: jkmoore@uci.edu
AF: University of California, Irvine, Dept. of Earth System Science Croul Hall, Irvine, CA 92697-3100 United States
AU: Doney, S C
EM: sdoney@whoi.edu
AF: Woods Hole Oceanographic Institution, Dept. of Marine Chem. and Geochem. MS #25, Woods Hole, MA 02543-1543 United States
AB: The transport of mineral dust from the continents to the oceans accounts for most inputs of the important micronutrient iron to surface waters. Increasing dust deposition can lead to increased biological production and export, directly, in the iron-limited High Nitrate, Low Chlorophyll (HNLC) regions, and indirectly by increasing rates of nitrogen fixation in tropical and subtropical regions where the community is often limited by nitrogen availability. Similarly, reductions in dust deposition can lead to reduced biological productivity through both of these pathways. Our global-scale, Biogeochemistry/Ecosystem/Circulation (BEC) model includes explicit representation of both pathways whereby dust deposition can influence ocean biogeochemical cycling. The BEC model includes explicit iron cycling and multiple phytoplankton functional groups, including the nitrogen fixers. We examine the ecosystem response to variations in dust deposition over interannual to decadal timescales. The BEC model will be used to quantify the shifts in phytoplankton production and community structure, global-scale patterns in nutrient limitation of phytoplankton growth rates, and surface ocean biogeochemical cycling. The sensitivity of air-sea carbon dioxide exchange over interannual to decadal timescales to variations in dust deposition will also be examined.
UR: http://www.ess.uci.edu/~jkmoore.html
DE: 4806 Carbon cycling
DE: 4842 Modeling
DE: 4845 Nutrients and nutrient cycling
DE: 1615 Biogeochemical processes (4805)
SC: Biogeosciences [B]
MN: 2004 AGU Fall Meeting