HR: 0800h
AN: B51C-0611    [Abstracts]
TI: Modeling transport, fate, and lifetime of riverine DOC in the Arctic Ocean
AU: * Manizza, M
EM: mmanizza@ocean.mit.edu
AF: Department of Earth, atmospheric and Planetary Sciences, Massachusetts Institute of Technology, 77, Massachusetts Avenue, Cambridge, MA 02139, United States
AU: Follows, M J
EM: mick@ocean.mit.edu
AF: Department of Earth, atmospheric and Planetary Sciences, Massachusetts Institute of Technology, 77, Massachusetts Avenue, Cambridge, MA 02139, United States
AU: Dutkiewicz, S
EM: stephd@ocean.mit.edu
AF: Department of Earth, atmospheric and Planetary Sciences, Massachusetts Institute of Technology, 77, Massachusetts Avenue, Cambridge, MA 02139, United States
AU: Hill, C N
EM: cnh@mit.edu
AF: Department of Earth, atmospheric and Planetary Sciences, Massachusetts Institute of Technology, 77, Massachusetts Avenue, Cambridge, MA 02139, United States
AU: Menemenlis, D
EM: menemenlis@jpl.nasa.gov
AF: Jet Propulsion Laboratory, California Institute of Technology, 4800 Oak Grove Drive, Pasadena, CA 91109-8099, United States
AU: McClelland, J W
EM: jimm@mail.utexas.edu
AF: Intitute of Marine Science, University of Texas at Austin, 750 Channel View Drive, Port Aransas, TX 78373-5015, United States
AU: Peterson, B J
EM: peterson@mbl.edu
AF: Marine Biological Laboratory, 7 MBL Street, Woods Hole, MA 02543, United States
AB: We use a numerical model to examine the fate of riverine fluxes of dissolved organic carbon (DOC) in the Arctic basin. The model is based on the Arctic sector of an eddy-permitting ocean model (MITgcm), where the spherical domain is projected onto a cube to avoid polar a singularity in the Arctic region. The physical model is forced by time-varying NCEP re-analysis products and an explicit representation of fresh water run-off in the Arctic region. Passive tracers and idealized "DOC" tracers are explicitly represented, transported by the prognostic circulation fields. The tracers have sources near the mouths of major Arctic river systems, distributed in space and time according to observational estimates of regional DOC discharge. The DOC-like tracers have a finite, tunable lifetime in the water column. Comparison of a suite of model sensitivity studies with observed tracer relationships from the region suggest that the model captures the main circulation features and source distributions appropriately. Tracer relationships in the model match those observed most closely when the lifetime of riverine source DOC is about 1 year. We will discuss the role of the riverine DOC sources in regulating regional air-sea carbon fluxes in the context of a more complete biogeochemical model.
DE: 4207 Arctic and Antarctic oceanography (9310, 9315)
DE: 4512 Currents
DE: 4805 Biogeochemical cycles, processes, and modeling (0412, 0414, 0793, 1615, 4912)
DE: 4806 Carbon cycling (0428)
SC: Biogeosciences [B]
MN: 2007 Fall Meeting