HR: 15:10h
AN: B43F-07    [Abstracts]
TI: DOC Transport to the Arctic Ocean: Improving Basin-Wide Annual Flux Estimates
AU: * Holmes, R M
EM: rmholmes@whrc.org
AF: Woods Hole Research Center, 149 Woods Hole Road, Falmouth, MA 02540, United States
AU: McClelland, J W
EM: jimm@utmsi.utexas.edu
AF: University of Texas, Marine Science Institute 750 Channel View Drive, Port Aransas, TX 78373, United States
AU: Raymon, P
EM: praymond@yale.edu
AF: Yale University, 205 Prospect St, New Haven, CT 06511, United States
AU: Repeta, D J
EM: drepeta@whoi.edu
AF: Woods Hole Oceanographic Institution, Watson Building, MS#51, Woods Hole, MA 02543, United States
AU: Peterson, B J
EM: peterson@mbl.edu
AF: Marine Biological Laboratory, 7 MBL Street, Woods Hole, MA 02543, United States
AB: River fluxes connecting land to ocean integrate processes and changes occurring on land and impact the chemistry, physics, and biology of the receiving marine systems. One of the more important constituents in river water is dissolved organic carbon, particularly in the Arctic where continued warming and permafrost thaw is expected to have substantial implications for DOC fluxes in coming decades. Accurate assessment of current DOC flux to the Arctic Ocean is essential for detecting widespread changes in the future, and several recent basin-wide flux estimates have been published. In spite of this, it is argued that considerable uncertainty remains, primarily because of inadequate assessment of DOC fluxes during the critical spring breakup period (which can be extremely difficult to adequately sample) and limited sampling of the relatively "small" rivers (less than 100 km3/y discharge) which account for about half of the riverine freshwater inputs to the Arctic Ocean. Here we report new annual DOC flux estimates for Siberia's Lena and Ob' rivers (with annual discharges of about 530 and 400 km3, respectively) which incorporate data from high frequency sampling from the May-June 2007 high flow period as well as new DOC flux estimates for the three largest rivers on Alaska's North Slope. We then consider how these new data impact total estimated annual DOC flux to the Arctic Ocean and discuss next steps for further constraining basin-wide DOC flux estimates.
DE: 0414 Biogeochemical cycles, processes, and modeling (0412, 0793, 1615, 4805, 4912)
DE: 0428 Carbon cycling (4806)
DE: 0744 Rivers (0483, 1856)
SC: Biogeosciences [B]
MN: 2007 Fall Meeting