HR: 16:15h
AN: OS24B-02    [Abstracts]
TI: CLIVAR/CO2 Repeat Hydrography Program: Initial Carbon Results from the North Pacific Ocean
AU: * Feely, R A
EM: Richard.A.Feely@noaa.gov
AF: NOAA Pacific Marine Environmental Laboratory, 7600 sand Point Way NE, Seattle, WA 98115-6349 United States
AU: Sabine, C L
EM: Chris.Sabine@noaa.gov
AF: NOAA Pacific Marine Environmental Laboratory, 7600 sand Point Way NE, Seattle, WA 98115-6349 United States
AU: Ono, T
EM: tono@fra.affrc.go.jp
AF: Hokkaido National Fisheries Research Institute, 116 Katsurakoi, Kushiro, JPN 085-0802
AU: Murata, A
EM: akihiko.murata@jamstec.go.jp
AF: Japan Rarine Science and Technology Center, 2-15 Natsushimi-cho Yokosuka, Kanagawa, 237-0061 Japan
AU: Key, R
EM: Key@Princeton.edu
AF: Princeton University, Princeton New Jersey, Princeton, NJ 08533 United States
AU: Winn, C
EM: cwinn@hpu.edu
AF: Hawaii Pacific University, 1164 Bishop Street, Honolulu, HA 96813 United States
AU: Lamb, M F
EM: Marilyn.F.Roberts@noaa.gov
AF: NOAA Pacific Marine Environmental Laboratory, 7600 sand Point Way NE, Seattle, WA 98115-6349 United States
AU: Greeley, D
EM: Dana.Greeley@noaa.gov
AF: NOAA Pacific Marine Environmental Laboratory, 7600 sand Point Way NE, Seattle, WA 98115-6349 United States
AB: The primary goal of the CLIVAR/CO$_2$ Repeat Hydrography Program is to quantify the role of the ocean in sequestering anthropogenic CO$_2$. Information on shorter timescales is essential to determine any feedbacks of oceanic carbon system due to climate change, and to determine the impacts of natural variability. The North Pacific Ocean plays a unique role in controlling the long-term fate of anthropogenic CO$_2$ because: (1) the North Pacific is the final destination of circulation of the deep water that contains a high level of preformed nutrients and dissolved inorganic carbon (DIC); and (2) the North Pacific Intermediate Water stores dissolved CO$_2$ for more than a few tens of years. Discrete high-quality dissolved inorganic carbon and total alkalinity data were acquired as part of the WOCE/JGOFS Global CO$_2$ survey in the Pacific Ocean between 1991 and 1999 followed by repeat surveys in 2001 and 2004 as part of the Sub-arctic Gyre Experiment (SAGE) along the P17N line in the eastern North Pacific and the CLIVAR/CO$_2$ Repeat Hydrography Program east-west P2 cruise along 30$^\circ$N. The DIC increases range from 5--35 $\mu$mol kg$^{-1}$ at intermediate depths from about 100--800~m depth along the 30$^\circ$N section reflect the rapid uptake, transport, and transformation of CO$_2$ in these waters. The DIC changes are consistent with the corresponding changes in AOU and other water mass properties, suggesting that decadal changes in the local circulation, invasion of anthropogenic CO$_2$ into the interior North Pacific, and/or changes in new production and remineralization of organic matter along the flow path are all possible causes for the observed variations. The results of these research studies suggest an annual CO$_2$ uptake of 1.0--1.4 $\mu$mol kg$^{-1}$ yr$^{-1}$ in the mixed layer, based on direct observations and multiple linear regression approaches. Water column integrated uptake rates ranged from 0.25 to 1.3 mol m$^{-2}$ yr$^{-1}$, depending on location and/or approach used. Deep ventilation within the Kuroshio Extension and the subsequent circulation in the subtropical gyre generates a strong east-west gradient in the anthropogenic CO$_2$ penetration depth. The combined effect of the tilted density surfaces and the younger waters with higher anthropogenic CO$_2$ concentrations leads to higher total column inventories in the western North Pacific. The integrated amount of anthropogenic CO$_2$ in the North Pacific is estimated to be 16.5 Pg C through 1994 north of the equator but not including the marginal seas. This estimate is approximately 16% of the amount of anthropogenic CO$_2$ taken by the global oceans.
UR: http://www.pmel.noaa.gov/co2/co2-home.html
DE: 4805 Biogeochemical cycles (1615)
DE: 4806 Carbon cycling
DE: 4808 Chemical tracers
DE: 4835 Inorganic marine chemistry
DE: 4532 General circulation
SC: Ocean Sciences [OS]
MN: 2004 AGU Fall Meeting