Collaborator:
Paul Robbins
Transport and Storage of Carbon in the Pacific Ocean: Estimates from Inverse Models
NOAA/DOE OACES, 36 months
PROJECT SUMMARY
The focus of this proposal is estimating advective carbon fluxes and
flux divergences in the Pacific Ocean using data from the recent
WOCE/JGOFS one-time hydrographic survey. The NOAA Climate and Global
Change Program has made a substantial investment in collecting this
remarkable data set, with PIs here in the lead role of collecting a large
fraction of these data. It is time to capitalize on this investment
and use these data to further our understanding of the ocean in climate.
The effort will be a done in conjunction with and benefit from ongoing
work including (1) a synthesis of the WOCE observations in the Pacific
Ocean aimed at estimating the general circulation there (Johnson, PMEL;
Robbins and Talley, SIO; Toole, WHOI; Wijffels, CSIRO) and (2) quantification
of anthropogenic carbon storage in the ocean (Feely and Bullister, PMEL;
Wanninkhof and Peng, AOML; Sabine and Key, Princeton; Millero, U. Miami).
Linking these two projects will improve our knowledge of carbon fluxes
and storage within the Pacific Basin. Determinations of interior
ocean fluxes throughout the world ocean is a key effort inreducing uncertainty
in the global carbon budget. Analysis of surface PCO2
data and model output suggests that as well as storing carbon, the oceans
play a significant role in redistributing carbon between ocean basins and
from sink to source regions. However, the surface flux estimates
are hampered by sampling requirements and poorly known gas exchange coefficients.
Model output is biased by unresolved physics. The interior ocean
flux estimates made under this proposal will provide an independent assessment
and constraint on the magnitude of the net air-sea carbon transfer, natural
and anthropogenic, as well as its geographic distribution. Additionally
they will serve as a comparison benchmark for model output. Finally,
quantifying the physical processes responsible for the transport and storage
of carbon within the ocean is the first step to making future assessments
of how possible shifts in ocean circulation may impact the uptake rate
of anthropogenic carbon by the ocean. Of course, calculating interior
ocean carbon fluxes requires not only transoceanic sections of carbon data,
but the best possible estimate of the velocity field for each section as
well as the partition of natural and anthropogenic carbon. The proposed
work will capitalize on efforts currently underway to estimate the velocity
field in the Pacific basin and to estimate the anthropogenic carbon component
in that basin. A key component of this project will be the
construction of an error budget for the uncertainties of the estimates
of the total carbon flux and storage. A careful calculation of the
various errors in the calculations will contribute directly to the usefulness
of the estimates of the carbon fluxes and storage within the Pacific basin.
Moreover, additional benefits to more basic issues concerning the appropriate
methodology and allocation of resources for studying the oceanic carbon
cycle are anticipated.
Lynne Talley
Scripps Institution of Oceanography
University of California San Diego, M/C 0230
9500 Gilman Drive
San Diego, CA
tel: (619) 534-6610
fax: (619) 534-9820
ltalley@ucsd.edu
lynne@sam.ucsd.edu
Gregory C. Johnson
NOAA / PMEL / OCRD
7600 Sand Point Way NE, Bldg. 3
Seattle, WA 98115
tel: (206) 526-6806
fax: (206) 526-6744
gjohnson@pmel.noaa.gov
Richard A. Feely
NOAA/PMEL
7600 Sand Point Way NE
Seattle, WA 98115
tel : (206) 526-6214
fax : (206) 526-6744
feely@pmel.noaa.gov
Paul E. Robbins
Physical Oceanography Research Division
Scripps Institution of Oceanography
University of California, San Diego
9500 Gilman Drive, Mailcode 0230
La Jolla, CA 92093-0230
tel: (619) 534-6366
fax: (619) 534-9820
probbins@ucsd.edu