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World Ocean Circulation Experiment (WOCE)
The facility was initially established in 1989 for analysis
of radiocarbon in samples collected during the World Ocean
Circulation Experiment. Detailed
reports of these analyses including ancillary information
have been regularly reported by NOSAMS to the WOCE principal
14C investigators and to the WOCE Hydrographic
Office (WHP). These data are available electronically through
the WHP.
For references to publications and reports resulting from
this research including access to the original text of final
data reports for the various WOCE legs and copies of several
grey literature reports see the GLobal
Ocean Data Analysis Project web pages. The "Data
and Data Visualization Tools" provides access to graphics
as well as downloads of data compilations and mapped fields.
Under "Publications" the following two pubs are
the most useful descriptions of the work and can be directly
downloaded from the site:
Key, R.M., A. Kozyr, C.L. Sabine, K. Lee, R. Wanninkhof,
J. Bullister, R.A. Feely, F. Millero, C. Mordy, T.-H. Peng. 2004.
A global ocean carbon climatology: Results from GLODAP. Global
Biogeochemical Cycles, Vol. 18, GB4031.
Sabine, C. L., R. M. Key, A. Kozyr, R. A. Feely, R. Wanninkhof,
F. J. Millero, T.-H. Peng, J. L. Bullister, and K. Lee. 2005. Global
Ocean Data Analysis Project: Results and Data. ORNL/CDIAC-145, NDP-083.
Carbon Dioxide Information Analysis Center, Oak Ridge National
Laboratory, U.S. Department of Energy, Oak Ridge, Tennessee, 110 pp.
Climate Variability and Predictability
(CLIVAR)
In future years, the program on Climate Variability and Predictability
will continue surveys of the distribution of radiocarbon in
oceanic DIC. Dr. Ann McNichol, the NOSAMS staff chemist and
one of the co-PIs on this proposal, has submitted a proposal
to manage collection of samples and provision of radiocarbon
analyses to CLIVAR. This proposal was funded to provide approximately
3960 samples over a six-year period beginning in 2003.
Environmental Studies
Spills of oil and other industrial products derived from fossil
fuels can be studied using 14C. The carbon in
these products has been stored in crustal reservoirs for millions
of years. All of the 14C has decayed. When soils
and other natural media are analyzed, the presence of petroleum
derivatives is signaled by levels of 14C lower
than those encountered in unpolluted settings. A salt marsh
on Buzzard’s Bay, in West Falmouth, was fouled by an oil spill
in 1969. Since then, it has provided a laboratory for the
long-term study of such spills. Two recent
reports describe these investigations and the role of
radiocarbon studies.
In general, 14C serves as a “negative
label” for products derived from fossil sources. Tracing
experiments using conventional, positive labels can provide
spectacular sensitivity, but they require injection of isotopically
labeled materials in natural environments. Moreover, the
time clock for such experiments starts with the injection.
If slow, natural processes are to be studied, the experiment
must also be very long. Exploitation of the absence of 14C
as an inherent, natural tracer does not suffer from those
disadvantages. And, when analyses are tightly
focused – on single compounds, or classes of compounds, for
example – its sensitivity is more than adequate for the exploration
of important questions. At whoi, Timothy Eglinton, Chris Reddy, and
John Hayes are developing these techniques in a project entitled
“Molecular-Isotopic
Tools for Environmental Research,” funded by the National
Science Foundation’s Division of Chemistry.
Marine and Geochronologies
Paleoclimatic studies require accurate and precise time scales.
Ages less than 40,000 years are usually based on radiocarbon.
NOSAMS provides hundreds of AMS analayses of biologically
precipitated calcium carbonate as well as acid-insoluble organic
carbon (usually where calcareous fossils are unavailable)
for paleo studies each year.
Global Change Studies
With each report of AMS results, we ask that investigators
send us a list of publications in which they've utilized radiocarbon
results produced by our facility. The PDF-formatted document
linked below lists citations we have accumulated since the
inception of the facility and while not exhaustive, represents
the body of work from over 500 individual investigators who
have asked us to analyze more than 22,000 samples for a wide
variety of global change studies. In addition to these, more
than 15,000 seawater DIC samples have been analyzed as part
of the WOCE and CLIVAR programs.
» List of References
citing NOSAMS data 2002-2007 (pdf version).
» List of References
citing NOSAMS data prior to 2002(pdf version).
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