PROGRAM TITLE:	Ocean-Atmosphere Carbon Fluxes (JGOFS)
ACTIVITY STREAM: 	Process Research
SCIENCE ELEMENT:	Biogeochemical Dynamics

DESCRIPTION:  Since the Industrial Revolution, the concentrations of 
atmospheric CO2, a major greenhouse gas, have been increasing.  The 
increase of CO2 in the atmosphere, largely due to fossil fuel combustion, is 
predicted to have profound consequences for our future climate.  However, 
while various model-based scenarios of the Earth's response to this increase 
have been constructed, the validity of these models is highly sensitive to the 
uncertainties in quantitative global estimates of the sources and sinks of CO2 
and the processes which regulate them.

As articulated in the 1990 IPCC Scientific Assessment of Climate Change, 
oceanic uptake of atmospheric CO2 is estimated to be 2 gigatons (1015 grams) 
per year, 37% of the anthropogenic CO2 derived from fossil fuel combustion 
(5.4 gigatons per year).  Unfortunately, the oceanic uptake term is highly 
uncertain, since it is based on the difference between measurements of CO2 
accumulated in the atmosphere (3.4 gigatons per year) and historical records 
of fossil fuel combustion; that is, our uncertainty with regard to the fate of 
anthropogenic CO2 results from a lack of direct measurements of changes in 
the carbon content of the biosphere and the ocean.  Producing reliable 
predictions of future climate scenarios requires a quantitative understanding 
of the ocean's response to the CO2 increases. 

The goal of the Ocean-Atmosphere Carbon Fluxes project is to provide a 
predictive understanding, through observations and modeling, of the role of 
the ocean in sequestering the increasing burden of atmospheric CO2.  This 
program encompasses NOAA's primary contribution to the Joint Global 
Ocean Flux Study (JGOFS) of the of the International Geosphere Biosphere 
Program (IGBP).  The principle thrusts of the Ocean-Atmosphere Carbon 
Fluxes project are:

--	carbon system measurements on deep ocean survey cruises to better 
understand the  variability of carbon storage between the surface and deep 
ocean on decadal timescales,
--	time-series measurements of atmospheric CO2 and carbon-13 through 
NOAA's global cooperative flask sampling network, and
--	oceanic and atmospheric general circulation modeling to examine 
uptake of CO2 by the ocean and terrestrial biosphere.

STAKEHOLDERS:  This project has strong linkages to JGOFS.  It also supports 
the International Global Atmospheric Chemistry (IGAC) program of IGBP.  
The IGAC program includes global measurements and modeling of 
atmospheric CO2 and it's isotopic composition.  Measurements made along 
meridional ocean sections and process study cruises supported by this project 
will be a useful "ground-truthing" component of the NASA SeaWIFS Ocean 
Color Satellite mission.  The Ocean-Atmosphere Carbon Fluxes project also 
has strong ties to DOE's Carbon Dioxide Research Program, which supports 
CO2 measurements on WOCE cruises.  Additionally, DOE is providing 
certified seawater reference materials to NOAA and other 
government/academic investigators to ensure analytical measurement 
quality control and performance monitoring of coulometers used to measure 
total CO2 in seawater samples collected on U.S. and international research 

SHORT-TERM POLICY PAYOFFS:  The degree to which models can 
accurately predict future climate scenarios (e.g., greenhouse warming) is 
intimately coupled to the quality and quantity of environmental data.  There 
are presently vast regions of the ocean for which carbon system data are 
lacking.  This project will help provide carbon system measurements in these 
regions so that reliable predictions of future climate be made.

PROGRAM CONTACT:  James F. Todd, Office of Global Programs, 1100 
Wayne Avenue, Suite 1225, Silver Spring, MD 20910 (301) 427-2089 X32.