The Global Carbon Cycle
Postings [June 2000 - July 2005]
CCSP / USGCRP Carbon Cycle Working Group Members
For long term plans, see
of the Strategic Plan for the Climate
Change Science Program (2003) posted
on CCSP web site
Cycle Science Home Page
Carbon Cycle. Basic background information from NASA's Earth
Observatory Reference section.
Human Interactions with the Carbon
Cycle. Summary of a Workshop.
By Paul C. Stern for the National Research Council, Committee
on the Human Dimensions of Global Change, Division of Behavioral and
Social Sciences (Washington, DC: National Academy Press, 2002).
Increasing levels of atmospheric CO2 and methane are major drivers of climate change. The CCSP global carbon cycle element seeks to better quantify and understand the dynamics of the global carbon cycle that determine CO2 and methane fluxes and carbon storage in terrestrial and oceanic ecosystems. Carbon cycle processes depend on climate, thus linking carbon cycle and climate change analyses is critical. Carbon cycle research involves multiple disciplines and extends over a broad range of spatial and temporal scales. Major multi-agency activities include the North American Carbon Program (NACP), an effort to describe and reduce uncertainties about the North American carbon budget and underlying processes, and the Ocean Carbon and Climate Change (OCCC) Program, a research effort aimed at determining how climate change will affect the future behavior of the oceanic carbon sink. In FY 2009, NACP will address key gaps and uncertainties in the carbon syntheses developed previously, and aspects of the OCCC and NACP will be coordinated to better quantify and understand the roles of adjacent ocean basins in the North American carbon budget. NASA will launch the Orbiting Carbon Observatory (OCO) to provide, for the first time, consistent atmospheric carbon observations globally from space, and carbon data assimilation systems will begin to derive estimates of carbon sources and sinks from these measurements.
See the Carbon
Cycle Science Plan
For additional information on the Carbon Cycle Initiative, contact the Carbon Cycle Interagency Working Group's Program Office
Strategic Research Questions
What are the magnitudes and distributions of North American carbon
sources and sinks on seasonal to centennial time scales, and what are
the processes controlling their dynamics?
are the magnitudes and distributions of ocean carbon sources and sinks
on seasonal to centennial time scales, and what are the processes controlling
are the effects on carbon sources and sinks of past, present, and future
land-use change and resource management practices at local, regional,
and global scales?
do global terrestrial, oceanic, and atmospheric carbon sources and
sinks change on seasonal to centennial timescales, and how can this
knowledge be integrated to quantify and explain annual global carbon
will be the future atmospheric concentrations of carbon dioxide, methane,
and other carbon-containing greenhouse gases, and how will terrestrial
and marine carbon sources and sinks change in the future?
will the Earth system, and its different components, respond to various
options for managing carbon in the environment, and what scientific
information is needed for evaluating these options?
Plan for the U.S. Climate Change Science Program, Chapter
7, for detailed discussion of these research questions.
The U.S. Carbon Cycle Science Program is making progress in understanding the changes, magnitudes,
and distributions of carbon sources and sinks, the processes operating within and between major
terrestrial, oceanic, and atmospheric carbon reservoirs, and the underlying mechanisms involved,
including human activities, fossil fuel emissions, land use, and climate forcings. Program scientists
are currently quantifying many of the intricate complexities and interactions between the major carbon
reservoirs and climate. To execute this undertaking, Federal agencies and departments with carbon cycle
interests coordinate, manage, and support the overall science and implementation plans under two major
thrusts: North American Carbon Program (NACP) and Ocean Carbon and Climate Change (OCCC) Program. As
these science programs mature and generate needed carbon observations, field and experimental results
are being used to constrain advanced carbon models at scales from experimental sites to regions as an
important means of incorporating site, regional, and global observations into global carbon models and
analyses. The ultimate objective is to develop increasingly realistic and predictive coupled
carbon-climate and Earth system models to provide better insight into future feedbacks and drivers
between the major components of the Earth system.
U.S. CARBON CYCLE SCIENCE PROGRAM
The U.S. Carbon Cycle Science Program
contributes to all goals of the CCSP Strategic Plan (2003)—focusing particularly on Goal 2,
“Improved quantification of the forces bringing about changes in the Earth’s climate and
related systems.” The program addresses directly the six overarching carbon cycle questions of
Chapter 7 of the CCSP Strategic Plan. The research element is synergistic with the Ecosystems, Global
Water Cycle, Climate Variability and Change, Atmospheric Composition, Land-Use and Land-Cover Change,
and Human Contributions and Responses research elements. The agencies responsible for carbon cycle
research are DOE; NASA; NIST; NOAA; NSF; USDA’s Agricultural Research Service (ARS), Cooperative
State Research, Education, and Extension Service (CSREES), Forest Service, and Natural Resources
Conservation Service (NRCS); and USGS. Together, they have planned and are coordinating a
multidisciplinary research strategy to integrate the broad range of needed infrastructure and
resources, scientific expertise, and stakeholder input essential for program success and improved
In FY 2009, a new CCSPwide research priority will be initiated to quantify the magnitude and
dynamics of carbon cycling of high-latitude ecosystems under abrupt climate change. In support of this
research initiative, the U.S. Carbon Cycle Science Program will coordinate a concerted Federal effort
addressing high-latitude carbon cycle research (observations, attribution, prediction, and mitigation),
which will be conducted in unison with its priorities under the NACP and OCCC programs. To accomplish
the carbon cycle element of the new CCSP priority at high latitudes, the interagency working group will
solicit new investments and reprogram previous research investments to complement current research in
order to fill gaps, and promote and augment ongoing carbon observations and networks in high-latitude
lands and ocean ecosystems. The enhanced emphasis on high-latitude ecosystems will provide critical
scientific information on past and current carbon dynamics of undersampled regions of North America and
adjacent oceans, as well as other undersampled regions of the world, such as Antarctica and the
adjacent Southern Ocean.
THE NORTH AMERICAN CARBON PROGRAM
NACP is designed to address strategic
research question 7.1, and elements of questions 7.2 through 7.6, in Chapter 7 of the CCSP Strategic
Plan. For example, it will quantify the magnitudes and distributions of terrestrial, freshwater,
oceanic, and atmospheric carbon sources and sinks for North America and adjacent coastal oceans;
enhance understanding of the processes controlling source and sink dynamics; and produce consistent
analyses of North America’s carbon budget that explain regional and continental contributions and
year-toyear variability. This program is committed to reducing uncertainties related to the increase of
carbon dioxide and methane in the atmosphere and the amount of carbon, including the fraction of fossil
fuel carbon, being taken up by North America’s ecosystems and adjacent coastal oceans.
As research programs mature, scientific and governmental collaborations on carbon cycle science are
broadening and escalating with international neighbors within North America as well as with extended
Northern Hemisphere interests, international organizations, and global partners.
THE OCEAN CARBON AND CLIMATE CHANGE PROGRAM
OCCC is designed to address
strategic research question 7.2, and elements of questions 7.3 through 7.6, in Chapter 7 of the CCSP
Strategic Plan. For example, in regards to question 7.2, it will focus on oceanic research aimed at
quantifying how much atmospheric carbon dioxide is being taken up by the ocean at the present time and
how climate change will affect the future behavior of the oceanic carbon sink. The terrestrial and
ocean carbon programs are synergistic, integrating program activities addressing carbon dynamics on the
coastal shelves adjacent to North America (questions 7.1 and 7.2), where carbon changes in the
terrestrial system greatly influence carbon processes in the coastal ocean.