U'S' Climate Change Research Program

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U.S. Climate Change Research Program
Program Element Interactions and Linkages

• Carbon Cycle
• Ecosystems
• Land Use and Land Cover Change

William Hohenstein, Department of Agriculture,
Moderator Bill Emanuel, University of
Virginia Steve Wofsy, Harvard University Richard
Houghton, Woods Hole Research Center Daniel
Lashof, Natural Resources Defense Council Cynthia
Rosenzweig, NASA-Goddard Institute for Space
Studies Jeff Amthor, Department of Energy,
Rapporteur Allen Solomon, Environmental
Protection Agency, Rapporteur
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Carbon CycleEcosystemsLand-Use and Land Cover
Change

• Linkages between carbon cycle, ecosystem, and
  land use and land cover change sections of the
  plan.
• Comments by invited reviewers.
• Opportunities for questions, comments, and
  discussion from workshop participants.

Submit comments electronically according to
instructions under Strategic Plan
on http//www.climatescience.gov/
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U.S. Climate Change Research Program
Program Element Interactions and Linkages

• Carbon Cycle
• Ecosystems
• Land Use and Land Cover Change

Bill Emanuel University of Virginia
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Future greenhouse gas concentrations?
Broad carbon cycle questions require
consideration of land use, land cover, and
ecosystems

• What will be the future atmospheric CO2 and CH4
  concentrations?
• How will terrestrial and marine carbon sources
  and sinks change in the future?

The carbon cycle science program will collaborate
with all CCRP research elements to assemble,
merge, and analyze carbon, biogeochemical,
physical, and socioeconomic information for
comprehensive reporting on the state of the
global carbon cycle.
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Carbon cycle research premises

• Elevated atmospheric CO2 concentrations,
  additions of nutrients, and changes in land
  management practices can significantly enhance or
  reduce ecological carbon sinks.
• Northern Hemisphere terrestrial sink ? 1.8 ? 1015
  gC/year
• Recovering forests
• Fire management
• Increasing CO2, N deposition, and climatic change
• Better understanding and analysis capabilities
  are prerequisites for planning, implementing, and
  monitoring North American carbon sequestration.

The carbon cycle section of the plan acknowledges
an urgent need for improved understanding of the
processes of land-use change and the impacts of
environmental and resource management decisions.
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Carbon cycle research questions

• What are the magnitudes and distributions of
  North American and of global carbon sources and
  sinks, how are they changing, and what processes
  are controlling their dynamics?
• What are the effects of past, present, and future
  land-use change and resource management practices
  on carbon sources and sinks?
• How will the earth system respond to various
  options for managing carbon in the environment?

Central US extending to continental field
campaigns. Biomass and soil carbon inventories.
Networks of long-term experimental sites. Remote
sensing.
Field studies, experiments, modeling. Monitoring.
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Land use and land cover change research premises

• The combination of climate and land-use change
  may have profound effects on the habitability of
  the planet in more significant ways than either
  acting alone.
• While land-use change is often a driver of
  environmental and climatic changes, a changing
  climate can in turn affect land use and land
  cover.

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Land use and land cover change objectives
Initiatives linked to carbon cycling and
ecosystems include

• Investigate the primary drivers of land use and
  land cover change.
• Develop 1050 year projections of land use and
  land cover.
• U.S.
• Global
• Assess impacts on environmental, social, and
  economic systems and on human health.

Process models of land use and land cover
dynamics.
Mapping landscape attributes. Integrating remote
sensing and in situ data.
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Ecosystem carbon cycling objectives

• Determine linkages and feedbacks between
  ecosystems and global change.
• Altered ecosystem exchanges of greenhouse gases,
  aerosols, and volatile organic compounds.
• Changes in ecosystem surface albedo.
• Changes in the fraction of absorbed radiation
  used to evaporate water compared to direct
  heating of plants and soils.

Large-scale field experiments. Long-term
monitoring. Models incorporating remote sensing
data. Spatially explicit ecosystem models.