Land Use, the Carbon Cycle and Ecosystems

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Land Use, the Carbon Cycle and Ecosystems

• Comments on the Strategic Plan
• Daniel A. Lashof
• Science Director
• NRDC Climate Center

2
General Comments

• Recognize Existing Knowledge Base
• Establish an Organizing Framework
• Integrate Land Use, Carbon Cycle and Ecosystem
  Chapters
• Focus on Overriding Issues

3
Recognize Knowledge Base

• Expand State of Knowledge Sections
• Site Climate Action Report / National Assessment
• E.g., Some ecosystems such as alpine meadows are
  likely to disappear in some places
• Link to IPCC Assessment Process

4
Establish Organizing Framework

• Emission Budgets for Stabilization
• Vulnerabilities

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Carbon Budget Consumption
Ask not, How big is the pie? Ask, How much of
the pie is left?
SAR Budget for 450 ppm Stabilization SRES A1B
Emissions
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Integrate Chapters

• Reduce Redundancy
• Avoid Inconsistencies
• E.g. Carbon cycle models assuming CO2
  fertilization in forests that have been cleared
  for agriculture
• Analyze Interactions and Feedbacks

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Focus on Overriding Issues

• How can inventory and inverse estimates of the
  North American sink be reconciled?
• 1.8 Pg v. 0.3 Pg
• How can carbon stock changes due to management
  practices be distinguished from changes due to
  other factors?
• CO2 fertilization, nitrogen deposition
• Climate variability, climate change

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Focus on Overriding Issues

• How will ecosystem services be affected by global
  change?
• What carbon budget is compatible with different
  stabilization levels given feedbacks?
• Ocean CO2 uptake
• Climate change and CO2 fertilization impact on
  NEP
• Changes in forest cover impact on albedo
• Climate change impacts on methane emissions

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Global Soil and Vegetation Carbon
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Atmospheric CO2 Concentrations Due to
Business-as-Usual Emissions (IPCC IS92a)
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Temperature Rise Over LandDue to IPCC
Business-as-Usual (IS92a) Emissions
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Impact of Carbon Cycle Feedbacks on CO2
Concentration (WRE550 Emissions)
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Impact of Carbon Cycle Feedbacks on Stabilisation
Levels