AOSC675: Carbon Cycle and Climate: Past, Present and Future

Instructor: Prof. Ning Zeng

Progress and Study Guide
Reading Assignments
Books, Grading, Office Hours
Lecture notes
Student Projects

This course introduces the fundamentals of the Earth's carbon cycle, a key biogeochemical cycle that controls Earth's climate and life.  The course will focus on the changing characteristics of the carbon cycle on several timescales, ranging from geological, glacial-interglacial, interannual-interdecadal, and the more recent anthropogenic influence on carbon cycle and climate, as well as the future carbon-climate interaction in global warming scenarios. The carbon cycle in the atmosphere, land, ocean and the biosphere will be addressed.  The underlying human activities such as fossil fuel burning and deforestation  that are responsible for the increase in the atmosphere CO2 and our future options in dealing with the carbon problem such as alternative energy, carbon sequestration and management, as well as the relevant policy and social aspects will also be discussed.

Sample questions we will examine include:
How and why is CO2 variability related to El Nino?
What is the so-called 'missing' carbon sink, i.e., where has all the fossil fuel carbon gone?
How true is the CO2 theory of climate change?
How strong is carbon-climate feedback in a global warming world?
What are the potential and impacts of various carbon management/sequestration schemes?


1. Fundamentals  (1 week)
    Historical background
    The natural carbon cycle
    The anthropogenically altered carbon cycle

2. Climate basics (1-2 weeks)
    Fundamental controls of Earth's climate: energy balance
    Greenhouse effect
    One-layer atmosphere model
    General circulation of the atmosphere: Global patterns of wind, pressure, precipitation and temperature
    Hadley and Walker Circulation, mid-latitude storms
    Short-term climate variability: ENSO, NAO, monsoons  
    Climate sensitivity and climate feedbacks
    Climate projection
    Impact and vulnerabilities

3. Processes underlying the natural carbon cycle (2 weeks)
    Seasonal cycles

4. Variability of the carbon cycle (1 week)
    The Mauna Loa CO2 record: many tales it tells
    ENSO, drought, disturbances such as fire
    other modes of variability
    Recent warming induced changes, espeicially in the arctic region

5. Carbon cycle change on geological timescales (1-2 weeks)
    The faint young Sun paradox
    Last 500 million years
    Glacial-interglacial cycles

6. Sources and sinks of anthropogenic carbon (2 weeks)
    Fossil fuel emissions
        Origin of coal, oil, gas; van Kevelen Diagram: transformation of biomass to fossil fuel
        Fossil fuel and energy use; Energy vs carbon content
        Energy Consumption, economics and CO2 emissions      
    Land Use: deforestation and regrowth
    The 'missing' (residual) carbon sink on land
    Sinks in the ocean and a lot more
    Closing the carbon budget

7. What's happening to the carbon cycle now and future projections (1 week)
    Recent changes
    Integrated assessment
    Carbon-climate feedbacks

8. Carbon management, energy use and options for the future (1 week)
      Rnewable energy resources
      Carbon sequestration

Grading Method
Students will be evaluated based on participation (20%), light homework/quiz (20%), reading/presentation (30%), and a final project (30%).

Reference books (no required text book)

The Earth System. Lee Kump, James Kasting and Robert Crane. Prentice Hall, 1999.

W.H. Schlesinger (Editor), Academic Press,  ISBN 0-08-044642-6 | 6/8/2005
  Required reading: summaries on geological (Sundquist, Ch8.09) and modern (Houghton, Ch8.10) carbon cycle

Global Warming: Understanding the Forecast  (Introduction to climate change, also a bit carbon cycle)
David Archer, Blackwell Publishing, 2008

The Global Carbon Cycle: Integrating Humans, Climate, and the Natural World            (Good summaries of current research)
C. B. Field and M. R. Raupach (editors);  Island Press, 2004. ISBN 1559635274

Earth System Science: From Biogeochemical Cycles to Global Changes                (Concepts (chapter by Rodhe), and specific topics)
by Michael Jacobson, Robert J. Charlson, Henning Rodhe, Gordon H. Orians
Academic Press; 1st edition (February 15, 2000)  ISBN: 012379370X

Earth's Climate: Past and Future
William Ruddiman


        Prof. Ning Zeng
        Office: ATL 2417
        Phone: (301) 405-5377    Fax: (301) 314-9482

Office Hour
After class, drop by or by appointment

Sample student projects from the past