Communicating and Learning About Global Climate Change:

Opening Remarks

John P. HoldrenDirector, The Woods Hole Research Center

Teresa & John Heinz Professor of Environmental Policy, Harvard University

President, American Association for the Advancement of Science

Global Climate Change Town Meeting Annual Meeting of the AAAS

San Francisco, 17 February 2007

The scientific evidence is clear: global climate change caused by human activities is occurring now, and it is a growing threat to society. Accumulating data from across the globe reveal a wide array of effects: rapidly melting glaciers, destabilization of major ice sheets, increases in extreme weather, rising sea level, shifts in species ranges, and more. The pace of change and the evidence of harm have increased markedly over the last five years. The time to control greenhouse gas emissions is now.

from the Climate Change Statement of the AAAS Board, released 2-18-07

• Global climate change is the most dangerous environmental problem humans have ever created.

• It is also the most difficult environmental problem humans have ever created.

• But there is much that individuals, firms, & governments can do to reduce the danger.

Climate change: complex & interdisciplinary

• SCIENCE

– what climate is and how it works;

– how global climate has been changing and why;

– how it’s likely to change in the decades ahead;

– what the impacts are likely to be on farms, forests, fisheries, health, property, ecosystems…

• TECHNOLOGY

– the role of humans & their technology in causing climate change;

– technological options for mitigating climate change;

– technological options for adapting to it.

Complex & interdisciplinary (continued)

• ECONOMICS

– population growth & economic growth as climate-change drivers

– costs of abatement, adaptation, and impacts

– consequences of alternative regimes of action & inaction for economic growth, employment, trade

• POLITICS & POLICY

– policy options and their impact on outcomes

– actors and interests in the climate debate…and the evolution of perceptions & interests over time

– finding a global climate-policy framework that is adequate, equitable, and attainable

– uncertainty and prudence in public policy on climate

Climate change as a teaching opportunity

The physics & geometry of Earth’s orientation to the sun

Climate change as a teaching opportunity

PHYSICS:Interaction of electromagneticradiation withmatter

www.livephysics.com

Climate change as a teaching opportunity

Physics: energy flows in the atmosphere

Physics: water, ice, and sea-level rise

Climate change as a teaching opportunity

Climate change as a teaching opportunity

CHEMISTRY

carbon in fossil fuels and combustion

coal ≈ CH

oil ≈ CH2

natural gas ≈ CH4 + a bit more

so, e.g., burning oil entails…

CH2 + 3/2 O2 CO2 + H2O

Climate change as a teaching opportunity

BIOCHEMISTRY

photosynthesis

6 CO2 + 12 H2O C6H12O6 + 6 H2O + 6 O2

(Trees are made of CO2 and water!)

respiration

C6H12O6 + 6 O2 6 CO2 + 6 H2O

anaerobic decomposition

C6H12O6 3 CO2 + 3 CH4

Climate change as a teaching opportunity

Earth science: the carbon cycle

True color MODIS composite image – late March 2000Climate change as a teaching opportunityClimate change as a teaching opportunity

Geography: remote sensing

Mato Grosso State, Brazil, 2004

Climate change as a teaching opportunity

Geography: land-use & deforestation

Climate change as a teaching opportunity

Earth science: winds & jet streams

Climate change as a teaching opportunity

Earth science: ocean currents

Earth science: how hurricanes work

Climate change as a teaching opportunity

Climate change as a teaching opportunity

Earth science: climate & life over geologic time

Climate change as a teaching opportunity

Probability and statistics of climate & weather

Climate change as a teaching opportunity

Ecology: interaction of organisms with a changing environment

Climate change as a teaching opportunity

Geography: climate-related health impacts

World Health Organization estimates of climate-change-related increases in mortality for the year 2000

Climate change as a teaching opportunity

Engineering: technology for CO2 capture

Geology: formations that can store CO2 Climate change as a teaching opportunity

Systems analysis / integrated assessment

Climate change as a teaching opportunity

Source: National Science Board, Science & Engineering Indicators 2004, Ch 7.

Sociology: public-opinion pollingClimate change as a teaching opportunity

Climate change as a teaching opportunity

Political science: leadership