Global Climate Change: The Heart of the Matter

• What we can see (observations)

• What is causing it (causes and evidence)

• What can happen (projections)

• What we can do (responses)

The Heart of the Matter

• What we can see (observations)

• What is causing it (causes and evidence)

• What can happen (projections)

• What we can do (responses)

The Heart of the Matter

http://data.giss.nasa.gov/gistemp/graphs/

Warming is Unequivocal

http://data.giss.nasa.gov/gistemp/maps/

And Not Uniform

http://www.climatecentral.org/blogs/royal-weddings-and-climate-change1/

NASA

2003 European Heat Wave

After Schaer et al., 2004

Switzerland Summer Temperature

2003 European Heat Wave

• What we can see (observations)

• What is causing it (causes and evidence)

• What can happen (projections)

• What we can do (responses)

The Heart of the Matter

Ice Core Records

Radiative Forcing

IPCC, 2007Black = ObservedGold = Human and Natural ForcingsBlue = Only Natural Forcings

Fingerprint Analysis

• What we can see (observations)

• What is causing it (causes and evidence)

• What can happen (projections)

• What we can do (responses)

The Heart of the Matter

UCS

UCS

Projected Changes in CA Summer Temperature

Diminishing Sierra SnowpackPercentage Remaining, Relative to 1961-1990

UCS

Tipping elements in the Earth system

Lenton et al., PNAS 2008

• What we can see (observations)

• What is causing it (causes and evidence)

• What can happen (projections)

• What we can do (responses)

The Heart of the Matter

Mitigation

Adaptation

Climate Stabilization

Raupach et al., 2007

Regional CO2 Emissions

2004 2000-2004Growth

Davis and Caldeira, 2010

Davis and Caldeira, 2010

IPCC, 2007

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Extreme Events: Heat

IPCC, 2007

Extreme Events: Heat

29