Anthropogenic Climate Change

Global Temperature is Increasing

How We Know This

• Measured data• Natural indicators• Observation• Ice• Weather• Wildlife

Natural Forcing

Source: IPCC (Intergovernmental Panel on Climate Change)

- “Radiative forcing is a measure of the influence a factor has in altering the balance of incoming and outgoing energy in the Earth-atmosphere system and is an index of the importance of the factor as a potential climate change mechanism. In this report radiative forcing values are for changes relative to preindustrial conditions defined at 1750 and are expressed in Watts per square meter (W/m2)” -IPCC

Source: “High-resolution carbon dioxide concentration record 650,000–800,000 years before present”

-Compilation of CO2 records and EPICA (European Project for Ice Coring in Antarctica) Dome C temperature anomaly over the past 800 thousand years- Changes in past atmospheric carbon dioxide concentrations were determined by measuring the composition of air trapped in ice cores from Antarctica-atmospheric carbon dioxide is strongly correlated with Antarctic temperature throughout eight glacial cycles

Source: United States Global Change Research Program (2009)

Anthropogenic Forcing

• s

Source: NOAA (National Oceanic and Atmospheric Administration)

Greenhouse Gases

• CO2, N2O, CH4, H2O, CFCs, O3

• Energy absorption– Larger gases vibrate when struck– Think about ozone

• CO2 absorbs infrared emitted from Earth’s surface• Bouncing around of energy keeps surface warm• Net positive forcing of 1.6 W/m2

• Varying atmospheric lifespan

Source: http://centerforoceansolutions.org/climate/impacts/cumulative-impacts/storm-intensity/

Source: Greenpeace

Source: U.S. Environmental Protection Agency

Source: U.S. Environmental Protection Agency