Global Climate Change First Fridays Talk 4 November 2005 Crispin Pierce, Ph.D

Overview What is global climate change? What are the historical temperature and weather pattern trends? The greenhouse effect. How has human activity altered climate? Costs of extreme weather events. Greenhouse gas generation and half- lives. Global warming in Wisconsin. What can be done.

What is Global Climate Change? Average air, water, soil temperatures Mean sea level changes Patterns of precipitation, wind currents, water currents, storms, tornados, hurricanes, el nino and la nina. Droughts and floods

Historic Temperature Trends Surface temperature Water temperature Atmospheric temperature (satellite data)

Measured Sea Level Changes

The Greenhouse Effect

Human Influence Greenhouse gas emissions Aerosol emissions Deforestation

Costs of Extreme Weather Events

Overall framework

Greenhouse Gas Half-Lives Due to the slow conversion of greenhouse gases such as CO 2 into other chemicals (e.g., H 2 CO 3, carbonic acid), human additions will take hundreds of years to balance. The half-life of CO 2 in the atmosphere is about 100 years.

Global Warming in Wisconsin

Likely effects include: –Warmer, wetter winters –Hotter, drier summers (increased heat- related deaths, particularly amongst the elderly). –More frequent forest fires. –More frequent drought, damaging crops. –Less water available for drinking, showers, and irrigation.

What can be done? Stabilize world population –Greater foreign aid to support health Reduce AIDS incidence Provide food and clean water Increase health services, including birth control options –Support expanded roles for women internationally To own property To hold public office To work outside the home

Revise energy policies –Mandate conservation and fuel efficiency. –Shift towards non greenhouse gas- producing sources: wind, solar, hydroelectric, and nuclear.

Protect and expand carbon dioxide sinks –Protect forests. –Plant additional native trees. –Provide landowners with financial incentives to maintain wooded areas.

Make smart personal choices –Modest housing near city centers. –Fuel-efficient cars driven sparingly. –Vegetable/fruit/grain-centered diet.