Climate Change:The Basics

What is climate change and

why is it happening?

Questions I hope to answer…

1. What is the difference between the greenhouse effect, climate change and global warming?

2. What proof do we have that climate change is happening?

3. Why is it happening?

The Greenhouse Effect

The Earth is surrounded by a thin layer of gasses we call greenhouse gases. These gases are what make up our atmosphere.

Source: NASA

The Sun’s energy passes through the car’s windshield.

This energy (heat) is trapped inside the car and cannot pass back through the windshield, causing the inside of the car to warm up.

The Greenhouse Effect

© 2007National Wildlife Federation

The thickness of the atmosphere and the concentration of its gases influence the surfacetemperature on any planet. Source: Will Steger Foundation, Elizabeth Andre

What’s the difference?GLOBAL WARMINGIs the increase of the Earth’s average surface temperature due to a build-up of greenhouse gases in the atmosphere.

CLIMATE CHANGEIs the long-term changes in climate, including average temperature and precipitation. It recognizes that, although the average surface temperature may increase, the regional or local temperature may decrease or remain constant.

© 2007National Wildlife Federation

What does “average” mean?• Climate is the average

weather conditions over time.

• Global warming refers to an increase in the Earth’s average temperature.

Source: http://en.wikipedia.org/wiki/User:Dragons_flight

How Global Warming Works

Carbon Dioxide (CO2)

© 2007National Wildlife Federation

Fossil fuels (coal, oil, natural gas)

What proof do we have?

Temperature (Northern Hemisphere) CO2 Concentrations

1000 years of CO2 & temperature data

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© 2007National Wildlife Federation

Shrinking of Fedchenko Glacier in Tajikistan Source: Photo: V. Novikov (taken in summer

2006); data from the Tajik Agency on Hydrometeorology

Portage GlacierAlaska

1914 2004

Photos: NOAA Photo Collection and Gary Braasch – WorldViewOfGlobalWarming.orgNWF/2007

Source: Church, J.A. and White, N.J. (2006). A 20th century acceleration in global sea-level rise. Geophysical Research Letters, 33, L01602

Climate Change in the Midwest

• Temperatures are rising, especially in winter.

• Extreme rainfall events (24-hr and 7-day) are more frequent.

• Winters are shorter.

• Lake ice melts earlier, especially on smaller lakes.

Source: Great Lakes Report, Union of Concerned Scientists

Why is climate change happening?

CO2 and the Industrial Revolution Source: TP Whorf Scripps, Mauna Loa Observatory, Hawaii, Institution of Oceanography (SIO), University of California La Jolla, California, United States, 1999

Burning of Fossil Fuels

Pollution from coal, natural gas, and oil

Pollution from coal, natural gas, and oil

Pollution from coal, natural gas,

and oil

© 2007National Wildlife Federation

CreditsThank you to the National Wildlife Federation for giving permission to use slides from Climate Classroom.

Hickey, Laura. (2007). Whats up with global warming? Retrieved, October 10, 2007, from www.climateclassroom.org, www.nwf.org.

The Great Lakes report, as well as other regional reports, can be downloaded from the Union of Concerned Scientist website at:

http://www.ucsusa.org/greatlakes/glchallengereport.html