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The ABCs of Climate Change

What is the greenhouse effect? 

The “greenhouse effect” is a natural occurrence.  Energy from the sun passes through the atmosphere and is absorbed by the Earth’s surface - some of that energy is then emitted back to the atmosphere as heat.  A portion of the heat is absorbed by heat-trapping gases in the atmosphere (among them carbon dioxide (CO2) and methane (CH4)), which creates an insulating layer around the Earth.  The trapped heat, which would otherwise be released into space, raises the temperature of the atmosphere and, subsequently, the Earth’s surface.  Human activities that produce additional greenhouse gases increase the amount of heat trapped in the atmosphere, thus causing global warming and climate change.

What is global warming?

Global warming refers to the rise in the Earth’s temperature resulting from an increase in heat-trapping gases in the atmosphere.

What are the primary greenhouse gases (GHG)?

• Carbon dioxide (CO2)
• Methane (CH4)
• Nitrous oxide (N2O)
• Water vapor
• Other gases

What are some of the projected impacts of climate change?

• Species in natural ecosystems will attempt to migrate with the changing climate, but will differ in their degree of success.  Some ecosystems will either flourish or decline in health, at least over the short-term. 

• Human health may be affected by climate change through a number of mechanisms including extreme temperatures (i.e. heat waves), increased air pollution (i.e. leading to rises in asthma incidences) and an increase in disease-bearing vectors (e.g. mosquitoes).

To learn more about Climate Change, check out these programs.

• COG Regional Climate Challenge brochure
• Pew Center on Global Climate Change
• The Intergovernmental Panel on Climate Change (IPCC)
• Environmental Defense