Global warming is the sustained increase in the average temperature of the earth's atmosphere. Human activity contributes to this change through the buildup of heat-trapping greenhouse gases. Over time, this increase may be sufficient to cause climatic change, including raising sea levels, altering precipitation patterns and changing water supplies and crop yields. Global warming could also affect human health, harm wildlife and damage fragile ecosystems. Through its monitoring activities, regulations and voluntary programs such as EnergyStar and WasteWise, the EPA encourages energy conservation and the use of alternative energy sources. By reducing the use of fossil fuels and promoting clean alternatives, the EPA is helping to minimize the buildup of heat-trapping industrial greenhouse gases.

Recommended EPA Web pages

• Global Warming
  Site gives information and links to information on global warming.
• Global Warming - Climate
  According to the National Academy of Sciences, the Earth's surface temperature has risen by about 1 degree Fahrenheit in the past century, with accelerated warming during the past two decades.
• Global Warming: Actions
  Today, action is occurring at every level to reduce, to avoid, and to better understand the risks associated with climate change.