Climate Change -- A U.S. Environmental Protection Agency website.

Climate Change: Impacts and Solutions -- A website of the David Suzuki Foundation, a science-based Canadian environmental organization.

CLIVAR: Climate Variability and Predictability -- A World Climate Research Programme website.

Global Climate Change -- A Pew Center website.

Global Warming: Frequently Asked Questions -- A National Climatic Data Center website..

Global Warming International Centre -- The website of the Global Warming International Centre, an international organization of scientists, policy makers and scholars.

Global Warming Science -- A website of the Union of Concerned Scientists.

Intergovernmental Panel on Climate Change (IPCC) -- The IPCC was established by the World Meteorological Organization and the United Nations Environment Programme.

A Paleo Perspective on Global Warming -- A National Oceanic and Atmospheric Administration website produced by the NOAA Paleoclimatology Program.

United States Global Change Research Program -- The Global Change Research Program is a program overseen by the Executive Office of the President.