see also Climate and Meteorology

• Global Warming Facts & Our Future - explores the latest scientific information from the National Academy of Sciences: Is our climate warming? Are humans causing it? What might be the effects? What can be done? Learn about the greenhouse effect, the carbon cycle, & past changes in our climate. See predicted changes & how they could affect sea levels, agriculture, & ecosystems. Find out about options for reducing CO2 emissions.
• USGS Global Change Research - Earth Surface Dynamics - more technical resource website describes climate change research at the USGS, but contains useful links to many climate investigations and publications.

Areas

• U.S. Antarctic Program - aims to understand the world's coldest, windiest, driest, and harshest continent -- its ecosystems and its effects on global processes such as climate. Read breaking news from a newspaper written in McMurdo Station, Antarctica. Learn about important discoveries. See articles about a killer crater found under the ice and the melting of polar ice sheets.

Western US

• Effects of Climatic Variability and Land Use on American Drylands - resources about global change in the US and Southwest (including California)
• Investigating Climate Change of Western North America - fact sheet about how the California Current in the Pacific Ocean drives the climate of the western U.S.

Gases

Carbon Cycle Science Program - links to information and educational resources related to the carbon cycle and greenhouse gases.

USGS Carbon Cycle Research - about the impacts of greenhouse gases on vegetation and climate change.

Exchanges of Greenhouse Gases, Water Vapor, and Heat at the Earth's Surface - research into the exchange of greenhouse gases (notably: carbon dioxide (CO 2), methane, and nitrous oxide), water vapor, and heat between Earth's land and water surfaces and the overlying atmosphere.

Volcanic Gas - fact sheet describes gases released by volcanoes which contribute to the ongoing evolution of the atmosphere.

Specific

USGS on El Niño - refers to a warm ocean current that typically appears around Christmas-time and lasts for several months, get a general overview of the science of El Niño, and provides links to resources that discuss the weather's impact on floods, landslides, coastal hazards, climate, etc.