This figure, the famous Keeling Curve, shows the history of atmospheric carbon dioxide concentrations as directly measured at Mauna Loa, Hawaii. This curve is an essential piece of evidence that shows the increased greenhouse gases that cause recent increases in global temperatures.

This NASA animation of the Five-Year Average Global Temperature Anomalies from 1881 to 2009 shows how temperature anomalies have varied in the last 130 years. The color-coded map displays a long-term progression of changing global surface temperatures from 1881 to 2009. Dark red indicates the greatest warming and dark blue indicates the greatest cooling.

As a segment in PBS's Coping with Climate Change series, Hari Sreenivasan reports on the actions the city of Chicago is taking to mitigate climate change in an urban landscape.

This detailed animated map shows global weather and climate events from the beginning of 2009 to the present. As the animation plays, specific events are highlighted to provide context and details for the viewer.

This Flash-based simulation explores the relationship between carbon emissions and atmospheric carbon dioxide using two main displays: (1) graphs that show the level of human-generated CO2 emissions, CO2 removals, and the level of CO2 in the atmosphere, and (2) a bathtub animation that shows the same information as the graphs. The bathtub simulation illustrates the challenges of reducing greenhouse gas concentrations in the atmosphere.

This humorous video suggests what might happen if a weather forecaster reported the weather in the context of climate change. There is a sharp contrast between the anchor focusing on short-term local concerns and the weather forecaster describing what is happening on a long-term global basis.

This collection of photos from the NASA Climate website features images related to global change. Not all images show change caused directly by climate change and energy use, and descriptive captions indicate causes for change in most of the images.

This NOAA visualization video on YouTube shows the seasonal variations in sea surface temperatures and ice cover for the 22 years prior to 2007 based on data collected by NOAA polar-orbiting satellites (POES). El NiÃo and La NiÃa are easily identified, as are the trends in decreasing polar sea ice.

This National Geographic video explains the origins of the El NiÃo Southern Oscillation using animations and shows the impacts on humans, wildlife and habitat, particularly in the United States.

This carbon calculator, developed by the EPA, guides students in calculating their carbon footprint and then using that information to make decisions about how to reduce their carbon emissions.