This short video, adapted from NOVA, explains how Earth's position relative to the Sun might be responsible for the dramatic shift in the climate of what is now the Saharan nation of Djibouti.

This series of visualizations show the annual Arctic sea ice minimum from 1979 to 2015. The decrease in Arctic sea ice over time is shown in an animation and a graph plotted simultaneously, but can be parsed so that the change in sea ice area can be shown without the graph.

This article and slide show from the New York Times, features several scientists from the University of Alaska, Fairbanks, who study the effects of thawing permafrost in Alaska.

This video features scientists in New Zealand's Southern Alps, examining samples from the rocky landscape once dominated by glaciers. Their research, combined with other climate records, has revealed a link between glacial retreat and rising levels of carbon dioxide in the air.

This video describes why tropical ice cores are important and provide different information than polar ice cores, why getting them now is important (they are disappearing), and how scientists get them. The work of glaciologist Lonnie Thompson is featured, with a focus on his work collecting cores of ice from high mountain glaciers that contain significant data about past climate change.

A collection of repeat photography of glaciers from the National Snow and Ice Data Center (NSIDC). The photos are taken years apart at or near the same location, and at the same time of year. These images illustrate how dramatically glacier positions can change even over a relatively short period in geological time: 60 to 100 years. Background essay and discussion questions are included.

This video is part two of a seven-part National Academies series, Climate Change: Lines of Evidence. The video outlines, with the use of recent research and historical data, how we know that the Earth is warming.

This short video clip summarizes NOAA's annual State of the Climate Report for 2009. It presents a comprehensive summary of Earth's climate in 2009 and establishes the last decade as the warmest on record. Reduced extent of Arctic sea ice, glacier volume, and snow cover reflect the effects of rising global temperature.

This is an interactive website that provides descriptive information and data related to ten key climate indicators. These climate indicators and related resources show global patterns and data that are intuitive and compelling teaching tools.

A detailed Google Earth tour of glacier change over the last 50 years introduces this topic in an engaging way. Students are then asked to select from a group of glaciers and create their own Google Earth tour exploring key characteristics and visible changes in that glacier.

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