These graphs show carbon dioxide measurements at the Mauna Loa Observatory, Hawaii. The graphs display recent measurements as well as historical long term measurements. The related website summarizes in graphs the recent monthly CO2, the full CO2 Record, the annual Mean CO2 Growth Rate, and gives links to detailed CO2 data for this location, which is one of the most important CO2 sites in the world.

In this activity, students are introduced to tree rings by examining a cross section of a tree, also known as a 'tree cookie.' They discover how tree age can be determined by studying the rings and how ring thickness can be used to deduce times of optimal growing conditions. Next, they investigate simulated tree rings applying the scientific method to explore how climatic conditions varied over time.

This is the first of three short videos showcasing the dramatic changes in Alaska's marine ecosystems through interviews with scientists and Alaska Natives. This introduction to the impacts of climate change in Alaska includes interviews with Alaska Natives, commentary by scientists, and footage from Alaska's Arctic.

This activity develops student understanding of the relationship of weather and climate. Students use interview techniques to explore perceptions about local climate change among long-time residents of their community. Students then compare the results of their interviews to long term local temperature and precipitation records.

This video describes the role that dendrochronology plays in understanding climate change, especially changes to high elevation environments at an upper tree line. Dendrochronologists from the Big Sky Institute sample living and dead trees, describe how correlations between trees are made, and explain how tree cores record climate changes.

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.

Developed for Alaska Native students, this activity can be customized for other regions. Students interview elders or other long-term residents of the community to document their knowledge of local changes to the landscape and climate. Based on the information and photos they acquired from the interview, students return to photo locations to observe and record changes. Finally, they develop ideas about potential impacts of a warming climate to the ecosystem that surrounds them.

This series of visualizations show the annual Arctic sea ice minimum from 1979 to 2010. 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.

In this activity from the Deep Earth Academy, students divide into groups to read and discuss one of nine short articles (1-2 pages) about research done by the Ocean Drilling Program. These articles discuss our understanding about past climate based on collected data. These articles briefly describe the research conducted and the findings. Students use the information from the article to complete a write-up that they share with other students. An extension activity involves examining ocean drilling data using Google Earth.

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.