This video discusses observations of two key warning signs of global change effects on the Southern Ocean: changes in Antarctic bottom water and ocean acidification.

This video explores the work of environmentalist John Hart, a Professor of Environmental Science at U.C. Berkley. In the Rocky Mountains of Colorado, Dr. Hart has established an experimental laboratory in which he has artificially created and maintained a 3-degree increase in surface temperature of a plot of land, and documented the impact on plant species occupying the plot.

Citizen scientist Anya, an indigenous Siberian girl, witnesses the changes in her community as a result of climate change after working with Woods Hole scientist Max Holmes' research team aboard her father's ship. She gets involved in collecting water samples to learn, and teach her schoolmates about, global warming.

This series of four animations shows how some of the key indicators of climate change (average global temperature, sea level, sea ice extent, carbon emissions) have changed in Earth's recent history.

This video segment, from the 'Earth: The Operators' Manual' featuring climate expert Richard Alley, shows how ice cores stored at the National Ice Core Lab provide evidence that ancient ice contains records of Earth's past climate - specifically carbon dioxide and temperature.

This graph, based on key ice core data sets and recent monitoring programs, shows the variations in concentration of carbon dioxide (CO2) in the atmosphere during the last 400,000 years.

In this activity, students reconstruct past climates using lake varves as a proxy to interpret long-term climate patterns and to understand annual sediment deposition and how it relates to weather and climate patterns.

This video considers the current estimates of sea level rise as possibly too conservative and discusses more recent data on ice melt rates coming from Antarctica and Greenland, showing rates of melt at up to 5 times as rapid. Scientists discuss what levels and rates of sea level rise have occurred in the past, including the Pliocene, which demonstrated 1m rise every 20 years.

This is a figure from the 2007 IPCC Assessment Report 4 on atmospheric concentrations of carbon dioxide, methane and nitrous oxide over the last 10,000 years (large panels) and since 1750 (inset panels).

This interactive visualization from the NASA Earth Observatory website compares Arctic sea ice minimum extent from 1984 to that of 2012.