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 simulation allows the user to project CO2 sources and sinks by adjusting the points on a graph and then running the simulation to see projections for the impact on atmospheric CO2 and global temperatures.

This video highlights a variety of climate change research initiatives from scientists at the University of Colorado, Boulder. It describes the changing dynamics of Antarctic ice sheets and the impacts of reduced Arctic sea ice. The video illustrates the excitement of this research through interviews and video clips of scientists in the field.

In this lab activity, students use a chemical indicator (bromothymol blue) to detect the presence of carbon dioxide in animal and plant respiration and in the burning of fossil fuels and its absence in the products of plant photosynthesis. After completing the five parts of this activity, students compare the colors of the chemical indicator in each part and interpret the results in terms of the qualitative importance of carbon sinks and sources.

This video features research conducted at University of Colorado's Institute of Arctic and Alpine Research, which studies isotopes of hydrogen trapped in ice cores to understand climate changes in the past.

This video, from ClimateCentral, features a team of scientists from the Northern Greenland Eemian Ice Drilling Project (NEEM), who study atmospheric air bubbles trapped in an ice core from a period in Greenland's ice sheet which began about 130,000 years ago and lasted about 10,000 years; a period known as the Eemian. The air bubbles from the ancient atmosphere - all aligned on the same time scale - reveal what happened with climate change over that period of time.

The NOAA Sea Level Trends map illustrates U.S. regional and some international trends in sea level, with arrows representing the direction and magnitude of change. Students can investigate sea level changes around the U.S. and some worldwide using an interactive map interface with supporting data plots and tables.

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 short investigation from Carbo Europe explores how temperature affects the solubility of carbon dioxide in water.

This static graph of changes in CO2 concentrations goes back 400,000 years, showing the dramatic spike in recent years.