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.

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.

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

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 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 activity in a case study format explores ice loss from the Greenland ice sheet by way of outlet glaciers that flow into the ocean. Students do basic calculations and learn about data trends, rates of change, uncertainty, and predictions.