Documenting Glacial Change

WGBH, WGBH

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.

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Notes from our reviewers

The CLEAN collection is hand-picked and rigorously reviewed for scientific accuracy and classroom effectiveness. Read what our review team had to say about this resource below or learn more about how CLEAN reviews teaching materials.

Great to use in a geography lesson as well as a science lesson. Original photographs are available on the NSIDC website: [http://nsidc.org/data/glacier_photo/index.html] Glaciers are changing rapidly. Search for up to date imagery and data while teaching this topic.
The Background Essay gives a nice overview of causes and effects of glacial retreat. The effect on the immediate environment, once glaciers recede, is readily apparent. Receding glaciers leave telltale signs of their presence in the landscape. With the ice gone, glaciated terrain may be characterized by an eroded valley bed and debris piles, ripe for colonization by pioneer plant species. Comments from expert scientist: The background essay excels in explaining many basic and important concepts. In order to understand why glaciers respond to climate changes, the concept of mass balance is crucial, and the explanation is straightforward and clear. Could be updated with more recent images.
Easy to see the changes over time. Discussion questions are provided. Image pairs are supported by an essay and links to other resources, both print and media. A possible misconception is that the images are taken in different seasons, which accounts for the different amounts of snow and ice. Reinforce the idea that the pairs of images are taken at the same time of year.