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Image from the Denali Repeat Photography Project. Not far from the Teklanika Campground, this photo pair shows an increase in spruce density at lower areas where spruce previously occurred, and an expansion of spruce at higher elevations (visible in the upper right of photos).
Leslie A. Viereck (1958), Leslie A. Viereck (2001)
The Denali Repeat Photography project has assembled more than 200 photo pairs taken across a large cross-section of Denali from the low-lying black spruce forests to ice fields high in the Alaska Range. What unites these disparate images is that they show repeated views of a single location at different moments in time. The interval separating the pairs of photos varies greatly – from just a few years to longer than a century.
The Repeat Photography Project began in 1997 with a systematic search of the archives at Glacier National Park. Since 1997 over sixty photographs have been repeated of seventeen different glaciers. Thirteen of those glaciers have shown marked recession and some of the more intensely studied glaciers have proved to be just 1/3 of their estimated maximum size that occurred at the end of the Little Ice Age (circa 1850). In fact, only 26 named glaciers presently exist of the 150 glaciers present in 1850.
Chronolog is a photo monitoring tool that allows community scientists to take photos and contribute to collections of repeated photographs at designated sites. At each Chronolog site, a placard is posted with instructions to submit your photos. You can also view time-lapses of the photos that others have contributed. Several parks host Chronolog sites to monitor change on trails, coastlines, vegetation, and more.
Digital Earth Watch (DEW) brings together biology, physics, chemistry, technology, art, engineering, and math in a project that supports environmental science field studies in middle schools, high schools, self-guided education, and citizen science. This site has free software, ideas for activities, and challenge questions.
Abstract: The Boston Museum of Science developed monitoring stations called PicturePosts as part of its Measuring Vegetation Health program. Despite their many educational applications, PicturePosts had not been implemented in an educational environment. To encourage and assist in their use, we formed an advisory board of educators who provided input and feedback as we developed an educator’s guide and installation and software manuals for PicturePosts. The educators’ impressions of the Posts support the program’s far-reaching potential to enhance science education.
