The goals of the Denali Repeat Photography project are to acquire, organize, and interpret matched
repeated photographs that capture landscape dynamics as they occur across time, and present them in
an informative manner accessible to a diverse audience.
To meet these goals, park staff looked far and wide, searching archives and personal collections and
working with cooperators including long-time Denali researchers such as Dr. Leslie Viereck to find
valuable historical images that would be useful for
studying landscape change. Park staff then made
numerous trips on foot, by vehicle, or by helicopter
to repeat, as closely as possible, the original historical
photographs. We also received donations of many
high-quality repeated photo-pairs from cooperators
such as Ron Karpilo, a geologist who has captured
numerous images of glacier change in the park.
Repeat photo pairs provide dramatic visual evidence
of recent changes in vegetation, water bodies, and
glaciers, among other elements of the landscape.
While there are unique natural and cultural history
vignettes revealed among this large set of photographs,
such as the draining of Bergh Lake, and the burial
of the Copper Mountain Cabin by river gravels, the
majority of photo pairs show change patterns that
appear to be operating on a larger scale.
In fact, the magnitude of observed changes in many of
these photo pairs suggests that a significant alteration
of the parks ecosystems is occurring in some areas,
likely caused by a warming climate and related
processes. Some of the primary types of change
documented include:
• (1) expansion of spruce into formerly treeless areas,
• (2) invasion of open wetland areas by woody
vegetation,
• (3) widespread colonization of formerly open
floodplains and terraces by vegetation,
• (4) shrinking ponds, and
• (5) receding glaciers and related features.
Figure 2. Beginning in 1938, the Thorofare River gradually
buried a park cabin.
In many cases, these changes appear directional; that is, they represent a qualitative shift in the
landscape mosaic, not simply a shift in vegetation due to succession or cyclical fluctuations in pond level
or glacial extent.
The Denali Repeat Photography project has helped to gather and make available to the public this
valuable visual evidence of these important and far-reaching changes that have the potential to
significantly affect park resources over the long term.
For more information on the National Park Service please visit their website (www.nps.gov)
May/Jun 2018
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THE DESERT LIGHT
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