by Ned Rozell
December 31, 2004
William Field, U.S. Geological Survey photo.
"When you put pictures in front of somebody, you don't have to say anything," said Molnia, who works for USGS in Reston, Virginia, but has a home in Fairbanks. Molnia spent the summer of 2004 traveling to Glacier Bay and Kenai Fiords, trying to find the exact spots where earlier photographers captured glaciers on film. Sometimes finding the cairns (rock piles) of glaciologists who took photographs from the spots decades earlier, Molnia snapped new photos, including the color photo of Muir and Riggs glaciers that appeared on the front page of the December 17, 2004 edition of the San Francisco Chronicle and accompanied a story about Alaska's melting glaciers by David Perlman.
as photographed in 2004.
Photo by Bruce Molnia.
"All the glaciers in the Arctic National Wildlife Refuge are retreating from their most extended positions thousands of years ago, and the only scientific explanation is climate change," said Nolan, as quoted by Perlman in the Chronicle article.
Tape took the laser pointer at the podium and displayed several pairs of photographs of Alaska's North Slope that show the encroachment of shrubs. A government photographer took the huge-negative, Ansel-Adams style black and white originals in the 1940s, and Tape duplicated them with a digital camera in recent years. He explained how shrubs make the North Slope warmer by absorbing more sunlight and how shrubs along riverbanks have restricted river channels and perhaps attracted more moose north over the Brooks Range. The changes he has detailed along with Matt Sturm and Charles Racine of the Cold Regions Research and Engineering Laboratory have all happened in about 60 years, "a blink of an eye in geological time," Tape said.
The use of photographs to document change in the north is a technique more scientists are using, enough that it merited a poster session on the subject at the conference. Molnia said his future work includes revisiting about 100 of the places in Denali National Park that mountaineer and photographer Brad Washburn photographed in the 1930s and 1940s to compare changes from then until now. Molnia tried to duplicate them in summer of 2004, but the air was too smoky. Along with documenting changes in Alaska Range glaciers, Molnia will also benefit from changes in technology since Washburn climbed the peaks.
"Brad used 60-pound cameras for his work," Molnia said. "We'll do a lot of our stuff with digital cameras."
This column is provided as a public service by the Geophysical Institute, University of Alaska Fairbanks, in cooperation with the UAF research community. Ned Rozell ( email@example.com ) is a science writer at the institute.