All Things Considered, October 23, 2006 - About 70 years ago, pioneer aerial photographer Bradford Washburn flew over Alaska's glaciers, documenting their splendor while looking for mountain-climbing routes.

Now, a Boston photojournalist is following in his footsteps with a very different purpose. He's reshooting Washburn's images to demonstrate global warming's impacts. Ed Schoenfeld of CoastAlaska News reports from Juneau.

David Arnold sits on a bench outside a helicopter tour office, waiting for his charter flight. He shuffles through a collection of 1930s photographs showing Alaska glaciers from the air. They were taken by Washburn, a mountain-climber, mapmaker and museum director.

"The most remarkable thing about Brad's pictures is the artistic quality of them," Arnold says. "And actually, what you see today is the loss of art. The forces, the confrontations that so enamored him are gone."

The glaciers Washburn found were massive. But many have since lost much of their mass. Arnold's goal this day is to shoot the Mendenhall Glacier, in Juneau, and learn how it has changed since Washburn flew by in 1937.

A mountain-ringed ice field almost the size of Rhode Island is the Mendenhall Glacier's birthplace. The fractured, twisting river of ice wends its way down a dozen miles of high-walled valley.

Tour buses bring more than 350,000 people a year to gawk at its face, a wall more than 100 feet high and a mile wide.

Washburn found a far calmer scene when he took his photograph of Mendenhall 70 years ago. That image shows the glacier flowing into a tree-spotted valley, largely free of human habitation.

Today, Arnold finds the area cluttered with shopping malls, suburban subdivisions and a modern airport. That makes replicating Washburn's shot difficult.

"Shooting the Mendenhall in Juneau is the first time I've looked at so much change, human change, just buildings and development," he says. "And that turned out to be, for me, very disorienting."

But Arnold is ready to try. He climbs into the helicopter, prepared to juggle his cameras while coping with wind, cold fingers and tearing eyes. But according to biographer Mike Sfraga, it's nothing compared to what Washburn had to handle.

"At 16,000 to 18,000 feet, he would hang out of the plane, and his pilot would do choreography over the mountains," Sfraga says of Washburn's daredevil techniques.

Sfraga says Washburn's passion overcame the challenges of heavy camera gear and cold temperatures.

It took two flights in the helicopter, but Arnold found Washburn's angle. "I was amazed at how much the glacier had retreated," Arnold says.

Arnold's photograph shows a smaller, thinner Mendenhall. Its crumpled, white image is much less of a presence than in Washburn's earlier image.

"I suppose if you're going to be poetic about matching up the development with the demise, or the slowly shrinking glacier, this is the shot," Arnold says.

Arnold is working for the same institution Washburn directed for 40 years, the Boston Museum of Science. Eventually, his shots will be paired with Washburn's for public display.