Repeat Photography: Capturing Change

Repeat photography is a technique that compares a historical photograph to a current one taken from the exact same location. At Glacier Bay, scientists can use this to learn more about how glacial movement changes a landscape and to document vast changes in glacier extent. In the following pictures, move the middle slider back and forth and watch the glaciers shift. Are they advancing or retreating? Also pay attention to the vegetation. Have plants re-colonized the land left behind by some of the glaciers?

 

Muir Inlet Scene 1880 and Today

Left image
Steamship passengers enjoy the icy scene in Muir Inlet
Credit: G.D. Hazard

Right image
Muir Inlet shoreline as seen today.
Credit: Bruce Molina/ USGS

 

Carrol Glacier in 1906 and 2003

Left image
Credit: Charles Wright/USGS

Right image
Credit: Bruce Molnia/USGS

 

Muir Inlet 1890 - and Today

Left image
Muir Inlet 1890

Right image
Muir Inlet Today

 

Lamplugh Glacier in 1941 and 2003

Left image
Credit: William Field

Right image
Credit: Bruce Molnia/USGS

Lamplugh Glacier has actually advanced almost a third of mile in the time between the two photos! Today, Lamplugh is stable/retreating.

 

Plateau Glacier in 1961 and 2003

Left image
Credit: M.T. Millet

Right image
Credit: R.D. Karpilo/NPS

Notice the two people in the center of the 1961 photo.

 

Reid Glacier in 1899 and 2003

Left image
Credit: G.K. Gilbert

Right image
Credit: Bruce Molnia/USGS

Reid inlet was once filled with glacial ice. 

 

View looking south from Muir Inlet

Left image
Glacier Bay's Icy Scene 1902

Right image
Glacier Bay Scene Today

Today Muir Inlet is virtually ice-free, but during the steamship era, careful navigation was required. 

 

Muir Glacier in 1892 and 2005

Left image
Credit: H.F. Reid

Right image
Credit: Bruce Molnia/USGS

Once the highlight attraction of Glacier Bay, the Muir Glacier filled the entire east arm of the bay. Today it is grounded and no longer touches the sea. 

 

Muir Glacier in 1941 and 1950

Left image
Credit: W.O. Field

Right image
Credit: W.O. Field

In the course of nine years, Muir Glacier retreated almost two miles. 

 

Bruce Molnia, USGS has studied glaciers throughout Alaska

USGS

Repeat Photography of Glacier Bay's Glaciers

How have the park's glaciers changed through time?

Repeat photography is a technique in which a historical photograph and a modern photograph, both having the same field of view, are compared and contrasted to quantitatively and qualitatively determine their similarities and differences. Discover how this technique was used at a number of locations in Alaska, including Glacier Bay National Park and Preserve, Kenai Fjords National Park, and the northwestern Prince William Sound area of the Chugach National Forest, to document and understand changes to glaciers and landscapes as a result of changing climate. Through analysis and interpretation of these photographic pairs, information is extracted to document Alaskan landscape evolution and glacier dynamics for the last century-and-a-quarter on local and regional scales and the response of the Alaskan landscape to retreating glacier ice.

Bruce Molnia, USGS