Yale Glacier is a massive tidewater glacier in College Fjord, Prince William Sound, that originates at an elevation of 9,270 feet (2,826 m) between Mount Cardozo and Mount Einstein in the Chugach Mountains and flows generally southwest for 17 miles (27 km) to Yale Arm, about 48 miles (77 km) northeast of Whittier and 43 miles (69 km) west-northwest of Valdez, Alaska. Members of the 1899 Harriman Alaska expedition named the glacier for Yale University in New Haven, Connecticut. The Chugach Mountains in Southcentral Alaska are the northernmost of the ranges comprising the Pacific Coast Ranges along North America’s western edge. The range stretches about 250 miles (402 km) long and 60 miles (97 km) wide, extending from the Knik and Turnagain Arms of Cook Inlet in the west to Bering Glacier in the east, and is bounded on the north by the Matanuska, Copper, and Chitina Rivers. The highest point is Mount Marcus Baker, at 13,094 feet (3,991 m); however, with an average elevation of 4,006 feet (1,221 m), most summits are not particularly high. Nonetheless, its location along the Gulf of Alaska produces more snowfall than anywhere else in the world—averaging over 800 inches (2,032 cm) annually. The name ‘Chugach’ derives from ‘Cuungaaciq,’ a term in the Chugach Sugpiaq language originally used as a place name for several islands in Alutiiq territory. Over time it came to designate one of the Alutiiq dialects spoken on the Chugach Islands and the neighboring part of the Kenai Peninsula. The Chugach Sugpiaq people—Alutiiq or Pacific Eskimo—speak the Chugach dialect of the Alutiiq language. In 1898, US Army Captain William R. Abercrombie applied the name ‘Chugatch’ to the mountains surrounding Valdez.

During the Last Glacial Maximum, Prince William Sound was blanketed by the Cordilleran Ice Sheet. As the ice receded about 9,000 years ago, people migrated into the region. A prehistoric village at Uqciuvit—roughly 25 miles southwest of Yale Glacier—indicates occupation around 4,400 years ago, though it was likely abandoned when mountain glaciers advanced during the Little Ice Age. In 1794, Lieutenant Joseph Whidbey reported College Fjord’s glaciers during a survey led by Captain George Vancouver; his party advanced to within 12 miles before floating ice blocked their path. In 1887, Samuel Applegate, aboard the schooner Nellie Juan, surveyed the area without approaching the glacier terminus. His map of Yale Glacier suggests that the terminus lay near or just beyond College Point. In 1898, a US Army team led by Edward F. Glenn, Joseph C. Castner, and Walter C. Mendenhall approached the enormous glaciers at the head of College Fjord aboard the steamship Valencia, dubbing them ‘Twin Glaciers.’ Later that year, during the Harriman Expedition on the steamship George W. Elder, the glacier in the fjord’s east arm was named for Yale University. Henry Gannett and Grove Karl Gilbert studied the glaciers as fully as their brief visit allowed while others documented the scene with numerous photographs. In 1908–09, a US Geological Survey team—including Ulysses S. Grant and Daniel F. Higgins of Northwestern University—photographed, mapped, and described the glacier in detail. Aerial photographs by Bradford Washburn in 1937 show the glacier terminus roughly aligned with its 1899 position during the Harriman Alaska Expedition. The images reveal several tributary valley glaciers descending the fjord’s east wall, with the two nearest the terminus having detached from Yale Glacier. By 2006, Yale Glacier had retreated some 3.7 miles from its 1937 position and thinned markedly, in places by over 820 feet. All eastern tributaries had similarly retreated and detached.

Since 1931, terminus fluctuations of several tidewater glaciers in College Fjord have been monitored by surveying, photogrammetry, and, most recently, satellite imagery. Observations of Yale and Harvard Glaciers—two parallel bodies that share the same Chugach Mountains snowfield—suggest that their terminus behavior relates more to the tidewater glacier cycle than to direct effects of climate change, despite many indirect links. Since 1931, Harvard Glacier has advanced at an average rate of nearly 66 feet (20 m) per year, while adjacent Yale Glacier has retreated about 164 feet (50 m) per year—almost twice Harvard’s rate. In general, tidewater glacier termini result from complex interactions among fjord depth, ice thickness, and calving rate. Tidewater glaciers undergo a periodic cycle in three phases. In the first phase, the glacier slowly advances down the fjord through deep water by pushing or maintaining a submarine moraine at its front. This moraine is sustained by continuous erosion along the sides and bottom, coupled with deposition at the front, which greatly reduces iceberg calving. In the second phase, the terminus remains nearly stationary in the shallow water created by the submarine moraine. In the third phase, the terminus detaches from the moraine and retreats rapidly as its terminal face is exposed to deep water. The resulting increase in calving rate exceeds the ice supply, triggering dramatic retreat up the fjord. Retreat continues until the glacier stabilizes on another submarine shoal or grounds at the head of the fjord, where it can form a new terminal moraine. Yale Glacier appears near the end of its catastrophic retreat phase, while Harvard Glacier is still advancing. Climatic changes—such as overall warming that limits the ice supply—may trigger or interrupt this cycle. Read more here and here. Explore more of Yale Glacier and College Fjord here: