Endicott Arm and Dawes Glacier

The Endicott Arm is a fjord in the Fords Terror Wilderness area of the Tongass National Forest, Southeast Alaska. It stretches about 30 miles (48 km) from the Sumner Strait to the Dawes Glacier, its terminal glacier.

The fjord is a classic U-shaped valley, carved by glacial activity during the Pleistocene period, with steep granite cliffs rising sharply from the water—some exceeding 3,000 feet (900 m). The walls were streaked with waterfalls cascading from hanging valleys, a result of tributary glaciers that once fed the main ice stream.

The Dawes Glacier is a temperate valley glacier, a glacier that exists in a region where the ice is at or near its melting point, allowing for dynamic flow and calving.

The Dawes Glacier originates in the Coast Mountains, specifically from the Juneau Icefield, a massive icefield spanning 1,500 sq mi (3,900 sq km) and feeding over 40 glaciers, including the Mendenhall and Taku.

The glacier flows downhill under its own weight, driven by gravity and the pressure of accumulating snow in the upper accumulation zone. It typically moves at rates of 1–3 feet per day in the lower section.

The Dawes Glacier is an active tidewater glacier, meaning it terminates in the sea (Endicott Arm). Calving events - where chunks of ice break off the glacier face - are frequent and dramatic, often producing icebergs that float in the fjord.

Blue ice is dense, ancient ice often appears blue due to the absorption of red and yellow light wavelengths, with blue light scattering back to the observer.

Crevasses are large cracks on the glacier surface, formed by differential stress as the ice moves over uneven terrain.

Moraines are accumulations of rock debris (lateral, medial, or terminal) carried along the glacier’s sides or surface, deposited as the ice melts.

Harbor seals often haul out on icebergs near the glacier face, using them as platforms for resting and pupping. The fjord also supports salmon, halibut, and various seabirds (e.g., cormorants, guillemots). The surrounding cliffs host mountain goats and, occasionally, brown bears foraging at low tide.Read more