The Kashteen Peninsula is located in Icy Bay and is emerging from under the retreating Guyot Glacier, about 149 miles (240 km) east-southeast of Cordova and 73 miles (118 km) northwest of Yakutat, Alaska. The peninsula was completely covered by the glacier when it was photographed in 1938, and by 1969 the tip of the peninsula was exposed.

In 1794,  Joseph Whidbey, with Vancouver’s expedition, explored the area but the bay was not shown on Vancouver’s charts. At that time the Guyot Glacier was joined with the Tyndall and Yahtse Glacier to form a massive ice front that reached the Gulf of Alaska and was thought to be the western lobe of the Malaspina Glacier. The glacial retreat began in 1899 and started to expose what is now Icy Bay. The glacier had a calving front that was over 6 miles (10 km) long. The glacier was also calving into deep water which led to a rapid retreat up to 1938. By 1969, the glacier had separated into three sections, and by 1986 the Guyot Glacier had retreated a considerable distance up a newly exposed fjord. Since 1904, the Guyot Glacier has retreated more than 31 miles (50 km).

Tidewater glaciers are glaciers that terminate in the ocean at either a grounded terminus or floating ice tongue. A temporal cycle for tidewater glaciers has been described as a slow advance over the course of centuries, until thinning near the terminus initiates a rapid retreat that completes within decades, stabilizing only when the glacier has retreated into shallow water. In general, the retreat phase of a tidewater glacier can be triggered by changes in climate, but once the retreat is initiated the glacier’s behavior is only weakly influenced by climate, and glacier geometry becomes a primary driver. Read more here and here. Explore more of Kashteen Peninsula here: