Margerie Glacier is a 21-mile-long (34 km) tide water glacier in Glacier Bay in Alaska
and is part of the Glacier Bay National Park
and Preserve. It begins on the south slope of Mount Root, at the Alaska-Canada
border in the Fairweather Range
, and flows southeast and northeast to Tarr Inlet. It was named for the famed French geographer and geologist Emmanuel de Margerie (1862-1953), who visited the Glacier Bay in 1913.
It is an integral part of the Glacier Bay, which was declared a National Monument on February 26, 1925, a National Park and Wild Life Preserve on December 2, 1980, a UNESCO declared World
Biosphere Reserve in 1986 and a World Heritage Site in 1992. While most of the tidewater and terrestrial glaciers in the Park are stated to be thinning and receding over the last several decades, Margerie Glacier is said to be stable and Johns Hopkins Glacier
is stated to be advancing, on the eastern face of the Fairweather Range.
Margerie Glacier, categorized as a typical example of tide-water glacier (tidewater glacier is defined as a glacier which generates sufficient snow to flow out from the mountains to the sea.), has a total height of 350 feet (110 m), out of which 250 feet (76 m) raises above the water level and 100 feet (30 m) is beneath the water surface. (This height is stated to be larger than the 307 feet (94 m) high Statue of Liberty). The glacier exhibits a distinctive curved layer of rock debris mixed with ice.
The glacier has impressive configurations (as if carved with hand tools), in a "jagged and twisted form", set in ice which is seen in blue color as a result of absorption of rays of shorter red and green wavelengths. It is a much cleaner glacier as compared to other glaciers in the Glacier Bay. It is also one of the most active glacier for "Calving" (a word meaning breaking and dropping of ice walls into the sea). As the glacier calves, "a rifle-like crack and a booming roar is heard creating a boiling like turbulence." Some times, ice caves get formed in the glacier, which is considered highly unstable since blocks of ice collapse into the water from the sides of the cave formation and create a resounding noise as it splashes.
The glaciers in the Glacier Bay are stated to be remnants of a general "ice advance - the Little Ice Age - that began about 4,000 years ago". This advance is not comparable to continental glaciation that occurred during "Pleistocene times known as the Wisconsin Ice Age". However, about 1750, the 'Little Ice Age' reached its maximum stage and then melting started. Ice flows have been recorded at Margerie Glacier 2,000 feet (610 m) per year or 6 feet (1.8 m) per day. Its advance was reported to be at the rate of 30 feet (9.1 m) per year till 1998 when some degree of recession has been noticed at its northern terminus "forming a small embayment," while the southern part is advancing at 1 foot (0.30 m) per year.
In the 1990s, the glacier was attached to the Grand Pacific Glacier. However, it is now detached from the Grand Pacific (which is said to be receding) and moranic material is seen where it has separated on its northern extremity, discerned by a small stream. As result, the Margerie Glacier is termed "a hanging glacier with its base about 600 feet (180 m) above the floor of Tarr Inlet near its center." Fresh water 'upswellings' are seen to emerge from the Central
area of the glacier, generated by the melt water discharges of sub glacial streams; such areas are swarmed by sea birds for feeding on fish.
Flora and Fauna
Margerie Glacier is a part of the Glacier Bay National Park and Preserve, which is a myriad combination tidewater glaciers, snow-capped mountain ranges, ocean coastlines, deep fjords, and freshwater rivers and lakes, provides widely varying land and seascape “hosts a mosaic of plant communities and a variety of marine and terrestrial wildlife.” Arctic terns and gulls nest in the rocks of the Margerie Glacier. As this glacier calves, it disturbs the krill and small fish, thus making it an ideal spot for birds. Whales and bears are also seen around this glacier.