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Activity 2.2 Hydrosphere/Cryosphere

  • Writer: Kamaria Flowers
    Kamaria Flowers
  • Feb 3
  • 3 min read
At Glacier Bay you can witness geologic processes and change usually barely noticed in the span of a human life. In 1680, there was no Glacier Bay, only a broad valley with a glacier moving down it. Abundant geologic information and Tlingit cultural memories describe a large valley in the lower Bay, environmentally harsh but habitable. Huna Tlingit villages bordered two named rivers flowing near present-day Rush Point and Bartlett Cove. Huna Tlingit place names speak eloquently of the bay and even reflect the landscape changes that occurred as the glacier advanced and later retreated.
At Glacier Bay you can witness geologic processes and change usually barely noticed in the span of a human life. In 1680, there was no Glacier Bay, only a broad valley with a glacier moving down it. Abundant geologic information and Tlingit cultural memories describe a large valley in the lower Bay, environmentally harsh but habitable. Huna Tlingit villages bordered two named rivers flowing near present-day Rush Point and Bartlett Cove. Huna Tlingit place names speak eloquently of the bay and even reflect the landscape changes that occurred as the glacier advanced and later retreated.
The Little Ice Age came and went quickly by geologic measures. By 1750 the glacier reached its maximum, overwhelming the Tlingit homeland and extending a snout into Icy Strait almost to Lemesurier Island. It was able to hold this position only briefly before succumbing to marine erosion and beginning the dramatic retreat for which Glacier Bay has become world famous. When Captain George Vancouver sailed here 45 years later, the glacier had melted/calved back five miles into Glacier Bay
The Little Ice Age came and went quickly by geologic measures. By 1750 the glacier reached its maximum, overwhelming the Tlingit homeland and extending a snout into Icy Strait almost to Lemesurier Island. It was able to hold this position only briefly before succumbing to marine erosion and beginning the dramatic retreat for which Glacier Bay has become world famous. When Captain George Vancouver sailed here 45 years later, the glacier had melted/calved back five miles into Glacier Bay
When conservationist John Muir traveled here in search of active glaciers in 1879, the glacier he sought had retreated 40 more miles up the bay since Vancouver's visit. A renowned author, Muir captured the popular imagination about Alaska, attracting tourists (and researchers) to Glacier Bay. Like most people today, they arrived by ship.
When conservationist John Muir traveled here in search of active glaciers in 1879, the glacier he sought had retreated 40 more miles up the bay since Vancouver's visit. A renowned author, Muir captured the popular imagination about Alaska, attracting tourists (and researchers) to Glacier Bay. Like most people today, they arrived by ship.
Today you must travel 65 miles up the bay to view tidewater glaciers - a far cry from the glacier's 1750 maximum. The large glacier that once filled the bay has divided into its smaller tributaries and in all but a few special cases, retreated from salt water. Although spectacular, remember that today's glaciers are mere remnants of what once was. Will they advance again, or will Glacier Bay someday be all bay and no glacier?
Today you must travel 65 miles up the bay to view tidewater glaciers - a far cry from the glacier's 1750 maximum. The large glacier that once filled the bay has divided into its smaller tributaries and in all but a few special cases, retreated from salt water. Although spectacular, remember that today's glaciers are mere remnants of what once was. Will they advance again, or will Glacier Bay someday be all bay and no glacier?

Until 10,000 years ago, sheet ice was known to have more nomadic characteristics for seven million years and during the ice age these sheets of ice would reach as far south as far as the Midwest of the United States. Glacier Bay was a product of the "Little Ice Age," geological glacial advance of the Northen region. By 1750 Glacial Bay reached its maximum extent, now the glacier has receded sixty-five miles inland. Now ninety-five percent of Alaska's glaciers are thinning. So, what is the cause of the receding glacier, what is happening that is causing such a significant change?

Glaciers are known to have a natural cycle that cause them to advance and retreat. Now due to mankind's technological advancements, fossil fuels are burned increasing the amount of CO2 in the air which causing a heat trapping affect warming the Earth's. The increased warmth of causes a disruption in the natural cycles of glacial patterns. Along with the increased CO2, climate change has become an issue that affects the glacial destruction. Alaska climate has experienced a five degree (3 Celsius) increase since 1949. Some other reason that are causing major impacts:

  • Coastal Erosion – Changes in sea ice leave coastal Arctic communities vulnerable to erosion from increasingly intense storms. Rates of erosion have measured over 59 feet (18 meters) per year, forcing some communities to relocate at great expense and with incalculable cultural loss.

  • Glacial Melt – Of the more than 100,000 glaciers in Alaska, 95 percent are currently thinning, stagnating, or retreating, impacting both land and ocean environments.

  • Loss of Permafrost – Permafrost is ground that remains frozen for two consecutive years and is vital to the Northern Alaska landscape. Increased thawing of permafrost releases stored greenhouse gases and causes erosion, landslides, and damage to infrastructure.

U.S. Department of the Interior. (2023, May 10). Glacier Bay’s glacial history. National Parks Service. https://www.nps.gov/glba/learn/nature/glacier-bay-s-glacial-history.htm


U.S. Department of the Interior. (2023a, April 27). Climate change. National Parks Service. https://www.nps.gov/glba/learn/nature/climate-change.htm


 
 
 

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