Английская Википедия:Grand Pacific Glacier

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Шаблон:About Шаблон:One source Шаблон:Infobox glacier

Grand Pacific Glacier is a Шаблон:Convert long glacier in British Columbia and Alaska. It begins in Glacier Bay National Park in the St. Elias Mountains, Шаблон:Convert southwest of Mount Hay, trends east into the Grand Pacific Pass area of British Columbia, and then southeast to the head of Tarr Inlet at Alaska-Canada boundary, 68 miles (109 km) west of Skagway.[1]

National Park Service Information

In 2004 Grand Pacific Glacier was about Шаблон:Convert wide at the terminus, averaging about Шаблон:Convert high at the ice face, up to Шаблон:Convert deep at the waterline and over Шаблон:Convert long. Much of the ice margin was then grounded at low tide; the calving section probably reached a water depth of only Шаблон:Convert. The ice cliff was estimated to be Шаблон:Convert high where it was grounded, but about Шаблон:Convert and up to Шаблон:Convert high where it calved into Tarr Inlet. Behind the terminus, the ice may thicken to Шаблон:Convert or more. The western two thirds of the ice in the terminus of the Grand Pacific Glacier originate from the tributary Ferris Glacier, and flowed about Шаблон:Convert per year or about Шаблон:Convert per day. This latter estimate was based on measurements of aerial photographs taken between 1988 and 1990 and may be higher than 2004 rates based on the fact that the ice had been thinning over the last 7 years or so. The eastern portion of Grand Pacific Glacier moved only about Шаблон:Convert per year based on GPS measurements made by the Cold Regions Research and Engineering Laboratory (CRREL) in 1998–1999. It had advanced at a rate of about Шаблон:Convert per year for the last several decades, but it reached a maximum position when it joined Margerie Glacier around 1992. In 2004 those glaciers were no longer together due to recession of the Grand Pacific margin. A small stream flowed between the two termini. The eastern edge was then receding at about Шаблон:Convert per year and showed significant thinning and closure of crevasses. In about 1996, an embayment began to form in the center of Grand Pacific's terminus. Since then, the center of the ice cliff began to calve more rapidly and was slowly receding at perhaps Шаблон:Convert or less per year. In 2004 the CRREL anticipated that retreat would accelerate as the embayment enlarged and the depth at the waterline increased. In such a scenario, retreat was likely to continue until the terminus reaches a position where it will become grounded above mean tide. The grounded western edge of the glacier was also slowing receding and thinning. Rock debris from landslides and medial moraines cover much of this side of the glacier and extends across almost two-thirds of the ice face. Where this rock debris is more than an inch thick, it insulates the ice, slows melting and results in a thicker ice mass than where the ice is clean. In many areas on the glacier, the debris is more than Шаблон:Convert thick.[2]

See also

References

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