SPERRY GLACIER, GLACIER NATIONAL PARK, MONTANA
September 4, 2006
The glacier's surface area was 3.09 sq. km in 1850. The area in 1993, the date of the last precise survey, was 1.06 sq.km. In 1850, Glacier National Park had 150 glaciers. In 1968, global warming had reduced that number to just over 50. By 1998, the park had 27 glaciers; that number remains the official count as of this writing, but by next year three more will have been taken off the list. Each of the glaciers is shrinking at the rate of 3 to 8% of its surface area per year. The shrinkage is due to an increase in average annual temperatures and/or a reduction of snowfall. If the present rate of increased temperatures continues, the park will be glacier-less by 2030; if the climate gets no warmer, but stays at current temperatures, the glaciers will be gone by 2100.
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