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Research about Glacier National Park

Source-linked reports with geographic coverage including Glacier National Park.

79 records · Page 5Linked to original sources
USGS1980

Grinnell and Sperry Glaciers, Glacier National Park, Montana: A record of vanishing ice

Grinnell and Sperry Glaciers, in Glacier National Park, Mont., have both shrunk considerably since their discovery in 1887 and 1895, respectively. This shrinkage, a reflection of climatic conditions, is evident when photographs taken at the time of discovery are compared with later photographs. Annual precipitation and terminus-recession measurements, together with detailed systematic topographic mapping since 1900, clearly record the changes in the character and size of these glaciers. Grinnell Glacier decreased in area from 530 acres in 1900 to 315 acres in 1960 and to 298 acres in 1966. Between 1937 and 1969 the terminus receded nearly 1,200 feet. Periodic profile measurements indicate that in 1969 the surface over the main part of the glacier was 25-30 feet lower than in 1950. Observations from 1947 to 1969 indicate annual northeastward movement ranging from 32 to 52 feet and generally averaging 35-45 feet. The annual runoff at the glacier is estimated to be 150 inches, of which approximately 6 inches represents reduction in glacier volume. The average annual runoff at a gaging station on Grinnell Creek 1.5 miles downvalley from the glacier for the 20-year period, 1949-69, was 100 inches. The average annual precipitation over the glacier was probably 120-150 inches. Sperry Glacier occupied 800 acres in 1901; by 1960 it covered only 287 acres, much of its upper part having disappeared from the enclosing cirque. From 1938 to 1969 certain segments of the terminus receded more than 1,000 feet. Profile measurements dating from 1949 indicate a lowering of the glacier surface below an altitude of 7,500 feet, but a fairly constant or slightly increased elevation of the surface above an altitude of 7,500 feet. Along one segment of the 1969 terminus the ice had been more than 100 feet thick in 1950. According to observations during 1949-69, average annual downslope movement was less than 15 feet per year in the central part of the glacier and slightly more rapid toward the edges and at higher parts on the glacier.

Montana↗
USGS1973

Evaluation of the ground-water supply at eight sites in Glacier National Park, northwestern Montana

Seven of eight test holes drilled in Glacier National Park derive water from the Quaternary alluvial or glacial deposits. The eighth test hole was dry. Aquifer tests indicated that production wells at the seven sites will yield enough water for domestic or campground uses. Estimated maximum pumping rates range from 4 to 50 gallons per minute (0.2 or 3.2 liters per second). The water is of excellent chemical quality and generally the major dissolved constituents are calcium and bicarbonate.

Montana↗
USGS1962

Glacier observations, Glacier National Park, Montana, 1961

This report records the results obtained during the 1961 season in the continuing program of glacier observations in Glacier National Park. The investigations currently in progress relate to the Grinnell and Sperry Glaciers. This program is carried on cooperatively by the Geological Survey, the National Park Service and the Weather Bureau. The program includes the determination of annual changes in the surface elevation of the glaciers by the measurement of profiles, and changes during the summer months by the establishment of and observations at ablation stakes; rapping the glacier termini in selected years to record advance or recession; determination of annual movement by the location of marked rocks; the operation of two storage-precipitation gages in the immediate vicinity of the Grinnell Glacier to record annual precipitation; the operation of two gaging stations, one just below the Grinnell Glacier during the summer months and one Just below the outlet of Grinnell Lake on a year round basis; temperature data near the Grinnell Glacier and temperature and precipitation data at the Sperry Chalet near the Sperry Glacier during the summer months. The results of the work are described in the following sections.

Montana↗
USGS1914

Glaciers of Glacier National Park

Glacier National Park derives its name and much of its interest from the presence of many small glaciers. Very much of the grandeur of its wonderful Alpine scenery, the final sculpturing of the great mountain valleys and of the amphitheaters at their heads, and the production of the basins of its many beautiful lakes are due to the action of the more extended glaciers of the past. There are in the park about 90 small glaciers ranging in size from Blackfeet Glacier, with its 3 square miles of ice, down to masses but a few acres in extent yet exhibiting the characteristics of true glaciers. The most easily accessible of these from the beaten trails are the Blackfeet and Sperry Glaciers and the small glaciers at Iceberg Lake and at Ahern Pass. Some of the others can be reached by tourists who are willing to undergo the exertions of mountain climbing. Among these are Grinnell, Chaney, Shepard, Vulture, and Carter Glaciers, and one or two at Brown Pass. (See map facing page 17.) After examining these features one can easily picture to himself, as he looks down the valleys, the great rivers of ice which in ages past cascaded from the cliffs below the upper cirques, converged as tributaries from the many branch valleys, and united in great trunk glaciers. In imagination lie can see these great glaciers many hundreds of feet ill depth filling the great mountain volleys from side to side, and deploying thence upon the bordering plains. lie seems to see these mighty engines plucking away the rock ribs of the mountains, smoothing, grinding, and polishing the irregularities and sweeping away the debris to be spread on the plains below. These glaciers developed and extended three times and, after each development, the congealed masses melted away on the return of milder climatic conditions, until at length only the small cliff glaciers of the present day are left lurking in the protected recesses at the heads of the capacious valleys. Many of the rock-walled amphitheaters are no longer occupied by ice, but from all there issue streams fed by the melting snow or ice. These plunge over the cliffs in beautiful foaming cascades and rush on down the mountain gorges. The melting glaciers left many inclosed basins large and small, and in these the waters rest a while and mirror in their crystal depths the dark green of the surrounding forests, the rich colors of the rugged mountain walls, and the deep blue of the cloud-flecked sky. On again from lake to lake the waters flow and finally start down their long courses to the sea to merge at length with the chill waters of Hudson Bay, the balm t ides of the Gulf of Mexico, or the rolling billows of the Pacific. Compared in size with the great glaciers of Alaska the glaciers of Glacier National Park are insignificant. They are even surpassed in size by those of the Alps, of the Canadian Rockies, and of Mount Rainier, Washington. They are, however, thought small, among the best examples of this interesting type of phenomena now existing in the United States. They have also a splendid setting in magnificent Alpine scenery, unsurpassed in grandeur anywhere. Hidden away in the recesses of the mighty mountain ranges these rare and wonderful features form a climax to many of the interesting trips open to the tourist.

Montana↗