Upper Fremont Glacier | |
---|---|
Type | Mountain glacier |
Location | Fremont County, Wyoming, USA |
Coordinates | 43°07′52″N109°36′58″W / 43.13111°N 109.61611°W [1] |
Area | 690 acres (2.8 km2) (in 1990) |
Length | 1.35 mi (2.17 km) |
Thickness | 538 ft (164 m) (in 1998) |
Terminus | Moraines |
Status | Retreating |
Upper Fremont Glacier is in the Fitzpatrick Wilderness of Shoshone National Forest in the U.S. state of Wyoming. [2] This Wind River Range alpine glacier is associated with the largest grouping of glaciers in the U.S. Rocky Mountains and lies on the north slope of Fremont Peak, the third tallest mountain in Wyoming. Upper Fremont Glacier is at an average altitude of 13,450 ft (4,100 m) and is one of the highest altitude glaciers in the American Rockies. [3]
Ice core samples were taken from Upper Fremont Glacier in 1990-1991. These ice cores were analyzed for climatic changes as well as alterations of atmospheric chemicals. In 1998 an unbroken ice core sample of 538 ft (164 m) was taken from the glacier and subsequent analysis of the ice showed an abrupt change in the oxygen isotope ratio oxygen-18 to oxygen-16 in conjunction with what is widely regarded as the end of the Little Ice Age, a period of cooler global temperatures between the years 1550 and 1850. [3] A linkage was established with a similar ice core study which had been undertaken on the Quelccaya Ice Cap in Peru, which also demonstrated the same changes in the oxygen isotope ratio during the same period. The climatic implications from the ice cores taken from both sites support evidence of a sudden global climate change during the mid 19th century. [4]
Ice cores from the glacier also showed increased levels of Tritium (3H) and chlorine-36 around the year 1963, which coincides with the peak period of above ground nuclear testing. [3]
The same ice cores were also tested for mercury deposition from natural and human-induced activities. This is the first known instance in which ice cores have been used to determine mercury deposition from a mid-latitude glacier in North America, as all previous studies have been derived from other sources. [5] The majority of mercury deposition is by way of the atmosphere and sources of the element may be from volcanic activity or from industrialization, but volcanoes are believed to contribute a small proportion of the mercury. [5] The ice core samples from the Upper Fremont Glacier indicated that levels of mercury increased dramatically during the Industrial Revolution and have decreased significantly since the mid-1980s. It is believed that the decrease in mercury deposition since the 1980s coincides with the passage of the Clean Air Act. [5]
The Pleistocene is the geological epoch that lasted from c. 2.58 million to 11,700 years ago, spanning the Earth's most recent period of repeated glaciations. Before a change was finally confirmed in 2009 by the International Union of Geological Sciences, the cutoff of the Pleistocene and the preceding Pliocene was regarded as being 1.806 million years Before Present (BP). Publications from earlier years may use either definition of the period. The end of the Pleistocene corresponds with the end of the last glacial period and also with the end of the Paleolithic age used in archaeology. The name is a combination of Ancient Greek πλεῖστος (pleîstos) 'most' and καινός 'new'.
Belukha Mountain (; Russian: Белуха, IPA:[bʲɪˈɫuxəl], also known as Beluga Mountain, Icemount Peak, or The Three Peaks, is the highest peak of the Altai Mountains in Russia and the highest of the South Siberian Mountains system. It is part of the Golden Mountains of Altai World Heritage Site.
The Uinta Mountains are an east-west trending mountain range in northeastern Utah extending a short distance into northwest Colorado and slightly into southwestern Wyoming in the United States. As a subrange of the Rocky Mountains, they are unusual for being the highest range in the contiguous United States running east to west, and lie approximately 100 miles (160 km) east of Salt Lake City. The range has peaks ranging from 11,000 to 13,528 feet, with the highest point being Kings Peak, also the highest point in Utah. The Mirror Lake Highway crosses the western half of the Uintas on its way to Wyoming. Utah State Route 44 crosses the east end of the Uintas between Vernal and Manila.
In the study of past climates ("paleoclimatology"), climate proxies are preserved physical characteristics of the past that stand in for direct meteorological measurements and enable scientists to reconstruct the climatic conditions over a longer fraction of the Earth's history. Reliable global records of climate only began in the 1880s, and proxies provide the only means for scientists to determine climatic patterns before record-keeping began.
Fossil Mountain is located in the Teton Range, within the Jedediah Smith Wilderness of Caribou-Targhee National Forest, U.S. state of Wyoming.
The Byrd Polar and Climate Research Center (BPCRC) is a polar, alpine, and climate research center at Ohio State University founded in 1960.
The Medicine Bow Mountains are a mountain range in the Rocky Mountains that extend 100 miles (160 km) from northern Colorado into southern Wyoming. The northern extent of this range is the sub-range the Snowy Range. From the northern end of Colorado's Never Summer Mountains, the Medicine Bow mountains extend north from Cameron Pass along the border between Larimer and Jackson counties in Colorado and northward into south central Wyoming. In Wyoming, the range sits west of Laramie, in Albany and Carbon counties to the route of the Union Pacific Railroad and U.S. Interstate 80. The mountains often serve as a symbol for the city of Laramie. The range is home to Snowy Range Ski Area.
Cloud Peak is the highest peak within the Bighorn Mountains in the U.S. state of Wyoming.
Fremont Peak is the third highest peak in the state of Wyoming, surpassed only by Gannett Peak and Grand Teton, and straddles the boundary between Fremont and Sublette counties in the Wind River Range. It is named for American explorer John C. Frémont who climbed the peak with Charles Preuss and Johnny Janisse from August 13 to August 15, 1842. Kit Carson had been with the climbing party on its first attempt at the peak, but had gone back for supplies the day Fremont and his men reached the summit. Carson is thought by some to have been the first to climb neighboring Jackson Peak. At that time, Fremont Peak was mistakenly thought to be the highest mountain in the Rocky Mountains, although there are actually over 100 higher peaks in the Rocky Mountain range.
Shoshone National Forest is the first federally protected National Forest in the United States and covers nearly 2,500,000 acres (1,000,000 ha) in the state of Wyoming. Originally a part of the Yellowstone Timberland Reserve, the forest is managed by the United States Forest Service and was created by an act of Congress and signed into law by U.S. President Benjamin Harrison in 1891. Shoshone National Forest is one of the first nationally protected land areas anywhere. Native Americans have lived in the region for at least 10,000 years, and when the region was first explored by European adventurers, forestlands were occupied by several different tribes. Never heavily settled or exploited, the forest has retained most of its wildness. Shoshone National Forest is a part of the Greater Yellowstone Ecosystem, a nearly unbroken expanse of federally protected lands encompassing an estimated 20,000,000 acres (8,100,000 ha).
Mount Sacagawea is the eighth-highest peak in the U.S. state of Wyoming and the seventh-highest in the Wind River Range. It was named after Sacagawea, the young Lemhi Shoshone woman who accompanied the Lewis and Clark Expedition as an interpreter and guide. The Upper Fremont Glacier is located southeast and the Sacagawea Glacier is northeast of the mountain. Straddling the Continental Divide, Mount Sacagawea is one mile (1.6 km) northwest of Fremont Peak.
Heap Steep Glacier is located east of the Continental Divide in the northern Wind River Range in the US state of Wyoming. The glacier is situated in the Fitzpatrick Wilderness of Shoshone National Forest, and is among the largest grouping of glaciers in the American Rocky Mountains. Heap Steep Glacier is in a north facing cirque, below the summit of Sunbeam Peak. A large terminal moraine and small proglacial lake are located below the glacier.
Lower Fremont Glacier is east of the Continental Divide in the northern Wind River Range in the U.S. state of Wyoming. The glacier is in the Fitzpatrick Wilderness of Shoshone National Forest, and is among the largest grouping of glaciers in the American Rocky Mountains. Lower Fremont Glacier flows to the southeast and the rapid retreat of this glacier has left behind lateral moraines and a proglacial lake. Lower Fremont Glacier is separated from the Bull Lake Glacier by a moraine and from the Upper Fremont Glacier by cliffs.
Bull Lake Glacier is located immediately east of the Continental Divide in the northern Wind River Range in the U.S. state of Wyoming. The glacier is in the Fitzpatrick Wilderness of Shoshone National Forest, and is among the largest grouping of glaciers in the American Rocky Mountains. Bull Lake Glacier flows to the east and starts below the summit of Jackson Peak. It is adjacent to Lower Fremont Glacier though the two are separated by a moraine.
Knife Point Glacier is on the east side Continental Divide in the northern Wind River Range in the U.S. state of Wyoming. The glacier is in the Fitzpatrick Wilderness of Shoshone National Forest, and is among the largest grouping of glaciers in the American Rocky Mountains. Knife Point Glacier flows to the north and starts below the summit of Knife Point Mountain.
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Sowers Glacier is a glacier that flows from the prominent cirque on the east side of Craddock Massif and continues between Willis Ridge on the north, and Sanchez Peak and Stolnik Peak on the south, to join Thomas Glacier north of Mount Osborne, in the Sentinel Range, Ellsworth Mountains in Antarctica.