Brooks Range, Alaska

Brooks Range, Alaska

 

Brooks Range, Alaska

The mighty Brooks Range marks a 700-mile-long continental drainage divide in North America's far northern reaches. Here, rivers running north empty into the Arctic Ocean, while those running south flow into the Yukon River. This remote massif is estimated to be 126 million years old and contains a rich fossil record of the ancient seabed it once was. Found among the tundra and stands of spruce trees are fossilized corals from the Cambrian period. The mountains also teem with living wildlife, with a portion of the range lying within the Arctic National Wildlife Refuge.

 

 

The Brooks Range (Gwich'in: Gwazhał) is a mountain range in far northern North America stretching some 700 miles (1,100 km) from west to east across northern Alaska into Canada's Yukon Territory. Reaching a peak elevation of 8,976 feet (2,736 m) on Mount Isto, the range is believed to be approximately 126 million years old.

In the United States, these mountains are considered a subrange of the Rocky Mountains, whereas in Canada they are considered separate, as the northern border of the Rocky Mountains is considered to be the Liard River far to the south in the province of British Columbia.

 

While the range is mostly uninhabited, the Dalton Highway and Trans-Alaska Pipeline System run through the Atigun Pass (1,415 m, 4,643 ft) on their way to the oil fields at Prudhoe Bay on Alaska's North Slope.

 

The Alaska Native villages of Anaktuvuk and Arctic Village, as well as the very small communities of Coldfoot, Wiseman, Bettles, and Chandalar, are the range's only settlements. In the far west, near the Wulik River in the De Long Mountains is the Red Dog mine, the largest zinc mine in the world.

 

The range was named by the United States Board on Geographic Names in 1925 after Alfred Hulse Brooks, chief USGS geologist for Alaska from 1903 to 1924.

Various historical records also referred to the range as the Arctic Mountains, Hooper Mountains, Meade Mountains and Meade River Mountains. The Canadian portion of the range is officially called the British Mountains. Ivvavik National Park is located in Canada's British Mountains.

 

Peaks

Brooks Range Mountains

Limestack Mountain, in the central Brooks Range

Limestack_Mountain._Gates_of_the_Arctic_National_Park,_Brooks_Range,_Alaska

Evening light turns the North face of Limestack Mountain into striped gold.

 

• Mount Isto 8,975.1 ft (2,735.6 m)
• Mount Hubley 8,914 ft (2,717 m)
• Mount Chamberlin 8,898.6 ft (2,712.3 m)
• Mount Michelson at 8,855 ft (2,699 m)
• The Gates of Kiev at 7,775 ft (2,370 m), the highest point in the central part of the range
• Black Mountain at 5,020 ft (1,530 m), the highest point in the far western part of the range.
• Mount Doonerak 7,457 ft (2,273 m)
• Mount Igikpak 8,276 ft (2,523 m)
• Frigid Crags West Gate 5,501 ft (1,677 m)
• Boreal Mountain East Gate 6,654 ft (2,028 m)
• Limestack Mountain 6,250 ft (1,900 m)
• Cockedhat Mountain 7,410 ft (2,260 m)

History

Bob Marshall explored the North Fork Koyukuk River area of the range in 1929. He named Mount Doonerak, explaining "the name Doonerak I took from an Eskimo word which means a spirit or, as they would translate it, a devil." Marshall described the mountain as, a "towering, black, unscalable-looking giant, the highest peak in this section of the Brooks Range."

 

Ecology

Area of the Arctic National Wildlife Refuge coastal plain, looking south toward the Brooks Range

 

The Brooks Range forms the northernmost drainage divide in North America, separating streams flowing into the Arctic Ocean and the North Pacific. The range roughly delineates the summer position of the Arctic front. It represents the northern extent of the tree line, with little beyond isolated balsam poplar stands occurring north of the continental drainage divide. Trembling aspen and white spruce also occur north of the Brooks Range, though they are limited to sites that have been disturbed by human activity. Southern slopes have some cover of black spruce, Picea mariana, marking the northern limit of those trees.  As the global mean temperature increases, tree line has been observed to move further north, changing the boundaries of where these trees are found.  An increase in shrub abundance is also being experienced in areas which were previously dominated by tundra, impacting the ecology of the area.

 

As one of the most remote and least-disturbed wildernesses of North America, the mountains are home to Dall sheep, grizzly bears, black bear, gray wolf, moose and porcupine caribou.

 

 

In Alaska, the Western Arctic Caribou herd (490,000 strong in 2004) traverses the Brooks Range in its annual migration. The smaller Central Arctic herd (32,000 in 2002), as well as the 123,000 animal Porcupine Caribou herd, likewise migrate through the Brooks range on their annual journeys in and out of the Arctic National Wildlife Refuge. The migration path of the Porcupine Caribou herd is the longest of any terrestrial mammal on earth.

 

The Porcupine caribou (Rangifer tarandus arcticus) is a herd or ecotype of barren-ground caribou, the subspecies of the reindeer or caribou found in Alaska, United States, and Yukon and the Northwest Territories, Canada.

 

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Meaghan Brackenbury · CBC News · Posted: Jan 13, 2023 6:56 PM EST | Last Updated: January 14, 2023

This undated file photo provided by the U.S. Fish and Wildlife Service shows caribou from the Porcupine Caribou Herd migrating onto the coastal plain of the Arctic National Wildlife Refuge in northeast Alaska. The herd is the focus of an upcoming summit in Fort McPherson, N.W.T. (U.S. Fish and Wildlife Service via The Associated Press)

 

Alaska Range

The Alaska Range stretches 650 miles from the Aleutian Peninsula to the Yukon Territory. Its tallest peak is Denali at 20,310 feet (6,190 meters), which is also the highest point on the North American continent. Formed primarily by tectonic activity, these mountains are characterized by dramatic elevations and rugged terrain. The range is known for its glacier systems, including the Kahiltna Glacier, the longest in the Alaska Range.

 

Coast Mountains

Hugging the Pacific Coast from Alaska to British Columbia, the Coast Mountains showcase glaciers, fjords, and stunning coastal vistas. Mount Logan, Canada’s highest peak towering at 19,551 feet, is a remarkable feature of this range, contributing to its rugged charm and remote allure.