North Cascades
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Mount Shuksan, one of the most dramatic peaks of the North Cascades

Mount Despair, located within North Cascades National Park

The North Cascades are a section of the Cascade Range of western North America. They span the border between the Canadian province of British Columbia and the US state of Washington. They are predominantly non-volcanic, but include the stratovolcanoes Mount Baker and Glacier Peak, which are part of the Cascade Volcanic Arc. The portion in Canada is known as the Canadian Cascades, a designation that also includes the mountains above the east bank of the Fraser Canyon as far north as the town of Lytton, at the confluence of the Thompson and Fraser Rivers. The northeastern boundary of the range, which is officially designated in Canada as the Cascade Mountains, ¹ departs the Thompson via the Nicoamen River and runs via Lawless Creek, the Tulameen River and Copper Creek to the Similkamen River.

The North Cascades are most notable for their dramatic scenery and challenging mountaineering, both resulting from their steep, rugged topography. While all of the peaks but the two volcanos are under 10,000 feet (3,048 m) in elevation, the low valleys provide great local relief, often over 6,000 feet (1,830 m).

Geography

The large amount of precipitation, much of it in the form of snow, and the resulting glaciation, combine with the regional uplift to create a dramatic landscape. Deep, U-shaped valleys carved by glaciers in Pleistocene time separate sharp ridges and peaks carved into steep shapes by more recent snow and ice.

Extent

The Fraser River and Similkameen River in British Columbia form the northern boundary of the North Cascades. On the east, the Okanogan River and the Columbia River bound the range. On the west, the foothills of the range are separated by a narrow coastal plain from Puget Sound.

The southern boundary of the North Cascades is less definite. For the purposes of this article, it will be taken as US Highway 2, running over Stevens Pass, or equivalently, the Skykomish River, Nason Creek, and the lower Wenatchee River. This roughly follows Beckey's division. (Beckey 1987:17) Sometimes the southern boundary is defined by Snoqualmie Pass and the approximate route of Interstate 90.²

Climate

The climate in the North Cascades varies considerably by location and elevation. The western slope of the range is wet and cool, with 60 to 250 inches (1.5 to 6.25 metres) of precipitation per year. This produces a temperate rain forest climate in the low valleys, which then grades into montane and alpine climates on mountain slopes and peaks. Summers are comparatively dry, with far less precipitation than in winter. The eastern slope lies in the rain shadow of the range, since prevailing winds and most moisture come from the west, and hence is significantly drier than the western side of the main divide, becoming semi-arid in the eastern lowlands. (Mathews 1988:557-562, Beckey 1996:12) As with most mountain areas, precipitation increases dramatically with increasing elevation. As a result, there is a great deal of winter snow and glaciation in the high North Cascades.

Glaciers

Crossing a crevasse in the Easton Glacier on Mount Baker

While alpine glaciers are a defining feature of the Cascade Range as a whole, this is especially true of the North Cascades. The stratovolcanoes (Mount Baker and Glacier Peak) are the most obviously glaciated peaks and have the largest glaciers, but many of the smaller, nonvolcanic peaks are glaciated as well. For example, the portion of the Cascades north of Snoqualmie Pass (roughly the North Cascades as defined in this article) These glaciers all retreated from 1900-1950. From 1950-1975 many but not all North Cascades advanced. Since 1975 retreat has become more rapid with all 107 glaciers monitored retreating by 1992. There are approximately 700 glaciers in the range, though some have already disappeared (Pelto, North Cascade Glacier Climate Proejct). Since a brief advancing period in the 1950s, most of these glaciers have been retreating. This is a serious concern to water managers in the region, as the glaciers (and the winter snowpack) form a large reservoir of water. As snow and ice melts in the summer, the resulting meltwater compensates for the seasonal decrease in precipitation. As glaciers retreat they will provide less summer runoff.

Geology

The bulk of the North Cascades consists of "deformed and metamorphosed, structurally complex pre-Tertiary rocks" (Beckey 1987:17). These originated in diverse locations around the globe: the area is built of several ("perhaps ten or more") different terranes of different ages and origins. (Beckey 1996: 10) In addition, oceanic crust from the Pacific Ocean is being subducted under the continental margin, which forms the current volcanoes as well as a number of "dioritic, gabbroic, or other dark intrusions." (Mathews 1988:519-520) The current uplift began around 8 million years ago. (Mathews 1988:522)

History

Big log in the North Cascades, 1937

On the United States side of the border, early inhabitants of the North Cascades included the Nooksack, Skagit, and Sauk-Suiattle tribes on the west, and the Okanagan people on the eastern side, with the Nlaka'pamux people of what is now Canada claiming hunting territory in the heart of the range. The tribes living and using the range on the Canadian side of the border are the Nlaka'pamux, Sto:lo and the Upper and Lower Similkameen subgroups of the Okanagan (a now-extinct group known as the Nicola Athapaskans also inhabited and hunted in the area now occupied by the Simlikameen). Many current geographic names in the region are derived from native terms, either by transliteration or translation. Beckey notes that "Many names were derived from Chinook jargon, mostly applied by the Forest Service from 1910 to 1940...." (Beckey 1996:141)

Fur traders entered the area in the first half of the nineteenth century, coming from Canada and from Astoria on the Columbia River. One of the earliest was Alexander Ross, of the Pacific Fur Company, who crossed the range in the summer of 1914. (Beckey 1996:203) The period of uncertainty surrounding the disputed Oregon Country gave way in the second half of the century to a period of tentative US Army exploration in tandem with violent subjugation of Indian tribes, reconnaissance for possible railroad routes (none of which were viable north of the one eventually put in over Stevens Pass, at the southern edge of the North Cascades) and various mining rushes.

Miners dominated the exploration and development of the range from the 1880s through the early twentieth century. For example, mines around the boomtown of Monte Cristo, in the southwest portion of the North Cascades, produced "between $1 and $2.7 million in silver and gold" (Beckey 1996:27). The Holden Mine, on the east side of the main divide, produced 106,000 tons of copper and 600,000 ounces of gold. (Beckey 1996:140)

Early settlers also arrived in the foothills of the North Cascades in the latter half of the 1800s, and utilized the range in a limited way as a source of timber and grazing land. However the range is so rugged that this exploitation was less dramatic than in other more gentle landscapes.

Early recreational use of the range included expeditions by the local climbing clubs, The Mountaineers and The Mazamas. However even these groups did not fully explore the inner reaches of the range and ascend the most difficult peaks until the 1930s and 1940s.

Protected areas

Diablo Lake, Colonial Peak and Pyramid Peak, in the North Cascades

The North Cascades include various protected areas. Chief among the areas in Washington is North Cascades National Park, occupying much of the area between Mount Baker and the Cascade divide. Contiguous with the Park are Ross Lake National Recreation Area and Lake Chelan National Recreation Area. Designated wilderness areas in the range include:

• Mount Baker Wilderness
• Glacier Peak Wilderness
• Boulder River Wilderness
• Henry M. Jackson Wilderness,
• Lake Chelan-Sawtooth Wilderness
• Noisy-Diobsud Wilderness
• Pasayten Wilderness

In British Columbia, protected areas include

• Skagit Valley Provincial Park
• E.C. Manning Provincial Park
• Cascade Recreation Area
• Cathedral Provincial Park
• Coquihalla Canyon Provincial Park

Notable peaks

The following North Cascades peaks are notable for their height (absolute elevation):

(The above table uses a topographic prominence cutoff of 1000 feet, in order to list only highly independent peaks.)

The following peaks are notable for their topographic prominence:

Jack Mountain

The following peaks are notable for their large, steep rise above local terrain. Peaks are listed in descending order by elevation.

See also

• Cascades
• Ptarmigan Traverse
• Methow, Washington

References

Sources

• Fred Beckey, Cascade Alpine Guide, Volume 1 (Second Edition), The Mountaineers, 1987.
• Mauri Pelto, North Cascade Glacier Climate Project- glacier retreat http://www.nichols.edu/departments/glacier/Bill.htm
• Mauri Pelto, North Cascade Glacier Climate Project-Death of a Glacier

http://www.nichols.edu/departments/glacier/deathglacier.htm

• Fred Beckey, Cascade Alpine Guide, Volume 2 (Second Edition), The Mountaineers, 1996.
• Fred Beckey, Cascade Alpine Guide, Volume 3 (Second Edition), The Mountaineers, 1995.
• Daniel Mathews, Cascade Olympic Natural History: A Trailside Reference, Raven Editions, 1988.
• The Northwest Peakbagger's Asylum

External links

• North Cascades National Park/Ross Lake and Lake Chelan National Recreation Areas: Official Site
• More information on high-prominence peaks
• More information on peaks with large, steep local relief
• NorthCascadesmaps.com Interactive North Cascades Map Server