United States Geography

B12

a

Natural Features

The Coast Ranges and the Cascade Mountains dominate the terrain of the Pacific Northwest. These two north-south mountain systems run in ridges parallel to the Pacific Coast. Most of the population of the Pacific Northwest lives in the lowlands between these two mountain systems. Another major geographic feature of the Pacific Northwest is the Columbia River, one of the nation’s largest rivers. It cuts through a deep gorge in the Cascade Mountains along the border between Washington and Oregon before crossing lower-elevations of the coastal mountains to empty into the Pacific.

The Cascade Mountains extend almost due north and south across central Washington, Oregon, and northern California. The mountains lie about 160 to 240 km (about 100 to 150 mi) inland from the Pacific Coast. The higher elevations of the Cascades have a continuous snow cover. A number of east-west highways built through passes provide fairly easy travel through these mountains, except in winter, when they are periodically blocked by snow.

The Cascades include a series of volcanic peaks, including Mount Rainier, which rises (4,392 m/14,410 ft), Mount Adams (3,742 m/12,276 ft), and Mount Baker (3,285 m/10,778 ft) in Washington; Mount Hood (3,426 m/11,239 ft) in Oregon; and Mount Shasta at (4,317 m/14,162 ft) in California. Some of these volcanoes are still active, including Mount Saint Helens in Washington(2,550 m/8,365 ft), which erupted violently on May 18, 1980, blowing 400 m (1,300 ft) in elevation from the peak and sending a column of ash as high as 19 km (12 mi) high. In addition, the region experiences periodic mild earthquakes.

To the west of the Cascades lies a depression containing Oregon’s Willamette Valley and Washington’s Puget Sound. In the south end of the depression, the winding Willamette River drains Oregon’s central Willamette Valley before entering the Columbia River at Portland. The lowland depression continues north into Washington, where it submerges beneath Puget Sound, an inland extension of the Pacific Ocean lined with jagged peninsulas. The sound contains more than 300 islands, including the San Juan Islands. The Strait of Juan de Fuca provides shipping access to Puget Sound. The strait cuts west at the northern end of the sound and separates Canada’s Vancouver Island from Washington’s Olympic Peninsula.

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To the west, the Olympic Mountains on the Olympic Peninsula are the northernmost of the U.S. Coast Ranges. Because they rise from a dense coniferous forest that lies just above sea level, the Olympics are among the most visually impressive peaks in the United States. They reach a maximum elevation of 2,428 m (7,965 ft) at Mount Olympus. The Coast Ranges continue south through the Oregon Coast Range and the Klamath Mountains before continuing down through California and the Baja California peninsula in northwestern Mexico.

B12

b

Economy

The Pacific Northwest has a large but limited natural resource base, leading to an economy that is not highly diversified. The area’s abundant precipitation and temperate climate support dense, coniferous forests, which are the basis of the region’s dominance in the production of lumber, plywood, particleboard, pulp, and paper. Mountainous terrain and high levels of precipitation have provided this region with an enormous hydroelectric potential, focused on a system of dams and power-generating plants located on the Columbia and Snake rivers.

The mountainous terrain means that little land is suitable for agriculture, and dairy farming and grazing are the primary agrarian activities. Other agricultural activities include the growing of fruits, vegetables, grass seeds, mint, and hardier grain crops. The waters of the Pacific Northwest coast are ranked as one of the major fishing centers of the world. Salmon is the most important fish commercially, but the region has significant catches of herring, halibut, pollack, cod, and shellfish. Additional economic activities in the region include the aerospace industry, shipping, high-technology enterprises, shipbuilding, and the manufacture of wood products.

B12

c

Population

Regional population has remained relatively low, though two major urban centers have developed in the region. Portland, Oregon, is a dominant commercial center at the mouth of the Columbia River, and Seattle, Washington, is a large urbanized development on the shores of Puget Sound.

B

13

Alaska

The Alaska region includes the entire state of Alaska and encompasses approximately one-sixth of the total landmass of the United States, with about 1,600,000 sq km (about 615,000 sq mi) in area. The region is a sparsely populated area of vast wilderness and spectacular natural beauty, with varieties of animal life that are unique in the United States. Long winters, short summers, and large seasonal fluctuations in the length of days and nights characterize the harsh arctic climate that exists in much of this region. The exception is the narrow area that runs along the southeastern coast, where long, mild, wet winters and short, dry summers predominate.

B13

a

Natural Features

The topography of the region is extremely varied, with mountainous zones in southern and central Alaska, narrow coastal areas in the southwestern portion, and sweeping coastal plains to the north. The Alaska Range occupies south central Alaska, while the Wrangell Mountains skirt the southeastern Alaskan coastline along the border with Canada. The arctic portion of Alaska is composed largely of flat, featureless coastal plains bounded in part by the massive Brooks Mountain Range.

Conifer forests, often referred to as taiga, dominate Central Alaska, covering relatively flat terrain stretching hundreds of miles. Water, found in countless lakes and in extensive river basins such as the Yukon and Kuskokwim rivers, is abundant in the region.

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