Pacific Coast of North America

Pacific Coast of North America
Name	Pacific Coast of North America
Subdivision type	Countries
Subdivision name	Canada, United States, Mexico

Contents

Pacific Coast of North America is the western shoreline stretching from the Bering Strait and Alaska southward through British Columbia, the U.S. state of Washington, Oregon, California, and the Baja California Peninsula of Mexico. This maritime corridor links major features such as the Gulf of Alaska, the California Current, the Gulf of California, and the Pacific Plate margin while adjoining cultural regions including the Pacific Northwest, California, and Baja California.

Geography and Boundaries

The coast extends from the Bering Strait adjacent to Chukchi Sea and Arctic Ocean limits past the Aleutian Islands arc, tracing the continental margin along the Alaska Peninsula into the Inside Passage of British Columbia near Vancouver Island, across the Strait of Juan de Fuca to the Salish Sea, down the Olympic Peninsula, the Willamette Valley corridor to Cape Blanco, proceeding by prominent capes like Cape Mendocino, Point Reyes, Monterey Bay, and Point Conception, then through the Los Angeles Basin, past San Diego, across the international frontier to Ensenada, along the western edge of the Baja California Peninsula and into the Gulf of California adjacent to Sonora and Sinaloa. Political boundaries intersect the coasts of Alaska, Yukon maritime zones, British Columbia, Washington (state), Oregon (state), California (state), and Baja California (state), involving maritime jurisdictions clarified by instruments such as the United Nations Convention on the Law of the Sea and bilateral accords like the Boundary Treaty of 1846.

The margin is dominated by interactions among the Pacific Plate, the North American Plate, the Juan de Fuca Plate, the Explorer Plate, and the Cocos Plate, producing subduction zones, transform faults such as the San Andreas Fault, and accretionary prisms along the Cascadia Subduction Zone and the Alaskan Megathrust. Terranes accreted during Mesozoic episodes include elements now recognized in the Insular Belt, the Coast Mountains, and the Sierra Nevada. Volcanism from the Aleutian Arc through the Cascade Range to the Trans-Mexican Volcanic Belt shapes iconic peaks like Mount St. Helens, Mount Rainier, Mount Shasta, and Popocatépetl influence sediment supply to coastal shelves such as the Continental Shelf. Seismic hazards have produced events like the 1964 Alaska earthquake and concerns over a future Cascadia earthquake, while basin evolution created features such as the Salton Trough and the Los Angeles Basin.

Oceanic forcing from the North Pacific Gyre, the California Current, and the Alaska Current governs coastal SSTs and upwelling regimes near headlands like Point Arena and bays such as San Francisco Bay and Monterey Bay. Atmospheric patterns including the Pacific Decadal Oscillation, the El Niño–Southern Oscillation, the North Pacific High, and the Aleutian Low modulate precipitation across rainforests of the Hoh River watershed, Mediterranean climates of the Central Valley margin, and arid zones of the Sonoran Desert. Tidal regimes in estuaries like Puget Sound, San Francisco Bay, and the Gulf of California interact with riverine inputs from the Columbia River, the Sacramento River, the Eel River, and the Baja California coastal drainages to influence sediment transport, hypoxia events, and coastal upwelling productivity documented near the Monterey Submarine Canyon.

Temperate rainforests of the Tongass National Forest and Great Bear Rainforest host species like the grizzly bear, black bear, salmon runs of sockeye salmon, and killer whales, while kelp forests off Channel Islands National Park and rocky intertidal zones support invertebrates such as the sea star formerly impacted by sea star wasting disease and macroalgae like Macrocystis pyrifera. Coastal chaparral and oak woodlands near Santa Monica Mountains and Anza-Borrego Desert State Park harbor endemic flora including Joshua Tree relatives and faunal assemblages like the California condor. Estuaries including Elkhorn Slough, Tijuana River Estuary, and San Francisco Estuary sustain migratory birds on routes such as the Pacific Flyway and support endangered taxa under protections like the Endangered Species Act. Offshore, deep-sea habitats along the Juan de Fuca Ridge, the Gulf of California Rift Zone, and abyssal plains shelter hydrothermal vent communities studied by institutions such as the Monterey Bay Aquarium Research Institute.

Indigenous nations including the Haida, Tlingit, Tsimshian, Coast Salish, Lummi, Nuu-chah-nulth, Yurok, Hupa, Pomo, Ohlone, Chumash, Tongva, Kumeyaay, Maya-related groups in northwestern Mexico and numerous others established maritime cultures with canoe traditions, potlatch systems, and salmon fisheries later disrupted by colonization by Spanish Empire explorers like Juan Rodríguez Cabrillo, Russian colonization at Sitka, and colonial ventures by the Hudson's Bay Company and the Spanish missions in California. Later developments include the California Gold Rush, the construction of the Transcontinental Railroad connections, the growth of port cities such as Vancouver (city), Seattle, Portland, Oregon, San Francisco, Los Angeles, and Ensenada, and cultural movements like the Beat Generation and Silicon Valley innovation concentrated near San Jose, California and San Francisco Bay Area hubs.

Major seaports along the coast include Port of Vancouver (British Columbia), Port of Seattle, Port of Tacoma, Port of Portland (Oregon), Port of San Francisco, Port of Long Beach, Port of Los Angeles, Port of San Diego, and Port of Ensenada, forming trade links with Panama Canal routes, transpacific shipping to East Asia hubs like Shanghai, Yokohama, Busan, and Hong Kong. Coastal fisheries historically exploited Pacific halibut, Dungeness crab, and sardine fisheries and support aquaculture such as salmon farming near Prince William Sound and Baja California. Energy infrastructure includes offshore platforms in the Santa Barbara Channel, LNG terminals serving trade with Japan and South Korea, and renewable projects sited in the Outer Continental Shelf and coastal wind zones surveyed near Cape Mendocino and Point Conception.

Coastal regions face threats from sea level rise linked to climate change, oil spills exemplified by the Exxon Valdez oil spill and the Refugio oil spill, overfishing that prompted management by agencies like the National Oceanic and Atmospheric Administration and the Fisheries and Oceans Canada, habitat loss affecting sites such as Bolsa Chica Ecological Reserve and Tijuana Estuary, and invasive species including European green crab and Caulerpa taxifolia. Conservation responses include protected areas like Pacific Rim National Park Reserve, Olympic National Park, Redwood National and State Parks, Channel Islands National Park, and binational initiatives under accords such as the North American Free Trade Agreement-era environmental cooperation plus transboundary stewardship projects among indigenous authorities, municipal governments, and NGOs like The Nature Conservancy and World Wildlife Fund.

Category:Coasts of North America