In literature (especially Russian), the term "Alaska Peninsula" was used to denote the entire northwestern protrusion of the North Americancontinent, or all of what is now the state of Alaska, exclusive of its panhandle and islands. The Lake and Peninsulaborough, the Alaskan equivalent of a county, is named after the peninsula.
The Alaska/Aleutian Peninsula is also grouped into Southwest Alaska.
The southern side of the Alaska Peninsula is rugged and mountainous, created by the uplifting tectonic activity of the North Pacific Plate subsiding under a western section of the North American Plate; the northern side is generally flat and marshy, a result of millennia of erosion and general seismic stability. The northern and southern shores are likewise quite different. The northern Bristol Bay coastal side is generally turbid and muddy, experiences tidal extremes, and is relatively shallow; the Pacific side, which is also known as the "ring of fire",[5] has relatively small tidal activity and the water is deep and clear.
Average annual precipitation ranges from 24–65 in (610–1,650 mm). Coastal areas are subject to intense storms, wind, and rain. Winter temperatures average between 12 and 34 °F (−11 and 1 °C), and in summer between 43 and 59 °F (6 and 15 °C). Frosts can occur any day of the year at higher elevations.[6][7] The climate can be compared to that of parts of Scotland, the Aleutian Islands, Iceland, and Tierra del Fuego.
The Alaska Peninsula is home to some of the largest populations of native and undisturbed wildlife in the United States. Besides the famous McNeil River and KatmaiAlaskan brown bear populations, large herds of caribou, moose, wolves, waterfowl, and willow ptarmigan inhabit the area. The bears of the peninsula and Bristol Bay are so numerous because they feed on the world's largest sockeye salmon (Oncorhynchus nerka) runs, which occur here in large part because the many large lakes of the peninsula are an important element in their lifecycle. These salmon, after returning from their brief time at sea, swim into the lakes and their contributing streams to spawn. Their offspring, or fry, overwinter in the deep and food-abundant depths of these lakes until their migration to the sea in one or two years.
The rugged southern half of the peninsula, and also the Kodiak Archipelago which lie off the south coast of the peninsula and are home to even more bears, constitute the Alaska Peninsula montane taigaecoregion and contain a number of protected areas such as Katmai National Park. Vegetation on the Peninsula consists mostly of shrub-lands, grassy meadows, or wet tundra.
