Алясканың Кобук өзені ұлттық паркі

National park in Alaska, United States

Kobuk Valley National Park is an American national park in the Arctic region of northwestern Alaska, located about 25 mile (40 km) north of the Arctic Circle. The park was designated in 1980 by the Alaska National Interest Lands Conservation Act to preserve the 100 feet (30 m) high Great Kobuk Sand Dunes Kobuk Valley is one of eight national parks in Alaska, the state with the second most national parks, surpassed only by California which has nine. The park is managed by the National Park Service. Since no roads lead into the park, visitors arrive via chartered air taxi from Nome, Bettles, or Kotzebue. Flights are available year round, but are weather dependent. The park is one of the least visited American national parks, along with others inaccessible by road, including the neighboring Gates of the Arctic, Isle Royale in the middle of Lake Superior, the Dry Tortugas at the end of the Florida Keys, as well as Katmai and Lake Clark in southern Alaska.

The park is the center of a vast ecosystem between Selawik National Wildlife Refuge and the Noatak National Preserve. It is over 75 mile (121 km) by river to the Chukchi Sea. The Gates of the Arctic National Park and Preserve lie 32 mile (51 km) to the east. The park includes about of lands owned by native corporations and the State of Alaska. The park consists of the broad wetlands valley of the Kobuk River which runs along the southern edge of the western Brooks Range, which is known as the Baird Mountains. The boundary of the park runs along the height of land of the Baird Mountains in the north and the shorter Waring Mountains in the south that form a ring, defining and enclosing the Kobuk Valley. The middle two thirds of the Kobuk River, from just above Kiana to just below Ambler, is included in the park, as are several of its major tributaries such as the Salmon River and the Hunt River. The valley floor is mainly covered by glacial drift. Three sets of sand dune fields are located on the south side of the Kobuk River. The Great Kobuk Sand Dunes, Little Kobuk Sand Dunes and the Hunt River Dunes are remnants of dune fields that covered as many as immediately after the retreat of Pleistocene glaciation. A combination of outwash deposits from the glaciers and strong winds created the field, which is now mostly covered by forest and tundra. In present times the active dune fields cover about The Great Kobuk Sand Dunes comprise the largest active Arctic dune field in North America. NASA has funded their study as an analog for Martian polar dunes. The park's headquarters are at the Northwest Arctic Heritage Center in Kotzebue, about 100 mile (161 km) west of the park on the Bering Sea coast. Seasonal ranger stations are operated along the Kobuk River at Kallarichuk, at the west end of the park, and at Onion Portage at the east end of the park. Offices and visitor services for Cape Krusenstern National Monument and Noatak National Preserve are in the same facility. The units are managed together as the Western Arctic National Parklands, with a single Park Service superintendent in charge.

According to the Köppen climate classification system, Kobuk Valley National Park has a Subarctic climate (Dfc) with cool summers and year around precipitation. Dfc climates are defined by their coldest month averaging below 0 °C (32 °F), 1–3 months averaging above 10 °C (50 °F), all months with average temperatures below 22 °C (71.6 °F), and no significant precipitation difference between seasons. According to the United States Department of Agriculture, the Plant Hardiness zone at Kallarichuck at 13 ft (4 m) elevation is 2a with an average annual extreme minimum temperature of 47.1 °F ( 43.9 °C). Weather in the park is subject to extremes. Average low temperatures in January are , and can reach nighttime lows of Summer temperatures average around , and can reach Since the park is above the Arctic Circle, the sun does not set from June 3 to July 9, and the sun is visible for only 1 1/2 hours on the winter solstice, with long periods of twilight on either side of sunrise and sunset. As is the case over all of northern Alaska, the aurora borealis is often visible on winter nights when solar activity is high. Snow can happen at any time of the year. Wind and rain are common in summer.

The park lies in a transition zone between boreal forest and tundra. Large mammals in the park include wolf packs, Arctic and red foxes, caribou, and moose. Black bears, brown bears, beavers, river otters, Canadian lynxes, and Dall sheep exist in the park as well. Smaller mammals include wolverines, martens, minks, porcupines, muskrats, snowshoe hares and a variety of voles. Fish species include chinook, chum, pink and sockeye salmon, with other salmonids including Dolly Varden, Arctic char, lake trout and Arctic grayling. Other species include burbot, Arctic lamprey, round, broad and humpback whitefish, and pond and rainbow smelt.

Human habitation in Kobuk Valley is believed to extend back at least 12,500 years. The present inhabitants of the valley are the Inupiat people, who subsist on hunting and fishing in the region. The Onion Portage Archeological District is a National Historic Landmark district at the east end of the Kobuk River's course through the park. The site, strategically located at a major caribou river crossing, documents nine cultural complexes spanning from 8,000–6,000 BC to about 1000–1700 AD.