ExploreNorth, your resource center for exploring the circumpolar North

Return to the Home Page The ExploreNorth Blog Arctic & Northern Books About ExploreNorth Contact ExploreNorth

Search ExploreNorth



The Terrains and Climate of Alaska

by Bill Jones


    Most perceive all of Alaska to have an Arctic climate. That, however, is not the case. Consider these comparisons:

  • 1. Central Alaska is the same latitude as Iceland, mid Norway, and Sweden.
  • 2. Southern Alaska is the same latitude as the lower Hudson Bay, Denmark, Scotland, Southern Norway and Sweden, Moscow, Leningrad, and the Baltic Sea.
  • 3. Only about one third of Alaska is north of the Arctic Circle.
  • 4. Alaska's Aleutian Islands share their latitude with lower British Columbia, Alberta, Saskatchewan, Manitoba, mid Ontario, Germany, London, and Newfoundland.

    Click here to see an accurate and broad map of the Alaskan Arctic that you can scroll about and refer to as the text describes the regions.

    The latitude comparisons above do not necessarily indicate a similar climate. In some instances, the Alaskan climate is either milder or harsher than other places along the same latitude. Climatic differences are generally caused by the shield of mountains and the maritime influence.

    The Alaskan Arctic extends some 300 miles from the Arctic Circle northward to the shores of the Arctic Ocean. The Arctic Steppes slope northward to reach the Arctic Tundra Plains, a band of treeless tundra meadows some 90-130 miles in depth, 600 miles wide in Alaska, and twice more that distance eastward across Canada to the upper Hudson Bay. This entire northern Arctic territory accommodates the scores of rivers that drain the northern Continental Divide, the Mackenzie River in Canada and the Colville River in Alaska being the largest. The northern edge of the Arctic Tundra Plains is the Arctic Ocean and its gulfs, bays, and sounds.

    The climate in the Arctic Tundra Plains is characterized by storms with high winds and blowing snow, deep cold of 40 to 70 degrees below zero (F) from November through March, long nights and short days. Winds are common during all seasons and there is heavy snow from fall to spring that buries the earth to depths of six feet or more. From early December to mid January the sun does not appear above the horizon. High noon is dim twilight And, in June through July the sun does not set below the horizon. Midnight in June is twilight. During the summer the snow melts to form thousands of lakes and flowing rivers. The air becomes dense with mosquitoes and black flies making human life untenable except along the coast.

    Throughout this 2500 miles of arctic coast there are only two roadways. One is the Dalton (pipeline road) in Alaska from Fairbanks to Prudhoe Bay. The other is the Dempster Highway from Dawson City in the Yukon Territory to Inuvik. The straight line distance between Prudhoe Bay and Inuvik is 500 miles. Except at these two points, all of the Inupiaq and Inuit tribes depend entirely upon air transport to bring in supplies and take out their trade goods. Their villages are so isolated that much of their ancient culture remains intact. Hunting and trapping are still common, although using modern tools such as guns, snowmobiles, and outboard motors on their boats.

    Looking to the west of Prudhoe Bay, the Colville River drains the western Brooks Mountains. This river flows through a valley formed between the Brooks Mountains and the Kiana Ridge, where it is believed that the Ipiutak, an ancient people lived. The large pre-historic town of Tiagra reveal 800 lodge pits of this extinct culture (near Point Hope). This ancient village was home to about 8,000 people, with 800 permanent and another 800 less permanent lodges, each housing five people.

    Such a populated town is larger than any present Eskimo or Indian town in Alaska or Canada and indicates an advanced cultural organization during an ancient time. That there would be only one such Ipiutak town defies logic. How many towns and the total population are not known.

    There is another ancient culture village (Upeagvik) near Point Barrow. The Birnirk people, now extinct, lived in this village some 2500 years ago or before.

The Anatomy of the Arctic Tundra Slopes

    During the short summers the arctic tundra slopes accommodate the largest herds of wild animals in the world. Called the skin of the earth by the Natives, the tundra is a spongy 1-4 foot thick mat on top of the earth and is a living microcosm of grasses, lichens, tiny flowers, and berries, nourished by the captured snowmelt on top of the permafrost below. The caribou migrate there in huge herds to bear their calves. Wolves, polar bear and grizzly bear come too, and some these are resident animals. Other resident wildlife are Arctic hare, lemmings, snow owl, raven, ptarmigan, wolverine, ermine, fox and musk ox, to name a few. Wild sheep and goats reside in the higher elevations of the Brooks Mountains. The caribou herds remain during the summer to graze the rich tundra, then migrate south across the passes of the Brooks Mountains to the subarctic rivers and forests in the fall. Great flocks of birds migrate to the tundra slopes from as far away Florida and Mexico. The large flocks include geese, swan, crane, egret and numerous species of duck. Some molt and become land borne, and all hatch their chicks during the summer months, teach them to fly, and then they migrate south in the fall. Nowhere on earth is wildlife more abundant than in the Arctic Tundra Slopes during the summers.

    The vastness of the tundra slopes can be realized only by viewing it from above. When one looks down during a flight in summer a panorama of green pasture extends from below to the wide horizon with uncountable numbers of caribou always in sight. Or in winter one sees a bleak white world dotted occasionally with a small family of musk oxen. Usually they are spotted first by a small cloud of ice fog that rises above the family in the snow. Then as the airplane approaches the north coast an isolated group of huts of a small village appear.

    In winter the sea is frozen and it is difficult to discern where land ends and the Arctic Ocean begins. In these small coastal villages live the clans of Inupiaq Eskimo (Inuit in Canada). They are the ice hunters who go miles out on the ocean ice to hunt seal, walrus, polar bear and whale all year. The caribou are their quest when summer comes. The Eskimo villages dot the Arctic coast around Alaska and Canada's north. A few of the largest villages might house several hundred people, but the population of most are fewer than two hundred. These villagers have no near neighbors and the distance between are more than fifty miles on average.

The Southern Arctic Region of Alaska

    Alaska's Arctic, that is to say the land mass above the Arctic Circle, is split in half by the Brooks Mountain range (The Continental Divide). The Brooks Mountain Range extends across Alaska in an unbroken arc from near the western coast to the eastern border with the Yukon Territory. Averaging 6,000 feet in height, the Brooks is the oldest mountain range in Alaska. Once an active rim of volcanoes, the Brooks is now semi-dormant, with only a few smoking volcano vents. Yet there are many thermal hot springs along both the northern and southern slopes, the larger springs providing water for the rivers even when the winter temperature is sub zero.

    The Nunamuit people live in a high mountain pass of the Brooks Mountains 120 miles north of the Arctic Circle. Classified as a distinct culture by the University of Alaska, and once threatened by extinction, the Nunamuits are likely the most unique people on earth. They are a beautiful people, light tan of complexion, with almond shaped expressive eyes, and with delicate facial features. They are quick to humor, and friendly by nature. Their culture has a religious affinity to the Brooks Mountains believing that each peak of the mountains have benevolent spirits, which beliefs spiritually binds them to the mountains. Back during the 1930s several small family groups or bands of people were found to be existing along the mid Brooks Mountains. They were unique and they were culturally interrelated. They were also threatened with extinction. The US government assisted the groups to unite into one community. The Nunamuits agreed and chose to live at Anaktuvuk Pass, a 2200 foot high pass in the mountains where they have lived happily since. The village of Anaktuvuk lies in a narrow pass in the mountains which is a principal route of migration of the Western Arctic Caribou Herd. The people and the caribou are together in this quaint village during the herd's twice-a-year migration. Anaktuvuk, at last count, had some 270 people of this distinct culture.

    The Noatak National Preserve lies in the western Brooks Mountains and includes Anaktuvuk village and pass. Here there are two branch wings of the Brooks Mountains. The Noatak River forms up from snow melt near Anaktuvuk and flows westward nearly 400 miles to the Chukchi Sea. The Noatak river is classified as a wild and scenic river for its entire length, and is the largest un-touched mountain ringed river in North America.

    The Brooks Mountains, an Arctic Shield: The Brooks Mountains serve as a barrier against winds and the heavy Arctic air to insulate half of Alaska's Arctic territory. Thus the lower half of the Alaskan Arctic is given a less harsh subarctic climate and it has sparse rain and snowfall. This southern half of Alaska's Arctic are the Alaskan steppes which gradually slope to the Kobuk, Koyukuk, Yukon, Chandalar, and Porcupine river valleys. Within this 150 mile north/south band there is a furthest north tree line that exists some halfway down these broad steppes. The scrub growth at the tree line changes to ever-larger growths of dense fir, aspen and birch forests in the river valleys.

    Just to the south of the Arctic Circle, a varying distance from the Circle, are the White Mountains, which extend east and west. Through the valley between the Brooks and White mountains flows the Yukon and Porcupine Rivers. These two principal rivers and their long tributaries form the principal watershed of Alaska and the Yukon, draining a region that is more than 2000 miles wide.

    The climate in this region is rather mild and dry in comparison with the true arctic climate along the north slopes and coast. The summers are somewhat longer, beginning in early June and extending through mid September. Daily mid-day temperatures range as high as 90°F from June through July.

    The Brooks Mountains shield this region from the fall and winter howling blizzards of the North. Winters do bring short periods of low temperatures of -50°F and sometimes -70°F, but there is little wind and the air is crisp and dry. Throughout the winters the temperatures are mostly between -25°F and -35°F. High pressure systems bring in clearing of the skies and arctic cold. Low pressure systems bring clouds and warming.

    Alaska's Arctic Rivers: To the south of the Brooks Mountains, above the Arctic Circle, are four principal river valleys. The Kobuk River flows westward through the Kobuk valley to drain the Schwatka mountain ridge. The Kobuk is about 400 direct miles in length and it empties into the salty Selawik Lake which is actually a bay off Kotzebue Sound. The entire Kobuk River is north of the Arctic Circle. The native people of this area are the Kobuk Inuit.

    The Yukon River flows northwest from Canada until it reaches the Arctic Circle at Fort Yukon. At Fort Yukon the Porcupine River joins the Yukon and the larger river is diverted westward and south by the up-rise of the Brooks slopes.

    The Yukon River valleys and all of its tributary rivers and valleys in Canada and Alaska are the homelands of the Athabascan people of many tribes. Called Dene in the lower States and Canada, they call themselves Dinee in Alaska and in parts of Canada. Their traditional language is handed down from an ancient time and it is shared with some regional variations in nuance and syntax by the Navaho, Apache, and many other North American Indian tribes. One long held archaeology paradigm holds that all of the native people of North America migrated across the Bering Land Bridge (Beringia) during the Ice Age. If that is true then perhaps the Athabascan might be the oldest survivingculture of the world.

    Just to the west of Fort Yukon the large Chandalar River joins the Yukon. The Chandalar River has three major forks that drain parts of the Brooks range. These wooded valleys and those of the Porcupine River are the home lands of the Gwich'in culture (Athabascan) people. In Alaska, the Gwich'in culture extends from the Yukon River about 200 miles North to the Brooks Range and from Beaver up the Yukon and Porcupine Rivers to the town of Old Crow in the Yukon Territory. From there the Gwich'in home range extends some 300 miles into Canada to beyond the Mackenzie River. The Gwich'in home range encompasses approximately 90,000 square miles, larger than the state of Pennsylvania.

    North of the Yukon River is another large forested arctic river valley. The Koyukuk River collects the waters of several smaller rivers that drains part of the Brooks Range. The Koyukuk River flows southwest to join the Yukon some 400 miles down stream from Fort Yukon. The people of the Koyukuk valley are primarily of the Koyukon culture (Athabascan), however Alatna is a traditional Kobuk Inuit village on the north bank of the river across from the Athabascan village of Allakaket. A sub tribe of the Koyukon culture in the upper Koyukuk river is the Koyukukhotana.

    The Yukon Flats: Further to the southwest of Fort Yukon, the Yukon valley closes and forms a natural dam at Rampart, which slows the river flow and forms a web-like deeper river with still waters. This segment is named the Yukon Flats. The tremendous and undauntable flow of the Yukon River breaches the natural dam at Rampart and picks up speed to reach the ancient village of Nuchalawoya (now Tanana) where the Yukon is joined from the south by the large Tanana River, which drains the Alaska Range. The Tanana River Valley lies between the White Mountains to the north and the Alaska Range to the south. The valley is about 100 miles south of the Arctic Circle, and including foothills, is about 100 miles wide and 350 miles long. The valley is home to three existing culture and one extinct culture. Click here to pull up a detailed map to view the cultural homelands and the topography of this region.

    Now we have explored the Arctic Regions of Alaska and a tiny segment of the Yukon River. To explore the upper Yukon River you may pull up the following Click here to see a map of the upper reaches of this great river and its tributaries in Canada.

    Click here to see a map of the center segment of the Yukon River, which also depicts the topography and cultures of some mentioned areas in the text.

    Finally, let us finish our trip down the Yukon River to its isthmus and view a map of the lower Yukon Valley.

    There is more to come about Alaska. Southern Alaska is known as the banana belt by we Northerners. Next week will bring more. See you then...

Bill Jones


More Features & Maps by Bill Jones