U.S. DEPARTMENT OF THE INTERIORBUREAU OF LAND MANAGEMENT
 
Print Page

Alaska's Cold Desert

Three Regions

map of 3 regions

Arctic Alaska, the area of the state north of the Arctic Circle, has three distinct regions: the arctic coastal plain, the Brooks Range, and the boreal forest with its numerous lakes, rivers, and streams. 

The arctic coastal plain, or the "North Slope," includes 14 percent of Alaska's land. Blanketed by tundra and dotted with lakes and ponds, it receives less than 16 centimeters of moisture annually (less than the Mojave Desert). Despite meager precipitation, most of the coastal plain is classified as wetlands. The underlying permafrost (permanently frozen ground) inhibits drainage, and the small amount of melt water or rain that soaks into the tundra remains near the surface. Most inhabitants of the North Slope live in one of eight communities, seven of which are along the coast. The largest communities are Barrow and Kotzebue. Barrow, at about 1,300 kilometers from the North Pole, is the northernmost inhabited village in North America.

South of the North Slope lie the rugged peaks of the Brooks Range, which runs across northern Alaska for 1,150 kilometers. The range rises over one kilometer at its western end, and nearly three kilometers in its eastern peaks. Although white spruce and other trees appear in some sheltered valleys, the slopes are generally bare except for a thin layer of hardy tundra vegetation, such as lichen. From the highest peaks, rivers flow south to the Yukon River, north to the Beaufort Sea, or west to the Chukchi Sea.

Whale HarvestBrooks Range
A Whale Harvest in Barrow, one of the eight communities of the north slope.The rugged peaks of acrtic Alaska's Brooks Range rise from one to three kilometers.

The south slope of the Brooks Range, sheltered from ocean winds, grows more varied tundra vegetation and forests of small trees. The Russians called this region "taiga," a land of scattered dwarfed conifers, and for good reason: Trees grow so slowly in the taiga that scientists have measured century-old spruces with trunks no more than 30 centimeters in diameter. The average white spruce in the taiga is only six meters high, even after a century of growth.

 

 
Adaptations

In order for arctic animals to survive in their arid, windy, and frigid environment, nature has equipped these creatures to find food and shelter and to produce offspring. The accompanying foldout highlights many of the unique adaptations of arctic plants and animals and provides activities that can help students understand how adaptations work.
Arctic Alaska's human inhabitants have also adapted to cope with the environment. With temperatures averaging well below freezing during most months, the need to stay warm is paramount. Semi-subterranean "pit" houses were used from prehistoric times until recently. These homes, built of sod and other natural insulation, were very efficient at holding in the heat. Modern arctic houses now resemble those in the lower 48 states, yet contain more insulation and are often built on pilings to allow cold air to circulate under the house. This ensures that the warmth of the house won't melt the underlying permafrost and cause the structure to sink.

Ongoing Management Challenges

Over two-thirds of arctic Alaska is federally owned land, managed by the Bureau of Land Management, the U.S. Fish and Wildlife Service, and the National Park Service. Americans depend on these agencies to properly manage Alaska's tundra regions to meet a variety of human and environmental needs. In meeting their responsibilities, these agencies are grappling with a number of tough environmental challenges and issues.

The Fragile Tundra. The soils of the Arctic are very susceptible to damage if disturbed by animals or humans. Some biologists estimate, for example, that it may take up to 40 years for lichens to recuperate from the munching and treading of a passing herd of caribou (some lichen growth has been measured at a sixth of a centimeter per year).

Flower
Brilliantly colored flowers bloom in the arctic summer. Photo: Daniel Gullickson, BLM
The land of the North Slope is underlain with permafrost, insulated on top by shallow-rooted, low-lying vegetation. In the summer, the sun's radiant energy thaws the frozen surface down about 10 centimeters, with the melted snow water unable to seep into the frozen ground below. Consequently, the region is largely wet and boggy, with over a million shallow lakes. Crossing the terrain by foot in the summer is difficult, because the surface consists of areas of elevated grassy tussocks alternating every 10 centimeters with small, sunken pools of stagnant standing water.

As long as the permafrost is insulated from heat by the surface vegetation, it can remain stable for many thousands of years. On the other hand, even small disturbances to the vegetation rootmat can start a process of destabilization that can reach impressive proportions.

Experience has taught us about the fragile nature of this land. In the post World War II period, exploration for oil and gas involved the use of mechanized vehicles that damaged the insulating vegetation. When the vegetation was damaged, the permafrost was no longer insulated from the summer sun, causing the frozen soil to melt. Eventually, this resulted in massive artificial bogs and swampy areas. In some places, these scars, though decades old, are still evident.

Crossing the tundra without damaging the permafrost is an ongoing challenge. Much of today's permafrost degradation is triggered by road-building and other construction activities that strip away or disturb the vegetation. Over the years engineers have learned to work in winter and to avoid disturbing the vegetation. For example, in building the Dalton Highway, an all-weather road that extends north 650 kilometers from interior Alaska to the Prudhoe Bay oil fields, engineers placed the roadbed on top of the vegetation rather than cutting into the surface as is the common practice in road-building. In some areas, sheets of plastic-foam insulation were placed on the vegetation to provide additional thermal protection before the roadbed material was laid down. Moreover, mechanized vehicles may use the road only in periods of adequate snow cover (15 or more centimeters) in order to blunt the impact on the tundra. In other cases, temporary ice roads are built. Even air-cushioned vehicles have been tried as a way to avoid damaging the tundra.

Kanuti Flats
A summertime view of the North Slope's 
Kanuti Flats shows
 why the region is considered a wetland
Unfortunately, despite innovations in road and building construction, the fragility of the tundra remains a paramount issue in the Arctic today. Other concerns in the region include ozone depletion, solid waste disposal, and pollution of the Arctic Ocean.

Ozone Depletion. The effect of ozone depletion is of particular importance to life in the Arctic and Antarctic, as the phenomenon is most severe over polar regions. In the winters, "ozone holes" develop over the poles. Research points to certain human-made chemicals, chlorofluorocarbons, being major contributors to this situation. Researchers in the Arctic are investigating how plants that support the food chain may be impacted by ozone depletion.

Solid Waste Disposal. Disposing of solid waste is another major problem in the Arctic because permafrost limits the construction of sanitary landfills, and low temperatures inhibit bacterial decomposition of organic wastes. Scientists have detected the effects of human wastes from Inupiat (native Alaskan) settlements centuries after the inhabitants have gone. Today, organic waste is collected and hauled to sewage dumping areas or burned in oil barrels.

Pollution of the Arctic Ocean. Recent reports of nuclear waste contamination and massive oil spillages from broken pipelines in Siberia have once again raised concerns about pollution of the Arctic Ocean. The oil spillages have been near river systems that drain into the Arctic Ocean. Because the Arctic Ocean is a major source of fish, whales, seals, and walrus (of cultural and economic importance to local Inupiat), the consequences of polluting it would severely affect the human population as well as the environment in general.

Inupiat children. Wainwright, Alaska
Inupiat children from the village of Wainwright 
on the arctic Alaskan coast brave a howling winter storm. Photo: Fred Hirschmann
Global Warming.
About 14,000 years ago, arctic Alaska's climate began to change. Although the reasons for the change are not completely understood, the major factors of solar radiation, the winds of the jet stream, and ocean current fluctuation were involved. This climate change resulted in a major alteration in nature and caused the extinction of most of the Ice Age herbivores as well as the carnivores that preyed on them. A few large predators, such as the grizzly bear and wolf, survived, as did a few of the less common Ice Age herbivores that were better suited to the new ecosystem than the old one, such as moose, musk oxen, and caribou. It was a difficult time for the human population also, because of the declining food resources and the fluctuating climate.

Some scientists predict that the results of global warming over the next century will be very similar to the effect of past warming events on the permafrost and on the arctic ecosystem. Of special concern is the peat that lies beneath the tussock-tundra covering most of arctic Alaska, Canada, and Russia. These arctic peat deposits contain huge amounts of CO2; if the climate warms enough that the peat thaws and begins to decompose, all of that CO2 would be released into the atmosphere. The increase in atmospheric CO2 could cause an increase in surface temperatures, which in turn could cause the rate of peat decomposition to accelerate, generating more CO2. The onset of an ever-increasing CO2 production cycle in the Arctic could have a significant effect on ecosystems worldwide.

Ironically, a climatic alteration that brought the first humans to North America thousands of years ago may provide insight into a contemporary climatic change that could affect modern humans and alter the course of civilization once again.

Arctic National Wildlife Refuge

Musk Oxen
Musk oxen stand in a defensive posture. These animals were exterminated from the North Slope in the late 1800s by sport-hunters, but 64 musk oxen reintroduced into the costal plain in 1969 and 1970 have now multiplied to a thriving population of 550. Photo: L. David Carter, U.S. Geological Survey
T
he 7.7 million hectare Arctic National Wildlife Refuge, commonly referred to as "ANWR" (pronounced "anwar"), is the nation's largest wildlife refuge. ANWR supports 169 species of birds, 38 species of fish, 44 species of mammals, an unknown number of species of flowering plants, and more than 2,000 species of lichens and bryophytes (mosses and liverworts).

In recent years, Congressional debates about allowing oil and gas development in ANWR have brought attention to this issue. The question is, What are the impacts of oil and gas development, including pipeline construction, on wildlife and on the Inupiat and other northern peoples who subsist, in part, on this wildlife? Opinions vary on the answer, with some people predicting little effect, while others foresee drastic impacts brought about by substantial changes to the migration and calving patterns of caribou.

At stake for consumers is the nation's most promising onshore petroleum prospect. Geologists have determined that there is a 19 percent chance of finding recoverable oil deposits within ANWR's coastal plain. No one knows how large the potential oil reservoir is, but federal land managers estimate there may be enough oil in that field to supply at least 10 percent of the nation's fuel for the next 20 years.

Trans-Alaskan Pipeline
The Trans-Alaska Pipeline near the Richardson Highway. This line carries oil from Prudhoe Bay to Valdez. Photo: Fred Hirschmann
At stake for conservationists is the biologically productive arctic coastal plain. Often referred to as "America's Serengeti," the coastal plain

  • serves as an important calving ground for the Porcupine caribou herd;
  • contains about 75 percent of the year-round musk ox range;
  • provides an important gathering area for more than 100,000 lesser snow geese;
  • is frequently used for maternity dens by polar bears in winter;
  • and is used by birds from six continents, who flock there to raise their young.

Research may help answer some of the issues surrounding ANWR, but politics and the worldwide price of oil will no doubt strongly influence the progress of development in this part of the world.

Recreationists

Primarily as a result of the ongoing debate about the future of ANWR, an increasing number of wilderness adventurers have been visiting the refuge to see for themselves what the debate is about. The number of outfitters offering backpacking and river trips increased from one in 1975 to 15 in 1995. One result has been that the amount of river usage during the short summer has increased dramatically. A "visitor-use day" indicates one person using an area for all or part of a day; in 1984 ANWR had 702 visitor-use days, and in 1995 it had 3,182 visitor-use days. As a result, congestion on the rivers and air traffic in and out of the refuge have grown. As recreation use intensifies, so will impacts on the ecosystem, and decisions will have to be made on whether to limit access to ANWR.

Looking to the Future

Alaska's tundra seems immense, remote, and largely untouched by humans. Yet, as the human population in this region increases and as resource development grows, human actions will have a long-lasting and cumulative impact in the ecosystem. Meeting the needs of people today while protecting our resources for the future will be a big challenge.

As tomorrow's decision-makers, today's students will play a big role in determining how well we meet that challenge. Complex legal, political, ecological, economic, and social ramifications will have to be considered. Few issues will have simple solutions, and resolving them will undoubtedly involve compromise. By introducing children to these ideas now, educators can help prepare them for the future.

How a Sliver of Technology Tamed the Arctic

Archaeological evidence suggests that it wasn't until 14,000 to 13,000 years ago that humans migrated into North America by crossing from Siberia to Alaska via the Bering land bridge.

Most researchers agree that to survive in arctic and subarctic environments, ancient humans had to be able to make clothing that was generally form-fitting and relatively weather-tight. Such clothing was probably made by fastening pieces of animal hide together with sinew. The invention of the awl, a pointed implement used for stitching together animal skins for garments and other uses, was the technological breakthrough that most likely enabled ancient peoples to begin to colonize cold regions. The eyed needle, which evolved from the awl and is found on 30,000-year-old Russian campsites, would have allowed strong, weather-tight, and, in some cases, water-tight clothing seams to be made.

The importance of this small aspect of prehistoric technology--a simple needle--and its effect in terms of human occupation of the Western Hemisphere is almost unbelievable. Humans who settled in North and South America got there by migrating through the Arctic. Without the needle, they could not have done it.

Although it took roughly 15,000 years from the time that needles first appeared until humans were living in the Arctic, it can easily be said that this simple tool and those skilled in its use were responsible, in part, for the human occupation of the New World.

Back to the Alaska's Cold Desert Page


 
Last updated: 01-04-2008