Arctic Desert
The Arctic Desert is a unique and extreme biome located primarily in the northern Arctic region, characterized by its cold climate and low precipitation levels. Despite being classified as a desert due to its annual precipitation of only four to six inches, similar to that of the Sahara, it features a landscape almost continuously covered in snow and ice. The average temperature in the warmest month remains below 50 degrees Fahrenheit (10 degrees Celsius), with winter temperatures plunging to minus 94 degrees Fahrenheit (minus 70 degrees Celsius) in some areas. The flora and fauna found here are specially adapted to survive these harsh conditions, with vegetation covering only about five percent of the ground, primarily consisting of low-growing herbs, mosses, and lichens.
Wildlife in the Arctic Desert is limited, with no reptiles or amphibians present due to the extreme cold. Notable species include polar bears, Arctic wolves, and various migratory birds that visit during the brief summer months. The region is facing significant environmental changes attributed to climate change, including rising temperatures and melting ice, which threaten the delicate balance of its ecosystems. Additionally, about four million people inhabit the Arctic, including Indigenous groups who rely on traditional subsistence lifestyles, as well as industries like oil and gas exploration. The ongoing changes in the Arctic Desert raise concerns about biodiversity, food security, and cultural impacts on local communities.
Arctic Desert
- Category: Desert Biomes.
- Geographic Location: Arctic
- Summary: This northern desert has more life than its Antarctic counterpart but is almost perpetually covered in ice and snow.
The ecosystem of the Arctic Desert is largely in the northern Arctic region and does not necessarily correspond to the Arctic Circle (65.5 degrees north latitude) or any political boundaries. The Arctic Desert is defined by a climate with an average temperature below 50 degrees Fahrenheit (F) (10 degrees Celsius (C)) in the warmest month. This region qualifies as a desert because of its extremely low precipitation, measuring four to six inches (100 to 150 millimeters) per year—about the same amount of precipitation as in the Sahara Desert. This is drier than the typical Arctic tundra zones, where precipitation averages up to ten inches (254 millimeters) annually. The small amount of precipitation in the Arctic Desert falls as snow. The temperature is so cold that the snow does not melt, so the land is covered in snow and ice. The region is not considered to be arid because of its low rates of evaporation. Even in the deserts, air humidity is high and soils are moist during the summer growing period.
Species richness in the Arctic Desert is low and further decreases toward the North Pole. Net primary production, decomposition, and net ecosystem production rates are low. Food chains are short, and there are few species at each level within the chain.
The Arctic Desert only has summer and winter seasons. In the summer, the sun is in the sky up to 24 hours per day, yet the temperature stays below 50 degrees F (10 degrees C). In the winter, there are several weeks when the sun never rises and temperatures get very cold—down to minus 94 degrees F (minus 70 degrees C). Snow can fall even at these incredibly cold temperatures as long as a source of moisture exists. The heaviest snows occur in near-freezing temperatures, or 14 to 32 degrees F (minus 10 to 0 degrees C). Typically, the air is so cold that it can hold only very small amounts of water, so snow does not fall often. In the winter, precipitation is very light and can be “diamond dust”a ground-level cloud of tiny ice crystals. Diamond dust can occur even on clear-sky days and events can last for several days.
Temperatures within the northern Arctic vary by location. In Greenland, cold water flowing south in the ocean creates cooler temperatures than in the northern European areas, where warm waters flowing in the Gulf Stream warm the land. Eastern Canada (51 degrees north latitude) has polar bears and tundra, for example, and Norway (69 degrees north latitude) supports agriculture.
Terrain and Ecosystems
Seas and mountains, such as the Brooks Range in Alaska, fragment the Arctic land masses. Seas separate large Arctic islandsincluding Svalbard, Novaya Zemlya, Severnaya Zemlya, New Siberian Islands, and Wrangel Islandand the land masses of the Canadian archipelago and Greenland. Similarly, the Bering Strait separates the Arctic lands of the Old and New worlds.
Soils form slowly in the Arctic Desert; they typically are shallow and underdeveloped. Low nutrient concentrations in the soils correlate to low vegetation productivity. A layer of permanently frozen subsoil called permafrost exists, consisting mostly of gravel and finer material. Permafrost can extend downward for up to 0.6 mile (one kilometer). Water in the Arctic Desert is permanently frozen, although waters in the southern Arctic will melt in the summer.
Ecosystems in the Arctic Desert are disturbed through mechanical and biological processes that affect organism colonization and survival. Mechanical disturbances include freezing and thawing cycles in the soils, wind, seasonal changes in ice, flooding, and erosion. Biological disturbances include outbreaks of insect pests, high variance in the numbers of grazing animals from year to year, and fire.
Animal Life
The extreme conditions of the Arctic Desert limit the life found there. The desert has no reptiles or amphibians because it is too cold for them to survive. The native animals have adapted to handle long, cold winters and to breed and raise young quickly in the summer. Animals such as mammals and birds also have additional insulation from fat. Many animals hibernate during the winter because food is not abundant. Another alternative is to migrate south in the winter, as birds do. Due to constant immigration and emigration, the population oscillates.
The top carnivores are polar bears and Arctic wolves. Polar bears are the largest land-based carnivores in the world. Male polar bears weigh 772 to 1,499 pounds (350 to 680 kilograms), and females weigh 331 to 549 pounds (150 to 249 kilograms). Their thick white fur provides camouflage in the snow and ice and is thick enough to keep them warm. Their primary food source is seals, which they hunt from sea ice. Their large, wide paws help the bears walk on the snow and they can kill a seal with just one swipe. The bears roam the shores and swim far out to pack ice and their nostrils can close when swimming underwater. Polar bears are considered to be a threatened species. Polar bears play an important role in controlling seal populations, while the seal population limits the bear population. Scientists estimate that 20,000 to 25,000 polar bears live in the Arctic.
Other carnivores are Asian snow leopards, Arctic foxes, ermines, and wolverines. Large herbivores include caribou and muskox; smaller herbivores include hares and lemmings. Offshore are many aquatic mammals, such as walrus, ringed seals, bearded seals, and whales including the beluga and narwhal. Birds found in the northern Arctic generally migrate there in early summer and leave by the end of the season. Birds of prey include owls and hawks; waterfowl include geese, ducks, and loons.
Plant Life
Vegetation in the Arctic Desert covers five percent or less of the ground due to a very short, dry growing season. This is due to dry air, permafrost, poor soils, and lack of pollinating insects. The entirety of the northern Arctic lies above the tree line, so no full-size tree species grow here. Very few plant species can survive in these conditions. Plants are generally stunted and become more so to the north. These herbs, along with mosses and lichens, stand less than four inches (ten centimeters) high.
The plants as a whole are specially adapted to the harsh winds, low water availability, short growing season, and poor soils. Arctic plants grow in clumps for additional protection from snow and wind. They are able to carry out photosynthesis even in low light conditions and extreme cold, which most other plants could not withstand. Due to the short growing season, these plants reproduce by budding and division.
Environmental Changes
The Arctic is experiencing dramatic environmental changes likely to affect Arctic ecosystems for many reasons profoundly. Temperatures have already increased in some parts of the Arctic, and future global climate changes are expected to be greatest in the northern regions. The Arctic Desert has a longer snow-free period than other parts of the Arctic, which has increased by five to six days per decade.
Stratospheric ozone has been depleted over recent decades, by a maximum of 45 percent below normal in the high Arctic in spring. This has probably led to increased UV-B radiation reaching the Arctic's surface. Arctic plants may be susceptible to increases in UV-B radiation because the low temperatures limit repair to DNA damage. In the future, temperatures in the Arctic could increase by more than two to five degrees C (3.6 to 9 degrees F).
Climate change is the primary factor threatening biodiversity here. Recent satellite data from 2023 shows Arctic sea ice reached its sixth-lowest minimum on record, with polar bears now losing about seven weeks of crucial seal-hunting time compared to 1979 due to earlier ice melt. Current and predicted environmental changes are likely to add more stresses and decrease the potential for ecosystem recovery from natural disturbances while providing thresholds for shifts to new states—when disturbance opens gaps for invasion of species new to the Arctic, for example. Many species may not be able to thrive in their current environment under different climate conditions. Relocation is the most likely response for most species. Some species will not be able to relocate, such as polar bears. Rapid changes in climate beyond organisms' ability to relocate could lead to increased fires, disease, and pests.
Warming in the high Arctic could change the amount of vegetation cover, biomass, and types of reproduction. There could be an increase in sexual proliferation instead of colonial reproduction. As permafrost melts with warming temperatures, decomposition in soils increases, often releasing methane and related greenhouse gases. A lack of soil nutrients will likely limit major vegetation changes.
Human Activities
Approximately four million people live in the Arctic worldwide, and about one-tenth of that population belong to Indigenous groups. Inuits there maintain subsistence lifestyles, existing on the food they can hunt, catch, or fish. Oil and gas exploration and tourism are other sources of income. In 2021, Alaska had 2.4 million barrels of crude oil, making it the fourth-largest oil-producing US state.
Climate change in this region could alter people's food, fuel, and culture. It could have a global economic effect due to changes in oil and gas exploration as more land becomes available with melting ice. Future effects on the moisture content in the Arctic Desert are extremely difficult to predict.
Bibliography
McCord, Howard. The Arctic Desert. Stooge Editions, 1975.
National Snow and Ice Data Center. "Arctic Sea Ice News & Analysis." NSIDC, 2023, nsidc.org/arcticseaicenews. Accessed 9 Nov. 2024.
Pielou, Evelyn. A Naturalist's Guide to the Arctic. University of Chicago Press, 1994.
Sorokina, Anna. "Why Do People Choose to Live in the Arctic Desert?" Russia Beyond, 14 Feb. 2022, www.rbth.com/travel/334764-arctic-desert-russia. Accessed 9 Nov. 2024.
Woodford, Chris. Arctic Tundra and Polar Deserts. Heinemann Raintree, 2010.