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The Arctic Environment

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The Arctic Environment NATIONAL WILDLIFE FEDERATION ARCTIC The arctic Environment Background Imagine a cold, windy place where at times the sun hardly shines and at other times of year barely sets. It is a place with frozen ground, making it very difficult for trees to grow. Instead of walking through the forest, in the Arctic tundra, you walk on the forest, as plants may only grow a few inches to perhaps one foot tall. At certain times of the year a visitor might think the tundra appears barren, but during the sunny summers, the land bursts with wildlife and activity. What is the Arctic region? Literally defined, it is the area within the Arctic Circle, including the icy North Pole and the Arctic Ocean. One interesting feature of the Arctic is its many glaciers, rivers of ice formed from snow falling over thousands, even millions, of years. Glaciers spread and move with freezing and thawing temperatures and by the force of their own weight and gravity. Glaciers form on land, near lakes, and along the coast. When the tip of a glacier reaches the edge of the sea, it breaks off and forms an iceberg in a process called calving. The Arctic region also includes the tundra—meaning “treeless plain”— ecosystem. One defining characteristic of the arctic tundra is its BACKGROUND | 1 www.nwf.org ARCTIC NATIONAL WILDLIFE FEDERATION permafrost, permanently frozen activity guide will lead you and What are some of the conser- ground that occurs from several your students through explo- vation challenges facing the inches below the surface to rations of the arctic region, its North American arctic depths of more than 1000 feet. wildlife, people, and conservation regions? What can be done to Permafrost, combined with a long challenges, focusing on its North address them? season of cold and high winds, American component. This guide are the primary reasons for a will help you explore the Location and Climate nearly treeless zone in the arctic. following questions: The arctic tundra is circumpolar, Trees are unable to spread roots in Where is the arctic? meaning that it is an ecosystem the permafrost, and leaves and surrounding the polar region, branches would catch the wind What is tundra? above roughly 60 degrees north and be blown down. What characteristics define it? latitude. The Arctic circle occurs at 66 degrees north latitude. The northern boundary of the What species of wildlife live arctic tundra is the northern ice in the North American arctic In the arctic tundra, short days cap (ice cover, which includes the region? What adaptations do for much of the year and the North Pole). The taiga, also arctic wildlife have to survive harsh cold climate result in a brief called boreal (meaning northern) the extreme conditions? growing season of 50-60 days. By forest, is a zone of scattered ever- contrast, the growing season in green trees, and is the southern What peoples live in the temperate forests is about six boundary of the arctic tundra. North American arctic? How months long and in tropical The imaginary line where the do they live? forests lasts the entire year. treeless tundra changes to Furthermore, strong winter taiga is called the tree line. ARCTIC CIRCLE winds challenge the stability Arctic tundra is found in of any plants that grow Asia, North America, and more than an inch or two eight northern countries above ground surface. within Europe. Tundra Below a thin layer of soil also occurs in other places that thaws every summer is around the world, where ground that remains frozen cold and high winds year-round, called inhibit or prevent tree permafrost. The permafrost growth. Generally this may be incredibly deep, kind of tundra is found at reaching more than 1000 high elevation and is thus feet thick in some locations. known as alpine tundra. Although the tundra receives less than ten inches of The arctic is an amazing precipitation each year, and unique place. This (which is why it is some- 2 | BACKGROUND www.nwf.org NATIONAL WILDLIFE FEDERATION ARCTIC times referred to as an arctic tundra must be adapted to face desert), there can be plenty of these challenges, including not standing water when the upper only extremes of day length and layer of soil thaws each summer. temperatures, but also harsh During this thaw, water is winter winds, long periods of trapped at the surface by the below freezing temperatures, and ARCTIC POPPY always-frozen permafrost below, permanently frozen ground. forming extensive seasonal Hundreds of plant species have wetlands. Roads, which trap the adaptations allowing them to sun’s heat, must be specially insu- thrive in the arctic region. Plants lated to prevent them from that grow in the arctic are melting the permafrost, which adapted to grow very quickly in could cause their collapse. Since the short window of prime buildings also trap heat, to avoid growing conditions each summer. this problem, many buildings are Plants with low growing, small, or shape of a plant plays a role in constructed on stilts and insu- compact forms are the most its overall ability to function in its lated pipes run above ground. successful in the arctic—mosses environment; in other words, and lichens, grasses and low form follows function. Small, Flora and Fauna bushes are good examples. They waxy leaves help some tundra Due to its high latitude and the are adapted this way not so much plants retain moisture, and tilt of the earth, the arctic experi- to conserve heat, as animals do, vertical leaves (such as a blade of ences light and temperature but to conserve water. When grass) help others get more light extremes throughout the calendar surface area is lower, water evapo- when the sun is very low on the year. Temperatures range from ration is also lessened. The form horizon. Tundra plant roots tend 60°F (50° C) in to spread horizontally through the winter to the thin soil layer above the 77° F (25° C) in permafrost, rather than vertically. the summer. In Barrow, Alaska, The form of a plant is one type of on the northern adaptation, but arctic plants have coast, there is a 67- many others. For example, some day-long period of plants contain chemicals which darkness beginning serve as natural antifreeze, November 18. enabling them to continue photo- May 10 starts an synthesizing in freezing tempera- 84-day-long tures (water is a necessary part of period of light. the process of photosynthesis). The plants and Furthermore, all plants must animals of the reproduce and many cannot rely BACKGROUND | 3 www.nwf.org ARCTIC NATIONAL WILDLIFE FEDERATION largely on insect pollinators KRUMHOLZ since insects’ period of activity in the arctic is limited. Many arctic plants therefore reproduce from pieces of themselves, such as a bulbil or root runner below the ground. Interestingly, the very condi- that are made up of two coex- penetration with the near-surface tion that challenges the overall isting organisms, each helping the permafrost, and a low growing survival of arctic plants so much, other to survive. Each lichen is a form is less likely to catch the the wind, is essential to many of combination of a fungus, which wind and become uprooted. them for spreading their pollen. stores water and collects minerals, Only very low-growing dwarf Sometimes plants have to “coop- and an algae, which photosynthe- willows and birches survive on erate” with each other to survive. sizes, providing energy for the the tundra, and they may only This is called a symbiotic rela- lichen using the water collected reach a few feet in height. tionship. Lichens are organisms by the fungus. At the southern edge of the arctic ARCTIC LICHEN Tundra conditions—especially tundra, in what is called the tran- permafrost and high winds — sition zone between evergreen prevent trees from taiga forest and the nearly treeless growing to the land of the tundra, there are trees heights found natu- growing that look like they are rally in many other walking across the tundra. These parts of the world. krummholz, or “twisted wood,” This is because the are trees that grow on one side, root system of the the side away from the wind. On tree has limited soil this side, they have branches that reach out and touch the ground, FOOD WEB POLLUTION IMPACTS IN THE ARCTIC eventually taking root there. Wind hitting the tree on the Lichens absorb and store radioactive materials very easily other side causes it to lean in the because these chemicals mimic potassium, a mineral important direction of growth. This gives for lichen growth. The Chernobyl nuclear power plant accident the krummholz the appearance of affected lichens of the Norwegian arctic, which impacted rein- moving, almost crawling across deer that rely on lichens as their main food source. Scientists the tundra. These trees may be found that these reindeer had radiation levels above government only several inches to a few feet safety levels, and could no longer safely be eaten by people. tall, (generally not taller than the amount of snow that falls each 4 | BACKGROUND www.nwf.org NATIONAL WILDLIFE FEDERATION ARCTIC year), but they can live for several shape to better eaten by wolves. An hundred years! conserve body aquatic food chain of heat. Several the Arctic Ocean Like plants, animal species inhab- mammals, includes phyto- iting the arctic tundra have including polar plankton eaten by special adaptations that enable bears, arctic fox, krill, which are in them to survive in an ecosystem and caribou, have turn eaten by that is dramatically different in hollow hair that whales.
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