Many animals that live in the tundra, like the caribou and the semipalmated plover , migrate to warmer climates during the winter. Others, like the arctic ground squirrel , hibernate during the winter months. There are very few reptiles and amphibians found in the tundra because the temperatures are so cold. Tundra What Is the Tundra?
Defrosting the Tundra The growing season in the tundra is very short, usually only 6 to 10 weeks. Plants in the Tundra There are thousands of species of plants in the Arctic tundra. Living in the Tundra Animals that live on the tundra must be able to adapt to very cold temperatures.
What Is the Tundra? The relatively few species of plants and animals that live in the harsh conditions of the tundra are essentially clinging to life. They are highly vulnerable to environmental stresses like reduced snow cover and warmer temperatures brought on by global warming.
The Arctic tundra is changing dramatically due to global warming , a term that falls within a wider range of trends scientists now prefer to call climate change.
The impacts in this region are broad and somewhat unpredictable. Animals that are typically found further south, like the red fox , are moving north onto the tundra.
This means the red fox is now competing with the Arctic fox for food and territory, and the long-term impact on the sensitive Arctic fox is unknown. Other tundra denizens, such as the wolf spider, are growing bigger and thriving. Shrubs are getting taller , contributing to declines in the sensitive groups of lichen that caribou and other species depend on for food.
Lakes and ponds are evaporating or draining away. The Arctic's permafrost, the literal foundation for much of the region's unique ecosystem, is deteriorating with the warmer global climate. Permafrost is a layer of frozen soil and dead plants that extends some 1, feet meters below the surface. In much of the Arctic, it is frozen year-round. In the southern regions of the Arctic, the surface layer above the permafrost melts during the summer, and this forms bogs and shallow lakes that invite an explosion of animal life.
Insects swarm around the bogs, and millions of migrating birds come to feed on them. With global warming, the fall freeze comes later— in some places recently, not at all —and more of the permafrost is melting in the southern Arctic. Shrubs and spruce that previously couldn't take root on the permafrost now dot the landscape, potentially altering the habitat of the native animals.
Shrubs are getting taller, contributing to declines in the sensitive groups of lichen that caribou and other species depend on for food. Lakes and ponds are evaporating or draining away. Perma Defrost The Arctic's permafrost , the literal foundation for much of the region's unique ecosystem, is deteriorating with the warmer global climate.
Permafrost is a layer of frozen soil and dead plants that extends some meters 1, feet below the surface. In much of the Arctic, it is frozen year-round. In the southern regions of the Arctic, the surface layer above the permafrost melts during the summer, and this forms bogs and shallow lakes that invite an explosion of animal life. Insects swarm around the bogs, and millions of migrating birds come to feed on them. With global warming, the fall freeze comes later—in some places recently, not at all—and more of the permafrost is melting in the southern Arctic.
Shrubs and spruce that previously couldn't take root on the permafrost now dot the landscape, potentially altering the habitat of the native animals. Another major concern is that the melting of the permafrost is contributing to global warming.
The frozen ground contains about one and a half times the amount of carbon already in the atmosphere today, as well as large amounts of methane, another potent greenhouse gas.
Until recently, the tundra acted as a carbon sink , capturing huge amounts of carbon dioxide from the atmosphere as part of photosynthesis. That process helped keep the amount of this greenhouse gas from accumulating in the atmosphere. Today, however, as the permafrost melts and dead plant material decomposes and releases greenhouse gases, the tundra has flipped from a carbon sink to a carbon contributor. That means not only is the planet less capable of preventing greenhouse gases from accumulating, but the tundra is also contributing to their buildup.
Scientists are still learning about what else the permafrost harbors, and what could be released as it thaws. Recently a study found that it is also the largest store of mercury on the planet and could release the toxic heavy metal into the environment, to harmful effect. Mosses, sedges, and lichens are common, while few trees grow in the tundra.
The trees that do manage to grow stay close to the ground so they are insulated by snow during the cold winters. Stories, experiments, projects, and data investigations. Download issues for free. EO Explorer.
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