Deviation Actions
Tundra
Barren tundra lands are home to hardy flora and fauna and are one of the Earth's coldest, harshest biomes.
An icy expanse of Arctic Ocean surrounds the snow-flecked bluffs of Beechey Island in the Northwest Territories of Canada. The Arctic is the smallest and shallowest of the world's five oceans.
Photograph by Emory Kristoff
The midnight Arctic sun never strays from the horizon in this time-exposed shot of Nunavut's Baffin Island. Some parts of Nunavut endure 24 hours of light from late April until late August and 24 hours of darkness from late October until mid-February.
Photograph by John Dunn
Ice floes drift across the Canada Basin, painted gold by the setting sun. Located just north of Canada's Northwest Territories, the Canada Basin's geothermal-heated waters reach depths of more than 9,186 feet (2,800 meters).
Photograph by Paul Nicklen
The icy coast of Alaska's Little Diomede Island reflects the cool lavender light of the Arctic sun. Big and Little Diomede Island are just two miles (three kilometers) apart but are owned by different countries: Russia and the United States, respectively.
Photograph by Ira BlockTundras are among Earth's coldest, harshest biomes. Tundra ecosystems are treeless regions found in the Arctic and on the tops of mountains, where the climate is cold and windy and rainfall is scant. Tundra lands are snow-covered for much of the year, until summer brings a burst of wildflowers.
Plants and Animals in Tundras
The Arctic tundra, where the average temperature is 10 to 20 degrees Fahrenheit (-12 to -6 degrees Celsius), supports a variety of animal species, including Arctic foxes, polar bears, gray wolves, caribou, snow geese and musk-oxen. The summer growing season is just 50 to 60 days, when the sun shines 24 hours a day.
The few 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.
Impact of Climate Change on Tundras
This map shows the regions of the world where tundras can be found. Tundras are often found near permanent ice sheets where, during summer, the ice and snow recede to expose the ground and allow vegetation to grow.
Data courtesy World Wildlife Fund
It is the Arctic's permafrost that is the foundation for much of the region's unique ecosystem, and it is the permafrost that is deteriorating with the warmer global climate. Permafrost is a layer of frozen soil and dead plants that extends some 1,476 feet (450 meters) under 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 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. Estimates suggest that about 14 percent of the Earth’s carbon is tied up in the permafrost. Until recently, the tundra acted as a carbon sink and captured huge amounts of carbon dioxide from the atmosphere as part of photosynthesis. This 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 CO2, the tundra has flipped from a carbon sink to a carbon contributor. This means not only is the planet is less capable of preventing greenhouse gases from accumulating, but the tundra is also contributing to their buildup.
Saved from www.nationalgeographic.com/
