Arctic Landscapes
During the summer when the snow cover melts away, a geologist’s dream is revealed. There is little vegetation in most of the Arctic compared with temperate zones, so the rocks and landforms are often completely exposed. Here we look at some of the Arctic landscapes you’ll discover on your trip to the Arctic.
Ice Caps and Glaciers
Outside Antarctica, Greenland has the second largest ice cap in the world. After that, look to Nordauslandet in Svalbard. Icecaps are phenomenal accumulations of ice that developed from the deposition of snow. After hundreds of years of snowfalls that fail to melt during the summer, the accumulation is so great that the sheer weight of the snow compresses the crystals into ice. The pressure causes the crystals to melt and reform as ice crystals to form huge deposits of ice.
Glaciers are similar to ice caps. They form in the same way, except that in glaciers the flowing ice is channelled into valleys and becomes discrete streams. Some glaciers (especially in Greenland and Svalbard) are simply fingers of ice flowing down valleys from the ice cap centred in the highlands above.
As glaciers retreated with the warming trend since the last Ice Age, they have revealed a striking landscape. The melting ice raised the sea level. Glaciers scraped away all the soil and living things, so as they retreat they expose a landscape bereft of plants. Many of the barren landscapes we see in the Arctic are actually a combination of the cold climate making life difficult and the fact that there is a slow recovery from being scraped completely bare by nearby glaciers or an icecap.
The Arctic Tundra
The term tundra comes through Russian and the Kildin Sami word for ‘uplands’ or ‘treeless mountain track’. In physical geography, tundra is a biome where tree growth is hindered by low temperatures and short growing seasons.
The ecological boundary region, also known as the ecotone, between the tundra and the forest is known as the tree line or timberline and is composed of dwarf shrubs, sedges, grasses, mosses and lichens. Scattered trees grow in some tundras.
The soil in the Arctic tundra is frozen from 10 to 35 inches down, so it is impossible for trees to grow there. Low growing plants such as moss, heath and lichen seem to be all that the bare and rocky land can support. However, in the summer months when the temperature rises, the top layer of permafrost melts leaving the landscape very soggy. This is due to the fact that while rainfall is low (6-10 inches per year), the ground below is frozen and so the water cannot sink any lower.
The tundra becomes covered in marshes, lakes, bogs and streams with daytime temperatures sitting at around 12°C. The tundra is a very windy place and in terms of precipitation, it is desert-like. This leads to a natural pattern of accumulation of fuel and wildfire, varying with the terrain and nature of the vegetation.
The biodiversity in the Arctic tundra is low, with only 1,700 species of vascular plants and only 48 land mammals found, although millions of birds migrate there each year for the summer marshes. Arctic tundras are sometimes the subject of habitat conservation programs.
