There are five different types of Arctic Circles. They are all important boundaries of life. They are of interest to curious people. And they are all changing. A globe at the Arktikum in Rovaniemi is showing these important lines of life.
First and foremost is the Arctic Circle. It is one of the five major circles of latitude around the Earth. The famous latitude line is 66 degrees, 33 minutes, and shifting seconds north of the Equator. The Arctic Circle is not set in stone. Since the Earth’s axial tilt fluctuates 2 degrees over periods of 40 000 years the Arctic Circle is constantly heading somewhere. Northbound, as you read by roughly 4 cm per day. The Arctic Circle has one day in the winter when the sun doesn’t rise, and one day in the summer when the sun doesn’t set. This number of days increases the further north you go.
Second is the Arctic tree line. Below the tree line, big trees grow. Above it, only small trees, at best, grow naturally. The cold temperatures of the Arctic make it impossible for large trees to stay sustainable warm and to have roots deep enough to keep it upright. In northern Scandinavia the Arctic Tree Line is some 71 degrees north. Part of the northernmost coastal area of the Kola Peninsula is above the Arctic Tree Line. Eastern Canada has the lowest Arctic Tree Line at 56 degrees north.
Third is permafrost. This is when the water in the soil is freezing at least two years in a row. Only high altitude mountain areas in Scandinavia experience permafrost currently. Areas of Asia and North America above 50 degrees north have permafrost.
Forth is the Arctic Sea Ice at is smallest in September.
Fifth is the Arctic Sea Ice at is largest in March.
To monitor the four latter lines are of great interest
If the Arctic Sea Ice is so small that it is possible to sail the Northeast Passage, it will have a major impact on international shipping. The alternative route of the Suez Canal between Europe and Japan/Asia will then be longer than the one north of Siberia, Russia.
The changes in edges of the Arctic Sea Ice may put the Arctic center stage of world trade. However, a climate change can also be the brinkmanship of an ecological disaster. A small change can set of a chain reaction towards a different environment.
The Arctic is a place where small differences can lead to big changes. The limited resources of energy make life more vulnerable. If life is destroyed, for instance, by pollution, it takes longer to recover, get healthy and be able to reproduce again.
After Chernobyl the lichens/moss eaten by the reindeer during the winter was very radioactive. The “plant” absorbs all it can, including nuclear downfall, and the reindeer got an unhealthy dose of dangerous atoms.
The Polar Bear is lost without the Arctic Sea Ice. Instead of promenading on the ice it must combust in the water to the next prey. Tired Polar Bears are already washing ashore more frequently than before.
When the environment is changing, it is in the Arctic it changes first. Arktikum is on top of it.