Today’s Journal
When you hear the word Arctic, what comes to your mind? Cold, snow, ice? Many people also think of the North Pole. Oh, but there is so much more to the Arctic. Let’s learn a bit more.
As mentioned in a previous journal the Arctic consists of ocean surrounded by land including parts of Canada, Russia, Greenland, Norway, United States, Sweden, Finland, and Iceland. The region is generally ice and snow covered for at least part of the year and covers 18 million square miles (30 million square kilometers)—one sixth of the planet’s landmass—and spans 24 time zones. Wow!
There are actually several definitions of the Arctic region. The Southern extent of the Arctic region is marked by the Arctic Circle at 66° 33′ 44″ or 66.5 degrees N latitude. The Arctic Circle marks the southern extremity of the polar day and night. Anywhere above the Arctic Circle the sun will be completely above the horizon for at least one day per year in the summer and completely below the horizon for at least one day in the winter. At Toolik Field Station, where I will be living, the sun won’t set from May 26 until July 17. Toolik is about 158 miles north of the Arctic Circle. I can’t wait to see the midnight sun!
The Arctic can also be defined by the 10 °C (50 °F) isotherm. An isotherm is an line of equal temperature. So at this line the average temperature for the warmest month of the year (July) is below 10 °C (50 °F). The Arctic isotherm line has shifted north over 100 miles in the last 30 years.
The map below shows both definitions of the Arctic Region. The blue line is the Arctic Circle and the red line is the 10 °C isotherm.
Map of the Arctic Region showing two ways to define the Arctic. The Arctic circle and the 10 degree C isotherm. (courtesy of Wikipedia)
Question to Ponder
Which definition of the Arctic makes the most sense to you? Is one more acurate than the other in your mind? Explain your answer.