Both the Arctic (North Pole) and the Antarctic (South Pole) are cold because they don't get any direct sunlight. The Sun is always low on the horizon, even in the middle of summer. In winter, the Sun is so far below the horizon that it doesn't come up at all for months at a time. A misconception taught and understood by many is that the poles are in total darkness when they are tilted away from the sun. It does get dark but the darkest days occur at Winter Solstice, December 21, for the North Pole and June 21st for the South Pole. Often, "night" is simply considered to be when the sun is beneath the horizon, as if twilight didn't exist. Twilight glows across the sky to some extent whenever the sun's upper rim is less than 18-degrees below the horizon. This bright twilight is like here in Utah, its the period of time that its nearly dark, but not entirely dark and drivers need to turn their headlights on. In the North Pole complete darkness sets on November 13th and ends January 29th. At this time twilight appears again. So, technically speaking total darkness at the North Pole is only 11 weeks, not 6 months. (https://www.livescience.com/32814-arctic-daylight-darkness-myth-equinox.html) Let's see if we can see what kind of twilight and darkness is at the North and South Pole..... Twilight in Norway. Sunset at the North Pole. Norway Twilight at the ceremonial South Pole. South Pole Darkness at South Pole Darkness at the South Pole and the Aurora Australis. Darkness at North Pole Nuclear Ice Breaking Ship at the North Pole during the total dark days.
Now you get a feeling for why the poles are so cold and frozen. With hardly any light hitting the top and bottom of our planet, the ice has little time to melt and continues to build up each year. Our climate may be changing, warming because of greenhouse gases in the atmosphere, but the fact that our Sun's light is so spread out by the time it reaches the poles, guarantees the poles will remain cold for a long time.
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Mrs. TaylorI love science! Everything about the world is interesting and never boring. I love to study plants, animals, insects, and people. My favorite subjects are my students who are the most unique organisms on the planet! Categories |