9781422279205

13

Brrrr!

Theaverage temperature inAntarcticawarmsup to–58°F(–5°C) during the summer months—still not exactly balmy weather. The record low temperature for the Arctic is –90°F (–68°C), on a couple of different occasions in parts of Russia. The coldest temperature ever recorded in the United States came at Prospect Creek,Alaska, just above theArctic Circle, in 1971: –80°F (–62°C). The ordinary freezing point of water, of course, is 32 degrees Fahrenheit— above zero. (Thirty-two degrees Fahrenheit is zero degrees Celsius.) So there’s no shortage of ice in the Arctic and the Antarctic! Ice, Ice Baby There’s plenty of ice in the Arctic and Antarctica, but not all ice is created equal.There’s frazil ice, grease ice, pack ice (also called sea ice), annual ice,multiyear ice, glaciers, icebergs, and lots, lots more.Who knew there were so many types of ice? When the surface areas of seawater, like that in the Arctic Ocean, begin to freeze, they form a loose, slushy mixture called frazil ice. It morphs into grease ice, which is still thin and soupy, but sturdier than frazil ice.When grease ice thickens to a more solid version, it is pack ice. Pack ice that melts in the summer and then re-forms in winter is called annual ice. Pack ice that doesn’t completely melt in the summer is called multi-year ice. There are dozens of other types of ice, most of which are re- flected in their name. Anchor ice is attached to the bottom of a sea or river. Brash ice consists of fragments from the wreckage