What effect has global warming had on the Earth’s polar regions?
Jenny Malliter, Blue Island
The Earth’s polar regions are warming much more rapidly than the rest of the planet. The Arctic Ocean, which includes the North Pole, registered its second lowest ice coverage, 1.44 million square miles, on Sept. 15. Only 2012 had a lower ice minimum, 1.32 million square miles. Declining sea ice creates a feedback loop for global warming. Ice reflects most of the sunlight that strikes it, but ocean water absorbs and re-emits it as heat. More open water leads to more warming. Temperatures at the South Pole (which lies in Antarctica) are rising 1.1 degrees per decade, compared to a rise of only 0.2 degrees per decade worldwide. South Pole temperatures are -58 degrees annually.