[00:00.00]It was the promise of wealth that first drew European powers to look for a westward route to Asia.[00:06.78]It was wealth rather than the idea of a New World that drove Columbus and other Europeans to search for a western route to China and Japan.[00:16.98]However, they soon realized that the North American continent was a barrier to progress.[00:23.78]So, they began to search for a way around the northern edge of the continent, a Northwest Passage that would link the Atlantic to the Pacific.[00:33.28]For the next 500 years, they nudged their ships through the Arctic waters, looking for the Northwest Passage.
[00:41.78]In the sixteenth century, the Spanish, Portuguese, French, and English all sent expeditions to the northern shores of North America.[00:52.68]They were all driven back by the ice.[00:55.28] The Englishman Martin Frobisher spent several years exploring what is now Canada and searching for wealth in the Arctic.[01:04.78]He made three voyages in search of the Northwest Passage, and he did reach the mouth of the passage, but stopped when he found what he thought was gold. [01:16.28]This “gold” turned out to be iron ore. [01:19.78]In 1607, Henry Hudson began his exploration of the Canadian Arctic.[01:26.78] He discovered the bay that later became Hudson Bay, but the voyage ended in tragedy when the crew rebelled. [01:35.38]The Northwest Passage wasn’t crossed until almost 300 years later, when a Norwegian explorer completed the trip in three years.
[01:46.28]The Northwest Passage is actually a number of possible routes through a deadly maze of sea ice, narrow straits, and oddly shaped islands. [01:56.98]Today, icebreakers can follow the passage with ease, but to attempt it without this technology still requires a great deal of courage. [02:07.28]Depending on ice conditions, one route might be open while another is blocked. [02:13.28]The passage changes from year to year, and even from week to week.
[02:19.28]In the summer of 2000, a Canadian Mountie took a large patrol boat into the heart of the Northwest Passage.[02:27.68] He expected to encounter ice, but to his surprise, there were no bergs, no growlers, and no pancake ice.[02:37.28] In fact, he found no ice at all. [02:40.28]For the past few summers now, vast stretches of the Northwest Passage have been free of ice.[02:47.28] The departure of the ice is the result of natural, long-term atmospheric patterns that have warmed the Arctic in recent decades and also of the heating of the planet by greenhouse gases.
[03:01.48]In the Arctic, temperatures have risen 3 to 4 degrees. [03:06.48]That small difference has changed the landscape for thousands of miles. [03:11.48]The ice has disappeared at a rate of about 3 percent each decade since the 1970s, and ice sheets that used to be ten feet thick are now less than six feet from top to bottom.[03:26.08]Climate experts now predict that, in 50 years or less, the passage will be free of ice throughout the summer.[03:34.48]Canadian officials say it’s only a matter of time before all kinds of ships—everything from supertankers to sailboats-—will start crossing these once impassable waters.
[03:47.68]There are potential consequences to shipping in the passage. [03:52.18]Ships could disrupt the polar bears and bowhead whales that live there.[03:57.18]There could be an increase in the smuggling of polar bear hides and walrus tusks. [04:03.48]An increase in the number of tourists could mean an increase in the amount of trash they leave behind.[04:10.48]The biggest concern, however, is the threat of an oil spill from a supertanker. [04:16.40]An oil spill would damage this pristine region and be extremely difficult to clean up.
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