破冰之旅：北冰洋今昔谈

2004年，综合大洋钻探IODP 302航次在北冰洋的深海钻探发现：五千万年前的北冰洋曾是个亚热带淡水湖泊，沉积物具有优越的生油条件。2007年俄罗斯“和平－1”号深潜器将俄国旗插到北极的四千米深海海底，引起了北冰洋资源归属的国际之争。这些“破冰之旅”是在北冰洋海冰迅速减少的全球变暖背景下进行的，使得“西北航道”开启的前景逐渐逼近，北冰洋的国际竞争正在升温。

Ice Breaking Expeditions: the Present and Past of the Arctic Ocean

In 2004，Integrated Ocean Drilling Program Expedition 302 drilled in the deep-water Arctic Ocean and discovered that the Arctic Ocean was a fresh-water lake with a subtropical climate some 50 million years ago, and its deposits are highly promising in oil production. In 2007, the Russian mini-submarine “Mir-1” planted a Russian flag on the sea bed about 4 km below the North Pole, leading to international competing claims over access to Arctic resources. Both the “ice-breaking expeditions” took place under the background of global warming when the Arctic sea-ice cover is rapidly reducing. In result, the opening of the Northwest Passage is progressively approaching, heating up the international competition in the Arctic Ocean.