No air bubbles were present in the green ice, suggesting that the ice was not formed from the compression of snow but instead from the freezing of seawater.

绿色冰层中不含气泡，这表明了这种冰层是由冻结的海水形成的，而不是凝结压紧的积雪。

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Such ice cores trap gases, bits of dust, and other chemicals that were present in the snow that fell over Greenland for thousands of years and then became compressed into ice.

这些冰芯将气体、尘埃和其他化学物质封存在格陵兰岛数千年来的积雪中，然后被压缩成冰。

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Polynyas are routinely present in these three locations when sea ice is present.The polynyas most likely form where warm ocean currents rise toward the ocean surface.

每当海冰出现时，冰穴惯常在这三个地方发生，这是因为冰穴最可能出现在暖流上升向海面的地方。

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While Radarsat sensors cannot measure the thickness of ice already present, it is able to measure seasonal ice that is produced or lost each year.

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The technology will allow scientists to detect that water and see how much is present under the ice.

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But neutron spectroscopy images have confirmed that the ice is present.

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