One such satellite, NASA's ICESat, carries a laser altimeter to measure the height of the ice surface.

其中的一颗卫星，美国宇航局的icesat就携带着一个激光高度探测仪来探测冰面的高度。

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Hyperspectral data, scientists have mapped the location of sulfur deposits on the ice surface (red outline).

通过获得的高光谱数据(hyperspectral data)，科学家绘制了冰层表面硫磺沉淀的范围(红色线)。

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Using this hyperspectral data, scientists have mapped the location of sulfur deposits on the ice surface (red outline).

使用这个高光谱数据，科学家已经为冰面硫磺沉积物的位置绘制了地图(红色轮廓)。

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Ice crystals form on the leaf surface.

VOA: special.2010.01.12

The men could not climb out, because the ice surface was nearly vertical, and they huddled together for warmth.

NEWYORKER: Neptune��s Navy

Satellites have long been used to track ice extent (area), but calculating the thickness of the marine floes requires the overflying spacecraft to gauge the difference between the top of the ice surface and the top of the water - a relatively simple calculation then gives the overall volume.

BBC: Launch success for Esa's Cryosat-2 ice mission

The torpedo-shaped instrument gathers data about the difference between the level of the seawater beneath the ice and the surface of the ice itself.

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