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Ice.

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You might know that ice plays significant part in climate change. 

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But what about how scientists study it?

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The first satellite solely dedicated to collecting information on the world’s ice 

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was the Ice, Cloud, and land Elevation Satellite, better known

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as ICESat. But back in 2009, 

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ICESat was decommissioned, and ICESat-2 didn’t launch until nearly

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a decade later in 2018. So how did we study ice in the meantime? 

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Enter Operation IceBridge.

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NASA’s Operation IceBridge was created to quite literally bridge

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the gap in data collection between satellites, and it’s the largest

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airborne survey of Earth's polar ice ever. 

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After 11 years of providing invaluable yearly measurements from both poles, 

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surveying glaciers, ice sheets, and sea ice, most of IceBridge came to 

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a close. However, one small part of the mission

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still continues in 2020 -- Operation IceBridge

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Alaska. A team of scientists from the University

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of Alaska Fairbanks studies and records the annual changes in Alaska’s

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ice thickness. They do so through a remarkable aircraft. 

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specially retrofitted for science. By shooting a laser

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out of the bottom of the plane that hits the glacier’s surface and bounces back up,

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scientists can measure the surface elevation. And using ice-penetrating

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radar, they can measure the bedrock below the glacier, and come up with

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an estimate of ice thickness. But the field missions in Alaska

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face especially challenging circumstances. In order

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to measure glaciers within data collection lines, the plane must be flown

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very low while navigating around extremely tricky mountain ranges,

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making for some of the most adventurous mission flying around.

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Even the glaciers themselves have proven to be a challenge to scientists. 

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Most glaciers in Alaska are temperate, meaning

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they’re at their melting point from surface to base, and contain large pockets

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of water within the ice. Those pools of water muddle the

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radar signals, making it difficult to collect consistent measurements of

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thickness. And these measurements recorded are vital.

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Alaskan glaciers make up only a small percentage of the world’s ice, 

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but they contribute a disproportionately large amount to sea level rise.

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The research and data collection done 

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under Operation IceBridge helps give scientists a closer look at the

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connections between mountain glaciers and global climate change.

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EXPLORE EARTH

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NASA