NASA's Operation IceBridge Completes Eleven Years of Polar Surveys

Narration: Katie Jepson

Transcript:

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Narrator: Operation IceBridge, you may know it from the

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the beautiful photos that pop up in your feed.

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But did you know that IceBridge is the largest polar airborne survey of its kind?

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IceBridge was designed to study annual changes in thickness of sea ice, glaciers, and ice sheets. As well as bridge the

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gap between the ICESat and ICESat-2 polar observing satellites.

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Between 2009 and 2019, IceBridge flew over a thousand

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missions, gathering data that has redefined

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our understanding of the cryosphere.

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So, let’s take a look back at some of the mission milestones from over the years.

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One of the first steps to measure sea ice thickness is to get a handle on the amount of

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snow that accumulates on top of it.

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The IceBridge team pioneered the use of a snow radar instrument to gather the first

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widespread dataset of snow thickness on top of both Arctic and Antarctic sea ice.

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Closer to land,

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the point at which a glacier begins to float is called a grounding line,

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and it’s a very challenging place to measure ice thickness.

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Using two instruments, a radar sounder and a gravimeter,

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the IceBridge team was able to survey hundreds of these complex transition zones,

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enhancing scientists’ understanding of the rapid changes in glacier behavior.

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In 2011, NASA scientists discovered

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a 19-mile long crack across the Pine Island Glacier,

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one of the fastest retreating glaciers in Antarctica.

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The crack measured 260 feet wide and 195 feet deep

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when it was observed.

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Throughout the mission, IceBridge was able to map rifts in ice shelves prior to major

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calving events. And while these events are part of a natural cycle,

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IceBridge’s observations helped scientists better record the changes in calving

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frequency and model how they may be related to a thinning ice shelf.

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The motion of the Antarctic Ice Sheet,

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the largest ice sheet in the world, is heavily influenced by

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the topography of the bedrock underneath.

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In 2013, the British Antarctic Survey used over 25 million measurements

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collected by IceBridge and other projects

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to develop a 3D map of Antarctica’s bedrock topography.

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Called Bedmap-2, it provided unprecedented

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detail of how the continents bedrock shaped the flow of the ice sheet.

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Data collected by IceBridge enabled

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many discoveries in the Arctic as well.

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A team from the University of Bristol used IceBridge’s radar data,

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along with other datasets, to uncover a 400-mile long canyon buried

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under nearly two miles of ice.

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This hidden canyon is longer than any other known on earth, provides a critical clue to modeling how melting ice

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is funneled into the Arctic Ocean.

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Using ice-penetrating radar data collected by IceBridge,

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scientists were able to build the first-ever age map of the layers

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deep inside the Greenland Ice Sheet.

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For the first time, scientists could navigate the history of Greenland’s ice layers,

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extending previously collected ice cores to better understand

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the ice sheet’s history and help build models of its future.

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An international team of scientists

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used decades of NASA data to uncover a massive impact crater

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hiding beneath the Hiawatha Glacier in northwest Greenland.

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At roughly a thousand feet deep and more than 19 miles wide,

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it is potentially one of the youngest large impact craters on Earth.

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Cockpit: "It’s going to happen..5..4..3

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..2..Mark on the overpass 043435 Zulu"

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Narrator: Ice was bridged on April 8, 2019,

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with the direct underflight of the ICESat-2

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satellite over Arctic sea ice.

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For the first time, both ICESat-2 and IceBridge would be taking the same

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elevation measurements of the same ice.

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These mirrored measurements were critical in validating the satellites instruments

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and continue the legacy of IceBridge after the mission was completed.

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Over the course of its 11-year mission, IceBridge

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completed 1056 scientific flights and provided a wellspring of data

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that fueled the publication of more than 660 papers

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and counting.

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The mission provided new insight into the processes driving the changes in the cryosphere,

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helping scientists better understand what we can expect in the future.

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Message Katie Jepson