WEBVTT FILE

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[guitar strumming] >>Singing: ICESat

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launched 11 years ago, measuring

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ice, glaciers and snow. Lasers

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housed in a device called "GLAS", observed the Earth

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and sent the data fast. Lasers bounced off the

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polar sector, mapping the Earth with a

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photon collector. Lasers captured both width

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and depth, so we can better study the polar

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breadth. Using our laser technology,

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results in 3D cartography.

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Using our laser technology, we can

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do accurate topography.

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>>Anna: As the global sea level continues to rise, it becomes more and more

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necessary to map how much land ice has melted. But

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how do we map such a big area with any accuracy? The answer

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is lasers. >>Geof: Photos show the changes

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in the surface area of ice, but don't show depth. Lasers can measure

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topography to within an inch. Because of that precision and speed, laser ranging instruments

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are in use to measure the surface topography of the ice and study how much ice has been

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lost. >>Anna:  NASA measure two types of ice. Ice on land,

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and sea ice. Ice sheets and glaciers found on land, like

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Greenland and Antarctica, are formed as snow accumulates

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and is compacted into ice. Sea ice on the other hand, is frozen

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sea water found floating in the Arctic Ocean and offshore of Antarctica.

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>>Geof: IceBridge flights over the ocean near Greenland allow

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researchers to measure the height differences between open water and sea ice,

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which is key to determining the ice thickness. >>Anna: ICESat-2 will measure elevation

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across Earth's entire surface, including vegetation

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and oceans, but with a focus on change in the frozen areas of

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the planet where scientists have observed dramatic impacts on

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climate change. ICESat-2 will be launched in the near future.

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Until then, follow NASA's mapping missions. >>Singing: 2010

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was the end of the mission. IceBridge

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and LVIS flew into position. Crisscrossing

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grids across the ice, measuring once,

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measuring twice. ICESat-2 in the

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next few years, will launch to measure

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new frontiers. ICESat's laser

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technology, reveals our hidden

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geography. Using our laser technology,

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results in 3D cartography.

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Using our laser technology,

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we can do accurate topography.

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[guitar strumming]

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[guitar strumming]

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[final guitar strum]