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[wind noises]

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[music]

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Hello. My name’s María José Viñas and I am a science writer for NASA.

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I’m here in Greenland, in a town named Kangerlussuaq,

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accompanying a mission called IceBridge, or Puente de Hielo.

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This is the plane we use for our mission,

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a P-3B, which used to be a military plane that was readapted to be used for scientific missions.

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It’s equipped with a series of instruments that I will tell you about later.

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[music, aircraft noise]

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With IceBridge we fly this airplane quite close to the ground,

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at about 450 meters above the surface, and using a series of lasers and radars

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to observe how the ice sheet evolves from year to year.

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[music, aircraft noise]

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We do this twice a year: from October to December we go to Antarctica

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and from March til May we’re here in Greenland, measuring the Arctic ice sheet.

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For example, this morning we’ve flown over Jakobshavn Glacier,

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one of the fastest melting glaciers in the world

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and we’ve measured how high it is this year, and we’ll compare this with data

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from previous years, to find out how much [of the glacier] has disappeared in one year.

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The P-3B carries a laser

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and four types of radar. The laser emits a pulse of light that bounces off the ice surface:

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the time that it takes for the light to return to the receivers installed

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in the body of the plane is indicative of the height of the ice sheet.

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The radars work in a similar way, but they use electromagnetic energy,

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which is able to penetrate the ice sheet and obtain information about its depth and structure.

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Two other instruments onboard the aircraft, called the gravetometer and magnetometer,

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analyze the geologic composition of the ground.

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Scientists study the data obtained during each IceBridge campaign

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and compare it to data from previous years, to calculate how

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the ice sheet changes from year to year.

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Here we are at the Russell Glacier, at the feet of Greenland’s ice sheet

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extending kilometers and kilometers into the interior of Greenland.

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And when you see this immensity is a bit hard to imagine

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disappear one day but that is what is happening right now, it's melting