WEBVTT FILE

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Over the past few days, we've seen a significant amount of actually liquid

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water on the surface that has both accumulated in small ponds and

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probably approaching the size of lakes, especially near the edge of the ice sheet.

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Last spring, flying over the southern Greenland Ice Sheet,

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NASA’s Operation IceBridge witnessed signs

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of the second-earliest onset of surface melt recorded in the 40 years of the satellite record.

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An interesting thing is that the melt season actually in Greenland started

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pretty much end of April beginning of May, which in the grand scheme

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of things is very close to a month earlier than, than average.

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My name is Brooke Medley. I'm the Deputy Project

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Scientist for Operation IceBridge. Last April

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and May, we were actually flying in Greenland out of

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Kangerlussuaq on the NASA P-3. This was

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somewhat of a unique year where we expected

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to be going early enough where we would see the typical

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dry snow conditions. But rather we were met with

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a much different scenario where we saw all these spectacular

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blue ponds of beautiful liquid water just pooling

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on top of the surface. The ice sheet is actually

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experiencing almost an additional month of melt because it

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started so early here, part of it is actually driven by the fact that

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it's very warm right now, but also that there was not a lot of

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snowfall last winter. And so what that means is,

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when the, the snow does melt it very quickly exposes darker

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ice, which can then melt even faster.

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It went from pretty much frozen over at the surface,

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just before the melt started to completely unfrozen

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and the rivers have risen and there's just a significant

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increase in the total amount of water that we just see in general.

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Over the course of 2019,

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there was so much melt that it actually ended up being

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the second-largest meltwater production year

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for the Greenland Ice Sheet since 1980. What does it mean for

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2020 is an excellent question. So what happens

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when you have a an extreme melt year is that it can often impact

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a subsequent season. So it's definitely something we

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were looking for coming into the 2020 season is,

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are we going to be seeing another 2019 because we've

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preconditioned the ice sheet to be more susceptible

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to melt and, and interestingly, right now, 2020 is

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trending along a more normal trajectory for melt.

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That being said, this is still just July and the biggest

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pulse of meltwater from 2019 actually occurred

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at the end of July beginning of August, so there's still a lot of melt

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season left to go. It's actually quite simple

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-- the longer your melt season that means you can just have more time to accumulate more melt

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and the only place for this water to go is into the ocean,

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so it will be driving sea level rise, and Greenland is

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currently, outside of the thermal expansion of the ocean, is

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the largest contributor to global sea level rise.

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EXPLORE EARTH

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NASA