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Magruder: So ICESat-2 provides bathymetric measurements, and what that means is that measurements beneath the surface of the water.

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So we can map the topography underwater.

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This is interesting because you might notice the really strong returns from beneath the surface of the water.

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Although this is a pretty shallow area, about ten meters or thirty feet deep, the signal is quite strong.

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Just as strong as from the surface of the water.

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The reason that is is that there's a lot of limestone in the deposits there, and it's highly reflective.

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So ICESat-2 gets a lot of reflected photons back from those laser shots.

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Neuenschwander: In this profile, the vegetation is dominated by

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shrub mopane, which is typically in the two to three meter range, and there's also some mopane

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and acacia trees that typically that are in the four to six meter height range.

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Something that scientists need to understand and quantify is where carbon is being taken up

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and where it is already being stored.

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Because much of the effort related to mapping global biomass has been really focused

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in the tropics where the trees are large and the biomass is high,

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many of these savanna and woodland ecosystems tend to get neglected or are poorly characterized

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in global carbon accounting efforts.

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Gardner: Now one of the unique things about ICESat-2 is it's actually able to see down into

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the valleys of these very steep topography areas where the glaciers are.

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And so there's other instruments, like radar, that aren't able to see the glaciers all the way down in the valleys

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and so ICESat-2 is going to let us measure the changes in mountain glaciers so we can assess how they're responding to changes

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in climate and what potential they have to contribute to both sea level rise in the future

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but also changes in water resources.

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Glaciers in this region have been experiencing rapid rates of thinning

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and that thinning is in response to changes in climate.

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Not only are these glaciers thinning, but as they thin, there's less force pulling them downward.

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And that less force pulling them downward is causing them to actually slow down.

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In high mountain Asia, we actually have glaciers that are thinning and slowing down as they respond to climate.

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