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[rain drops]

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[natural sound]

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[wind, rain]

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00:00:20,420 --> 00:00:16,370
[water flowing]

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00:00:20,440 --> 00:00:24,440
Dalia: Freshwater is extremely important on Earth. Only three

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00:00:24,460 --> 00:00:28,480
percent of our water is actually in the form of freshwater.

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And only a fraction of that is actually usable

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freshwater on the surface.
Gail: If we don't know what

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00:00:36,600 --> 00:00:40,620
kind of freshwater availability we have, then we may

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have issues in terms of droughts, we might have landslides,

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floods and things like that, and we need to be able to track those

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long term.
Dalia: Understanding how freshwater moves

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through the system is extremely important, both at the local scale, looking at how much water

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we have in our reservoir, to the larger scale, looking at how precipitation

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00:01:00,990 --> 00:01:05,000
moves from ice pack, to the ocean, and then is

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evaporated from there. Sensors

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00:01:09,060 --> 00:01:13,130
on the ground can look at a point source, so we understand how much rain is

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falling at a specific location, but there aren't very many

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gauges around the world that can provide that information for us.

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Arthur: If we were to take all the existing rain gauges in the

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world, they would fit into an area about the size of two

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basketball courts.
[rocket launching]