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[Music, wind and rain sounds]

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[music, wind and rain sounds]

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Scott: Hurricane track

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forecasts have improved quite a bit over the years. I think that's largely due to

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the fact that track is governed by the large scale winds. And larger scales

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tend to be easier to predict. Storm intensity though is much

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more complicated because it depends on a range of scales, all the way from

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those same very large scales down to much smaller scales,

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say, the scale of individual rain bands, and some would even argue down to the

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scale of individual raindrops.

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HS3 uses two of NASA's unmanned Global Hawk aircraft.

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These aircraft are capable at flying at high altitudes above the storm.

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A typical science flight would be about 26 hours,

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that means we can take off from the East Coast of the United States, fly all the way

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out to the Cape Verde Islands off of Africa, fly around for about 4 to 6 hours,

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and then return.

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We're looking at the relative roles of the the environment through which

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the storms move and then also what's happening in the interior of the storms, and

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how those two interact to lead to storm intensification.

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And so we designed the payloads on the Global Hawks

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to really tackle one or the other. So on one

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Global Hawk that we call our Environmental Global Hawk, we have a set of three

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instruments that take measurements of environmental temperature,

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relative humidity, pressure, and wind speed and wind direction.

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On the over-storm aircraft, we have a set of instruments

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that are really geared toward precipitation and winds within the storm.

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The ideal

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storm for us is a storm that comes off Africa, looks promising,

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has a nice interaction potentially with the Saharan Air Layer, moves

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north of the Caribbean Islands and becomes a major hurricane, and then recurves

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and moves northward in the Central Atlantic where

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it's far away from land, but provides us with a good laboratory for getting

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measurements and really understanding the significant storms, which are the major

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hurricanes.
[beeping, thunder sounds]

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