[Music, wind and rain sounds]
[music, wind and rain sounds]
Scott: Hurricane track
forecasts have improved quite a bit over the years. I think that's largely due to
the fact that track is governed by the large scale winds. And larger scales
tend to be easier to predict. Storm intensity though is much
more complicated because it depends on a range of scales, all the way from
those same very large scales down to much smaller scales,
say, the scale of individual rain bands, and some would even argue down to the
scale of individual raindrops.
HS3 uses two of NASA's unmanned Global Hawk aircraft.
These aircraft are capable at flying at high altitudes above the storm.
A typical science flight would be about 26 hours,
that means we can take off from the East Coast of the United States, fly all the way
out to the Cape Verde Islands off of Africa, fly around for about 4 to 6 hours,
and then return.
We're looking at the relative roles of the the environment through which
the storms move and then also what's happening in the interior of the storms, and
how those two interact to lead to storm intensification.
And so we designed the payloads on the Global Hawks
to really tackle one or the other. So on one
Global Hawk that we call our Environmental Global Hawk, we have a set of three
instruments that take measurements of environmental temperature,
relative humidity, pressure, and wind speed and wind direction.
On the over-storm aircraft, we have a set of instruments
that are really geared toward precipitation and winds within the storm.
The ideal
storm for us is a storm that comes off Africa, looks promising,
has a nice interaction potentially with the Saharan Air Layer, moves
north of the Caribbean Islands and becomes a major hurricane, and then recurves
and moves northward in the Central Atlantic where
it's far away from land, but provides us with a good laboratory for getting
measurements and really understanding the significant storms, which are the major
hurricanes. [beeping, thunder sounds]