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hundreds of miles above us a fleet of

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NASA spacecraft constantly scans the

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earth one of these has dramatically

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improved our ability to study severe

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weather trim the tropical rainfall

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measuring mission observes weather

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systems with the world's only

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space-based precipitation radar trim

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peers down through clouds revealing

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their internal structure using trim

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measurements scientists identified a

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dramatic feature in the structure of

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hurricane Bonnie towering rain clouds

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close to the eye wall nearly reached the

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stratosphere these structures called hot

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towers extended higher than commercial

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jets fly research into these

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observations has led scientists to new

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insights about hurricanes let's look at

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the role hot towers play in hurricanes

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a hurricane's eye is an intense

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low-pressure system near the ocean's

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surface air spirals inward in an attempt

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to fill the low-pressure region as air

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nears the eye it rises rapidly until

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forced outward at the barrier formed by

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the warm tropopause the net effect is a

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cycle of air moving inward near the

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ocean's surface

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upward at the eye wall and outward at

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high altitudes the air picks up energy

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from warm ocean water through

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evaporation this warm moist air rises in

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the eyewall and releases its energy

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through condensation sustaining the

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hurricane hot towers act like Express

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elevators accelerating the movement of

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energy into high-altitude clouds this

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energy boost tends to strengthen the

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hurricane

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what causes these hot towers to form

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there's a big difference in wind speeds

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between the fierce eyewall and the

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relatively calm winds inside the eye

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these rapid changes in wind speeds

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caused instabilities that can spin up

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intense vortices just inside the eye

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wall near the surface air spiraling

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inward collides with these vortices

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forcing the air upwards creating an

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updraft a very strong updraft in the eye

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wall carries moisture much higher than

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normal

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creating a hot Tower high resolution

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computer simulations of hurricanes show

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the formation of hot towers in this

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simulation of hurricane Bonnie hot

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towers are clearly visible the arrows

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show winds swirling near the surface

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where energy is picked up from the warm

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ocean some of this air moves into the

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hot Tower and rises rapidly boosting the

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hurricane strength but it's more

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complicated than that

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because hot towers move with the

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hurricane and there are often multiple

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updrafts when air passes into a hot

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tower it rapidly rises higher conditions

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are more favorable for vortices to form

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updrafts on one side of the hurricane

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because wind shear amplifies colliding

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winds in that area when shear causes

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these updrafts to weaken in other areas

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of the eye vortices can also pump eye

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energy air from the eye into the eye

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wall

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boosting the strength of the updrafts

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and intensifying the hurricane

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scientists have confirmed a connection

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between hot towers and hurricane

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intensification but forecasting

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intensification remains a difficult

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problem combining satellite observations

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with supercomputer simulations provides