WEBVTT FILE

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VO: Launched from Japan on February 27,

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2014. the NASA/JAXA Global Precipitation Measurement mission. or GPM.

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has changed the way we see precipitation. It has

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provided unprecedented three-dimensional views of everything from

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light rain to intense thunderstorms. To mark its five years, we’re looking

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back at five big moments in GPM’s history of observing storms.

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[Music]

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VO: Not long after its launch in 2014, the GPM Core

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satellite captured Super Typhoon Vongfong as it headed for Japan.

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Braun: Super Typhoon Vongfong was one of the first Category 5

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intensity cyclones that GPM was able to observe.
VO: The radar

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data revealed a clear eyewall with bands of rain encircling it, forming a

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secondary eyewall. GPM was able to observe Vongfong as it

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weakened.
Braun: So the reason that Vongfong was weakening at this time

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is what we refer to as an eyewall replacement cycle. So those bands outside

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of the eyewall, forming a circle. They essentially cut off the inflow to

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the storm. [Music]

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VO: Hurricane Harvey slammed into Texas and

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Louisiana in August 2017, dumping feet of rain,

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making it the wettest tropical cyclone on record in the United States.

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GPM was able to see the full structure of the hurricane beyond

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the reach of ground-based radars.
Huffman: As Harvey perched over Houston,

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it became highly asymmetric with a large area of rainfall to the north

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and almost no rainfall to the south.
VO: The GPM mission was able to observe

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the historic rainfall estimates over land and ocean, shedding light

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on the structure and magnitude of the storm’s impacts.

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[Music]

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VO: Later in the 2017 Atlantic Hurricane season, GPM was able to see

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the evolution of Hurricane Ophelia.
Braun: What was interesting about Ophelia

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was the fact that it formed sort of from a decaying extratropical frontal system,

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what we call a tropical transition, going from an extratropical system to a tropical

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one. It managed to intensify up to a Category 3

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hurricane in the eastern Atlantic, and this was the farthest east that we’ve had a storm

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of that intensity in the satellite record.

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VO: Later, Ophelia raced off to the northeast, bringing severe winds to the United Kingdom

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and Ireland. [Music]

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VO: On January 4, 2018, a large snowstorm

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rapidly intensified as it moved from the southeastern U.S. up

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the east coast.
Braun: In fact it intensified so rapidly in terms of the drop of

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pressure at the center it was called a “bomb cyclone” and intensified about as

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much as you’d see with an intense hurricane.
VO: GPM clearly depicted

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the transition from rain to snow, shown here as the rain layer

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in green, yellow and red becomes shallower and thinner as it progresses

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northward into snow, show in blue.

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[Music]
VO: The GPM mission

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joins together data from an international satellites to create a

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global picture of precipitation in the Integrated Multi-satellitE

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Retrievals for GPM, or IMERG for short.
Huffman: The great thing about

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IMERG is that the fine scale, in space and time, allows

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you to really see the details, and they flow smoothly from image to the next.

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When you look at this particular week of IMERG, you see some very general patterns:

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You see the high precipitation in the tropics, lower

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precipitation to the north and south of that, and then the storm tracks in midlatitudes.

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VO: For five years, GPM data has advanced our understanding

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of how hurricanes form and intensify, demonstrated how individual

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raindrops are distributed inside storms, and produced

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unparalleled global coverage of precipitation across land and sea.

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[beeping]

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[beeping]