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Through rain and snow,

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hurricane, typhoon and monsoon,

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flash flood and bomb cyclone,

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for ten years, the joint NASA-JAXA Global
Precipitation Measurement mission

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has measured a lot of water.

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[launch countdown]

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GPM’s Core Observatory

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satellite launched from Tanegashima Space Center
in Japan in early 2014,

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becoming the first satellite
to be able to see through the clouds and measure

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liquid and frozen precipitation from the Equator
to polar regions

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using a radar.

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Freilich: GPM will give us a much better picture of

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of rain and snow falling across our planet.

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Knowing when, where and how much it rains or snows

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will improve our understanding of Earth’s weather and climate cycles.

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Now, in its 10th year of operation,

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we look at ten
events brought to light by this groundbreaking mission.

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In its first year,

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the GPM Core Observatory satellite caught
the heavy rains of the Indian monsoon.

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The monsoon is a seasonal wind and rain pattern

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that can account for up
to 60% of the region's yearly rainfall.

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GPM, allowed us to see precipitating systems
like monsoons

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as a whole, over both land and ocean.

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These satellite data allow researchers to study

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the variability of the monsoon,
as well as how they impact agriculture,

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flooding and landslides in the region.

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In 2015, Tropical Cyclone Kilo slowly

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meandered across the Pacific Ocean for 21 days.

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Because of its long lifespan,

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Kilo created a kind of open ocean laboratory
for the mission to study

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the development of the tropical cyclone
in a way only possible with a global satellite.

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Kilo was so long-running that GPM caught it six times,

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and as both a hurricane and a typhoon
after it crossed

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the International Dateline.

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In September 2016,

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Matthew became the first Category 5
hurricane in almost ten years.

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It strengthened from a Category 1 to a 5 in less than 24 hours,

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leaving a wake of destruction in its path.

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As Matthew traveled through the Caribbean,

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data from GPM and a suite of other satellites
allowed researchers

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to create a multidimensional picture
of the hurricane

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in order to study the complex
atmospheric interactions.

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Less than a year later, Hurricane

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Harvey became a Category 4 as it made landfall in Texas.

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Soon after, Harvey quickly lost speed and slowly
inched up the coast, resulting

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in a record breaking amount of rainfall,
topping four feet in some areas.

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GPM was able to track Harvey and the ensuing
flooding because of its product called IMERG,

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The Integrated Multi-SatellitE Retrievals for GPM.

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IMERG combines information from whatever
group of satellites is operating in Earth orbit

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at any given time, and estimates
precipitation over the entire globe.

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This way, no matter where the GPM Core satellite
is, NASA can track the impact

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of precipitation systems
and provide half-hourly data to local

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and regional agencies.

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It isn't just for rain.

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In fact, GPM became the first NASA satellite

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to measure the full range of light
and heavy rain and falling snow.

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In January 2018, GPM observed

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a rapidly intensifying, or bomb, cyclone,

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which is marked by an extreme drop
in central pressure of the system.

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The radiometer and radar instruments
on the GPM Core Observatory

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allow it to see inside the storm and observe
the frozen precipitation high atop the clouds.

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It can measure, layer by layer,

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the size and distribution of snow particles,

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which can help improve the numerical weather
forecasts of snowfall.

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A Category 5,

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Hurricane Dorian became the most intense tropical cyclone
to hit the Bahamas.

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As it churned northward toward Florida,

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GPM observed an important event
in hurricane evolution:

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an eyewall replacement cycle.

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Here, the initial compact, more intense eyewall
is replaced by a broader eyewall,

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robbing the inner eyewall of moisture and angular
momentum,

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resulting in a weakened storm.

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Predicting eyewall replacement cycles
is difficult for forecast models,

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and detailed data from GPM

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can improve the accuracy of
those forecasts in time.

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Hurricane Laura was the strongest hurricane
to make landfall in Louisiana in over 50 years.

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To study it closely, the GPM Core Observatory's
instruments were able to quantify

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and compare
the distribution of precipitation drop sizes.

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It sounds like too fine a detail,

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but drop size distribution can
tell researchers how droplets

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are colliding and coalescing within the storm
before, during and after landfall.

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This close look at the microphysical environment can help

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improve numerical weather forecasts and complex
climate models.

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GPM can show more than single storms.

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It can cover precipitation over years,
showing us

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longer term phenomena, like El Niño and La Niña.

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These large-scale climate patterns in the
Pacific Ocean can affect weather worldwide.

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Huffman: We need the long-term record
in order to know how

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what's happening now is comparing
to the averages and previous extremes.

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Basically, what's the climate?

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These data are really important for telling us
whether we should expect

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variations such as we're seeing,
or whether perhaps they're new extremes.

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A big part of the GPM

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story is seeing the extremes, both near and far.

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Early 2022 brought Australia's

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worst recorded flooding disasters.

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With IMERG, GPM was able to track and measure
the heavy and persistent rainfall

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from a series of storms that battered
the northwest and east of Australia.

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Providing half-hourly rainfall estimates for
agencies and resource managers around the globe

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has revolutionized
the tools to help with floods, droughts,

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agriculture and disease outbreaks.

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For five weeks, GPM tracked Tropical Cyclone Freddy,

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the longest-lived tropical cyclone on record ever.

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Freddy began over the waters between

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Indonesia and Australia,
and slowly progressed toward eastern Africa,

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causing flooding and destruction
in Madagascar and Mozambique.

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Over the course of the storm’s history, IMERG
revealed a variety of rainfall features

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and trends that relate closely to the variations
in Freddy's intensity.

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For instance, being able to analyze the surface
rainfall intensity and where it occurs

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relative to the storm’s center is valuable
for studying the evolution of tropical cyclones.

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When it comes to climate, what is normal?

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That's kind of a big question,
but providing the best picture

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of what's actually happening is climatology.

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And GPM has made big strides in defining

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the annual cycle of precipitation climatology.

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GPM isn't alone.

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It stands on the shoulders of its predecessor, TRMM,

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the Tropical Rainfall Measuring Mission.

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[launch commentary]

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With TRMM’s launch in 1997, developing

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a fine-scale global precipitation record, began in earnest.

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And while TRMM lasted until 2015,

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it built the foundation of that long record.

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Today, GPM not only has added another decade of data,

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but reanalyzed TRMM’s data with modern algorithms.

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This long and growing record
gives climate researchers

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a good estimate of what their models and results
should reveal in the current era.

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As we continue to

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see climate change impact our seasons,
our regions and towns and our livelihoods,

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we want to know how rain and snowfall
will change, where extreme weather will occur,

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and how often.

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The data from GPM continues

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to help researchers
build on a long record of past precipitation

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in order to set the stage
for understanding the future.