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The reason that we as humans care
about climate change

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is that it affects
not just the temperature,

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but a whole bunch of other things
that we care about.

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It affects soil moisture,

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which in turn affects our ability
to grow the things that we eat.

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It affects cloud cover.

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It affects rainfall patterns.

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It increases drought risk in some regions
and decreases it in other regions.

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Understanding our changing climate
on a planet with incredibly complex

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and interconnected systems
is a massive scientific undertaking.

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And climate scientists like Kate
Marvel are using the data collected

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by satellites from around the world
to improve the power of climate models.

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If we want to make better decisions about

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where we live, understand
the changing impacts of hurricanes

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or improved predictions of fire seasons,
we need evolving climate models.

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We don't have any observations
from the year 2050, from the year 2100,

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but we can use our best knowledge
of physics and chemistry

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and how the Earth system works
in order to look at the impact

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of different emissions
trajectories, different policy scenarios.

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Climate models provide a view
into our future from our globe

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to our own communities.

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As models advance, as they're tasked
with predicting the nature of the weather

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and the clouds over
smaller and smaller scales,

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they're being asked
tougher questions like, Well,

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what kind of clouds are happening
over those small scales and how often

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and how heavily are they raining?

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We expect roughly on really,
really large scales

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climate change is making wet
regions wetter and dry regions drier.

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But at the same time, it's shifting
the circulation of the atmosphere.

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So the locations on a very,

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very large scale of those wet
and dry regions are changing.

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Climate models are composed of
lots of different calculations on the

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different behaviors of our atmosphere,
our land and our oceans.

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To accurately represent the natural world
they need massive amounts

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of satellite data over decades from NASA's
Earth observation

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fleet and its partners around the world.

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Satellites like the Global Precipitation
Measurement Mission

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provide valuable rainfall data

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on daily to seasonal timescales
for the past 20 years.

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And it's that information,
along with a suite of other

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data that go into climate
model development.

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Currently, the GPM microwave imager
radiance data are used to generate

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initial states of NASA climate models
and to guide climate model

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solutions to be close to real states
by applying data assimilation techniques.

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Data assimilation is the process
of combining many different sources of

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Earth observations into models to improve
how we represent the Earth system.

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Assimilating GPM microwave imager data

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improved intensity and locations of storms

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and precipitation
calculated by the climate models.

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And once a climate model is developed,
it's tested over and over because, well...

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All models are wrong,

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but some models are useful,
so they're always going to be incomplete.

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They're always going to be a not exact
representation of the real world.

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But we want to make sure that they are
capturing important aspects of the Earth

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so that we can treat them
as credible going forward.

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Typically, what happens is when you modify
one part of the climate model,

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other parts accidentally change.

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It's kind of like the Whack-A-Mole game.

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By hitting it down, we're improving it,
we're killing the error, we're decreasing

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the problem existing in a model,
but another area pops up.

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And that is why NASA observations
of the Earth from space, the air and

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the ground are critical to understanding
how our Earth system works.

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Observations help improve the modeling
for our future here on Earth,

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with new capabilities
to expand our knowledge.

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NASA is launching satellites
and coordinating missions, like GPM,

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giving us that long term, really accurate
satellite record of what's been going

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on, not just the temperature rising,
but of various aspects

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of the climate changing.

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So precipitation and cloud cover
and soil moisture,

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and a whole bunch of different
climate variables that people care about.

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Continuing key observations of the Earth
is really important

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to see how our atmosphere, land
and oceans are changing over time.

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A long term record,
combined with cutting edge observations

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from the new NASA
Earth System Observatory, will continue

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to push boundaries to better understand
our ever changing Earth.