[music playing]
- Hi, I'm Mishay for "NASA eClips,"
and today I'm at the Virginia Living Museum
in Newport News, Virginia.
Today I'll be talking with some NASA scientists
to learn more about how scientists gather information
about Earth systems.
[music playing]
I'm here with Jessica Taylor
from NASA Langley Research Center.
Jessica is an atmospheric scientist.
- Hi, Mishay. It's nice to meet you.
- It's nice to meet you too.
- I understand that you want to learn more about how NASA
scientists gather information about our earth.
- That's right.
For my science class, I learned that Earth is a part
of one big system, but it also is a part
of some smaller subsystems.
But I'm not quite sure how all that works together.
- Well, why don't we go inside and go to cypress swamp
and I can show you a little more about how these Earth systems
interact.
As you can see, the Earth really is a complex system.
Changes in one part of the subsystem
can impact the whole planet.
Scientists study the Earth system
by looking at multiple spheres.
The water here is an example of the hydrosphere.
The air that we breathe is an example of the atmosphere.
The land that you see here,
that's an example of the lithosphere.
And all of these animals--
the turtles, the fish, and the ducks,
they're all part of the biosphere, living things.
And then there's the cryosphere, ice.
We can't see that here because we're in Virginia,
and it just doesn't get cold enough here.
Scientists keep an eye on these systems
to make sure they're functioning as we expect.
While scientists look at changes
right here at our Earth's surface,
NASA also uses satellites,
with instruments looking back down at Earth from space.
And we use these satellites to collect data
for long-term global perspective.
- So what kind of tools do you use to look at those changes?
- Well, let's find out more by talking with a friend of mine,
Dr. Steven Pawson.
He's at NASA's Goddard Space Flight Center.
So let's come right over here,
and we can call Dr. Pawson directly.
[keypad beeping]
- Hi, Dr. Pawson.
Jessica and I have already talked about Earth systems,
but I don't understand how these systems affect climate
or how NASA can track that.
- Yes, I'm very happy to talk about that.
First, what we know about climate
is that it includes not only the temperature of Earth
but also lots of other things,
such as the cycles of carbon and water.
Now, what does NASA do?
Because NASA built satellites that can orbit Earth,
it means we can see all places from space.
This gives us a much bigger view that we can see
from the surface alone.
So the instruments on NASA's satellites
help us see the complete Earth and also measure different parts
of the climate system.
- So, Steven, can you explain to Mishay
a little more about the tools that are used
to gather this kind of data?
And then once NASA has the data,
how is that data analyzed and visualized?
- So I think what's very interesting
is that usually when we're measuring from space,
we're actually measuring the light
that's coming into the satellite,
whether that's light in the visible spectrum that we can
or whether it's infrared or ultraviolet light
that we can't see, but it's still part
of the electromagnetic spectrum.
And to make real use of these data,
we have to be able to deduce the quantities
that we're interested in.
So we know that if we're looking for ice,
then if there's a lot of ice,
more light will be reflected;
and if there's not much ice,
it won't be reflected.
So in a way that's a relatively straightforward measurement.
We can detect if there is ice there or not.
But typically, if we're trying to deduce the temperature
of the Earth from space,
then we're looking at a different part of the spectrum
and we have to be able to separate impacts of temperature
from water vapor and from other gases in the atmosphere
and do what we call a retrieval of that information.
And a retrieval is really using a lot of complex physical models
to try to understand what it is that we're observing
and what's causing the change in the light that we're measuring.
Typically, the physical models are mathematical equations,
but what we actually do is code them to run on a computer.
Instead of reading just one column of the atmosphere,
we're looking at a grid over the entire Earth of points,
and that includes the atmosphere, the land,
and the ocean.
And when we know what the state is at any one time,
we can run those models forward in time,
using very, very powerful computers.
And from those we can deduce what is going to happen
in one day or two days.
For instance, we can make weather forecasts
or we can run climate projections,
which are running up to about 100 years ahead.
Using this technique, we're able to deduce
a lot of information about the surface of Earth
and the atmosphere,
and even the surface layer of land and oceans from space.
- Thank you so much to Dr. Steven Pawson
and Jessica Taylor.
Want to find out more about Earth systems
and the work being done by NASA and other scientists?
Go to this website.
That's all for now.
I'm Mishay, and I'll see you next time on "NASA eClips."