WEBVTT

00:00:02.970 --> 00:00:06.707
[music playing]

00:00:06.707 --> 00:00:08.242
- Hi, I'm Mishay for
"NASA eClips,"

00:00:08.242 --> 00:00:10.110
and today I'm at
the Virginia Living Museum

00:00:10.110 --> 00:00:11.945
in Newport News, Virginia.

00:00:11.945 --> 00:00:13.947
Today I'll be talking with some
NASA scientists

00:00:13.947 --> 00:00:16.316
to learn more about how
scientists gather information

00:00:16.316 --> 00:00:18.018
about Earth systems.

00:00:18.018 --> 00:00:23.023
[music playing]

00:00:29.096 --> 00:00:30.364
I'm here with Jessica Taylor

00:00:30.364 --> 00:00:32.132
from NASA Langley Research
Center.

00:00:32.132 --> 00:00:34.801
Jessica is an atmospheric
scientist.

00:00:34.801 --> 00:00:36.303
- Hi, Mishay.
It's nice to meet you.

00:00:36.303 --> 00:00:37.905
- It's nice to meet you too.

00:00:37.905 --> 00:00:39.306
- I understand that you want to
learn more about how NASA

00:00:39.306 --> 00:00:41.742
scientists gather information
about our earth.

00:00:41.742 --> 00:00:43.277
- That's right.

00:00:43.277 --> 00:00:45.112
For my science class, I learned
that Earth is a part

00:00:45.112 --> 00:00:46.914
of one big system,
but it also is a part

00:00:46.914 --> 00:00:48.615
of some smaller subsystems.

00:00:48.615 --> 00:00:50.784
But I'm not quite sure how all
that works together.

00:00:50.784 --> 00:00:53.687
- Well, why don't we go inside
and go to cypress swamp

00:00:53.687 --> 00:00:56.256
and I can show you a little more
about how these Earth systems

00:00:56.256 --> 00:00:58.559
interact.

00:00:58.559 --> 00:01:01.562
As you can see, the Earth
really is a complex system.

00:01:01.562 --> 00:01:02.996
Changes in one part
of the subsystem

00:01:02.996 --> 00:01:04.831
can impact the whole planet.

00:01:04.831 --> 00:01:06.266
Scientists study
the Earth system

00:01:06.266 --> 00:01:08.302
by looking at multiple spheres.

00:01:08.302 --> 00:01:11.471
The water here is an example
of the hydrosphere.

00:01:11.471 --> 00:01:15.843
The air that we breathe is an
example of the atmosphere.

00:01:15.843 --> 00:01:17.110
The land that you see here,

00:01:17.110 --> 00:01:19.346
that's an example of
the lithosphere.

00:01:19.346 --> 00:01:20.881
And all of these animals--

00:01:20.881 --> 00:01:23.083
the turtles, the fish,
and the ducks,

00:01:23.083 --> 00:01:26.053
they're all part of
the biosphere, living things.

00:01:26.053 --> 00:01:28.155
And then there's the cryosphere,
ice.

00:01:28.155 --> 00:01:30.324
We can't see that here because
we're in Virginia,

00:01:30.324 --> 00:01:32.226
and it just doesn't get cold
enough here.

00:01:32.226 --> 00:01:33.794
Scientists keep an eye
on these systems

00:01:33.794 --> 00:01:35.762
to make sure they're functioning
as we expect.

00:01:35.762 --> 00:01:37.030
While scientists look at changes

00:01:37.030 --> 00:01:38.465
right here at our Earth's
surface,

00:01:38.465 --> 00:01:40.300
NASA also uses satellites,

00:01:40.300 --> 00:01:42.769
with instruments looking back
down at Earth from space.

00:01:42.769 --> 00:01:44.738
And we use these satellites
to collect data

00:01:44.738 --> 00:01:47.674
for long-term global
perspective.

00:01:47.674 --> 00:01:50.344
- So what kind of tools do you
use to look at those changes?

00:01:50.344 --> 00:01:52.613
- Well, let's find out more by
talking with a friend of mine,

00:01:52.613 --> 00:01:54.047
Dr. Steven Pawson.

00:01:54.047 --> 00:01:56.450
He's at NASA's Goddard
Space Flight Center.

00:01:56.450 --> 00:01:57.751
So let's come right over here,

00:01:57.751 --> 00:01:59.586
and we can call Dr. Pawson
directly.

00:02:02.022 --> 00:02:04.258
[keypad beeping]

00:02:04.258 --> 00:02:05.859
- Hi, Dr. Pawson.

00:02:05.859 --> 00:02:07.561
Jessica and I have already
talked about Earth systems,

00:02:07.561 --> 00:02:09.930
but I don't understand how these
systems affect climate

00:02:09.930 --> 00:02:12.165
or how NASA can track that.

00:02:12.165 --> 00:02:14.101
- Yes, I'm very happy to talk
about that.

00:02:14.101 --> 00:02:15.836
First, what we know about
climate

00:02:15.836 --> 00:02:19.439
is that it includes not only
the temperature of Earth

00:02:19.439 --> 00:02:20.707
but also lots of other things,

00:02:20.707 --> 00:02:23.277
such as the cycles of carbon
and water.

00:02:23.277 --> 00:02:25.078
Now, what does NASA do?

00:02:25.078 --> 00:02:27.648
Because NASA built satellites
that can orbit Earth,

00:02:27.648 --> 00:02:30.417
it means we can see all places
from space.

00:02:30.417 --> 00:02:32.719
This gives us a much bigger view
that we can see

00:02:32.719 --> 00:02:34.321
from the surface alone.

00:02:34.321 --> 00:02:36.456
So the instruments on NASA's
satellites

00:02:36.456 --> 00:02:38.892
help us see the complete Earth
and also measure different parts

00:02:38.892 --> 00:02:40.594
of the climate system.

00:02:40.594 --> 00:02:42.763
- So, Steven, can you explain to
Mishay

00:02:42.763 --> 00:02:45.032
a little more about the tools
that are used

00:02:45.032 --> 00:02:46.266
to gather this kind of data?

00:02:46.266 --> 00:02:48.101
And then once NASA has the data,

00:02:48.101 --> 00:02:51.071
how is that data analyzed
and visualized?

00:02:51.071 --> 00:02:52.806
- So I think what's very
interesting

00:02:52.806 --> 00:02:55.008
is that usually when we're
measuring from space,

00:02:55.008 --> 00:02:56.510
we're actually measuring
the light

00:02:56.510 --> 00:02:58.212
that's coming into
the satellite,

00:02:58.212 --> 00:03:01.014
whether that's light in the
visible spectrum that we can

00:03:01.014 --> 00:03:02.850
or whether it's infrared
or ultraviolet light

00:03:02.850 --> 00:03:04.585
that we can't see,
but it's still part

00:03:04.585 --> 00:03:06.920
of the electromagnetic
spectrum.

00:03:06.920 --> 00:03:08.622
And to make real use
of these data,

00:03:08.622 --> 00:03:10.791
we have to be able to deduce
the quantities

00:03:10.791 --> 00:03:12.125
that we're interested in.

00:03:12.125 --> 00:03:14.428
So we know that if we're looking
for ice,

00:03:14.428 --> 00:03:16.063
then if there's a lot of ice,

00:03:16.063 --> 00:03:17.431
more light will be reflected;

00:03:17.431 --> 00:03:19.066
and if there's not much ice,

00:03:19.066 --> 00:03:20.701
it won't be reflected.

00:03:20.701 --> 00:03:22.703
So in a way that's a relatively
straightforward measurement.

00:03:22.703 --> 00:03:24.605
We can detect if there is ice
there or not.

00:03:24.605 --> 00:03:27.341
But typically, if we're trying
to deduce the temperature

00:03:27.341 --> 00:03:28.942
of the Earth from space,

00:03:28.942 --> 00:03:31.011
then we're looking at a
different part of the spectrum

00:03:31.011 --> 00:03:33.747
and we have to be able to
separate impacts of temperature

00:03:33.747 --> 00:03:36.750
from water vapor and from other
gases in the atmosphere

00:03:36.750 --> 00:03:39.920
and do what we call a retrieval
of that information.

00:03:39.920 --> 00:03:43.123
And a retrieval is really using
a lot of complex physical models

00:03:43.123 --> 00:03:46.460
to try to understand what it is
that we're observing

00:03:46.460 --> 00:03:48.695
and what's causing the change in
the light that we're measuring.

00:03:48.695 --> 00:03:51.899
Typically, the physical models
are mathematical equations,

00:03:51.899 --> 00:03:55.369
but what we actually do is code
them to run on a computer.

00:03:55.369 --> 00:03:58.172
Instead of reading just one
column of the atmosphere,

00:03:58.172 --> 00:04:02.109
we're looking at a grid over
the entire Earth of points,

00:04:02.109 --> 00:04:04.678
and that includes
the atmosphere, the land,

00:04:04.678 --> 00:04:06.180
and the ocean.

00:04:06.180 --> 00:04:09.249
And when we know what the state
is at any one time,

00:04:09.249 --> 00:04:11.151
we can run those models forward
in time,

00:04:11.151 --> 00:04:12.986
using very, very powerful
computers.

00:04:12.986 --> 00:04:15.956
And from those we can deduce
what is going to happen

00:04:15.956 --> 00:04:17.624
in one day or two days.

00:04:17.624 --> 00:04:19.226
For instance, we can make
weather forecasts

00:04:19.226 --> 00:04:20.794
or we can run climate
projections,

00:04:20.794 --> 00:04:24.531
which are running up to about
100 years ahead.

00:04:24.531 --> 00:04:28.302
Using this technique,
we're able to deduce

00:04:28.302 --> 00:04:30.337
a lot of information about
the surface of Earth

00:04:30.337 --> 00:04:32.072
and the atmosphere,

00:04:32.072 --> 00:04:36.376
and even the surface layer
of land and oceans from space.

00:04:36.376 --> 00:04:38.345
- Thank you so much
to Dr. Steven Pawson

00:04:38.345 --> 00:04:39.813
and Jessica Taylor.

00:04:39.813 --> 00:04:41.715
Want to find out more about
Earth systems

00:04:41.715 --> 00:04:44.551
and the work being done by
NASA and other scientists?

00:04:44.551 --> 00:04:45.819
Go to this website.

00:04:45.819 --> 00:04:47.387
That's all for now.

00:04:47.387 --> 00:04:50.657
I'm Mishay, and I'll see you
next time on "NASA eClips."