Oh, hey.
Sorry, just admiring my a makeshift ICESat-2 hat.
Hi, my name is Brian Campbell and I am the Trees science lead for the NASA GLOBE Observer
I work at the NASA Wallops Flight Facility. Okay, right there. And that's in Wallops Island, Virginia.
That's what I'm gonna talk to you about today. I'm going to talk to you about how you can actually look at data.
from ICESat-2, you know, while you're at home.
Okay, so it's very easy to do.
First, I'm going to show you a little bit about ICESat-2, which stands for Ice, Cloud and land Elevation Satellite.
So let me put on my fancy protective eyewear, all right, because I'm going to be using a laser.
Alright, so ICESat-2. Since ice is in the name, you definitely know that it has something to do with ice.
So here we have some ice, all right.
The laser is ICESat-2. What ICESat-2 does from hundreds of miles above the Earth's surface
It fires off laser pulses 10,000 times per second.
And when it does this we can calculate the time it takes the laser pulses, or photons
to leave the satellite, hit the Earth's surface and come back to the satellite.
By doing that, we can measure the height of things on Earth like ice, you know, the ice sheets of Greenland and Antarctica.
We can also measure things like trees. Trees have height and elevation.
This is an old Christmas tree that I found in the shed a few days ago. Perfect for this.
Think of ICESat-2 again, as it's traveling across the Earth, okay,
it's bouncing off the tree canopy and it's measuring the height of this tree and the canopy from space.
by counting these laser photons and how long they took to leave the satellite, hit the Earth's surface and come back again.
We do that repeatedly because with NASA Earth science satellite missions, we really want to focus on the change over time,
how things are changing over time on our planet. And ICESat-2 is one of the satellites that helps us do that.
Because it can measure the height of basically anything on the planet.
So let me take this off a second.
I'm going to show you a little bit about ICESat-2 right now. Let me share my screen here for a second.
Brian Campbell: Alright, so I said to is a laser altimeter and space. It has an instrument on a colon Atlas. The Airborne Topographic sorry the advanced topographic laser altimeter system. Okay.
ICESat-2 is a laser altimeter in space. It has an instrument on it called ATLAS.
The Airborne Topographic, sorry, the Advanced Topographic Laser Altimeter System. Okay.
As it's firing these laser pulses to the Earth, it's also collecting the photons that bounce off the Earth's `surface and come back.
And by doing that, as I mentioned, we can measure the height of things over time and see how things are changing now.
What we're going to focus on today are trees and how we can actually look at this data,
how you can be a researcher and look at this data from anywhere in the world.
Have you ever wanted to look at satellite data like a researcher does?
You can now! We have an awesome tool in partnership with the National Snow and Ice Data Center in Colorado.
To actually look at the Open Altimetry data. So let's go ahead and take a look at that data right now.
Now, you should be able to see the website.
OpenAltimetry allows you to go to ICESat-2 data, we're going to click on this little
red section here, little red button and it's going to open this map up. Might be a little slow because there's lots of data to pop up.
So what you're actually looking at here is the ICESat-2 orbit tracks.
Okay, exit that. All these green lines are ICESat-2 orbit tracks and the green dots are photons that took an elevation measurement.
You can go to anywhere on the planet to see if ICESat-2 hit your area.
It doesn't look like a lot of orbit tracks right here, but check this out, I'm going to zoom in.
One of my favorite places to visit is Key West. I live in Maryland up here, okay. I'm going to go to Key West.
So let's zoom in to Key West a little bit.
Sometimes it takes a little while because there's lots of stuff loading.
What you're going to see, you're gonna see all these red lines pop up.
These are all orbit tracks of ICESat-2.
What's cool about this is, if I zoom in to Key West, all right, and I happen to know where Key West is, so here is Key West.
And once again, it might take a second to render you know your location that you're looking for,
We're going to zoom in just a little more. There's Key West right there that popped up.
All right, that's Key West. You can see all of a sudden, there's lots of houses and streets and trees.
Lots of ocean, of course, because it's right there on the Atlantic Ocean and the Gulf of Mexico.
What you can do is click on this red line and all these dates will pop up. This will tell you when ICESat-2 was close.
Let's go here to 12/10, yeah that looks good. So exit out of here.
All these dots that popped up are photons that left the satellite, hit the Earth's surface and came back again.
You can go up here to the top left where it says "select a region," we're going to select the region, and then
if you find where there's some cool trees, you can draw a little rectangle all right, like this.
Then it'll ask you if you want to view the elevation profile, which you can, so another site will pop up.
And it'll show you the whole surface elevation graph, but what we want to really focus on these canopy heights.
Each one of these photons represents the canopy height that ICESat-2 took.
Now, ICESat-2, when the photons hit the ground that creates about a 13 meter diameter footprint on the ground.
Where it's taking canopy heights in that 13 meter footprint.
So within this first one, we see that the canopy heights are about 7.16 meters
then the second one 6.80 meters, and then the last one here 7.2 meters.
So what's that look like when you compare this to what you see here? Let me pop one more thing up here to show you before we go.
You can do this anytime. So check this out. Here you can show the map of Key West, or wherever you want to go in the world
figure out where exactly those trees are that you're thinking of. Let's say you were walking down the street and you saw a tree in this location.
How tall is that tree? So then you can see how well it matches up to what you thought.
You might have thought, oh, that tree looks like it's about, you know, five meters tall or six meters tall.
So each one of these dots represent
Each one of these arrows are pointing from where the tree height location is to where it is on the graph. So this is a fun way to do this.
That's about it. And I hope you learned a little bit and explore with the ICESat-2 data with Open Altimetry.
Remember, look up, you might see the ICESat-2 satellite overhead.
This is Brian Campbell, signing out. So you all have a good day. Bye.