This one is for you if you’re in the habit of taking a lot of photos of nature. NASA would like you to take a picture of a tree. The space agency’s ICESat-2 satellite estimates the height of trees from space.
To make ensure that the measurement is okay, NASA has created a new tool for citizen scientists that can help check those measurements from the ground. All you need is a smartphone, the app and a tree.
The ICESat-2 satellite was launched in September 2018. It carries an instrument called ATLAS , the Advanced Topographic Laser Altimeter System. It has three major tasks: Send pulses of laser light to the ground, collect the returning photons in a telescope, and record the photon travel time. It carries two lasers, one primary and one backup.
The laser light is at 532 nanometers, a bright green on the visible spectrum. It shoots 10,000 pulses at the Earth’s surface per second it orbits the planet.
launching of ICESat-2 satellite; Image Source: icesat-2.gsfc.nasa.gov
The satellite is fast-firing as compared to the laser on the first ICESat, which sent 40 pulses per second. “It’s basically a laser in space,” says Tom Neumann, the project scientist for ICESat-2 at NASA Goddard Space Flight Center.
By measuring the satellite’s position, the angle, and how long it takes for those laser beams to bounce back from the surface, scientists can measure the elevation of sea ice, land ice, the ocean, inland water, and trees. But one data point isn’t sufficient to determine elevation. So the computer programs look for the stronger signals.
NASA Wants You to point Smartphone At Trees And Help Save Environment; Image Source: Elsevier
Knowing how tall trees are can help researchers estimate the health of the world’s forests. Also, modern civilization has a giant Greenhouse gas problem. Like the windows in a greenhouse, these gases trap energy from the sun as heat. Earth would be quite cold and unfriendly in manner without their role in this greenhouse effect.
Global temperatures would average around -18° Celsius, according to the National Oceanic and Atmospheric Administration (NOAA). Instead, the surface of our planet averages around 15 °C, making it a comfy place for life. But human activities have been releasing extra greenhouse gases into the air which is slowly rising the average temperatures across the globe.
Graph showing the rise of Carbon Dioxide; Image Source: climate.nasa.gov
Among all greenhouse gases C02 is having the spotlight. Carbon dioxide levels are the highest they’ve been in millions of years. And, critically, the rate of CO2 increase in the last 50 years isn’t just unpredictable in human history, it’s unprecedented in the geologic record.
This increasing CO2 is trapping the heat more than ever making the environment warmer more than ever. Trees help us by soaking the C02 gas and making environment healthy. Knowing how tall trees are can help researchers estimate the amount of carbon dioxide they can soak up.
Now the most challenging task is to determine how good those measurements from space actually are. That’s where the citizen scientist comes in to help to verify them. “You can’t really ask a bunch of school kids in Pennsylvania to go to Antarctica to measure the ice sheet height for you for a calibration,” Neumann says.
But it is possible to ask them to take their smartphones outside, and take a picture of a tree, which is exactly what NASA is doing with its GLOBE Observer app. “You’ve got all sorts of great terrain and features right in your backyard that you could go out and do these measurements that would be useful for us,” Neumann says.
The Globe Observer app; Image Source: www.visiontimes.compp
To help NASA, all you need to do is download the the NASA GLOBE Observer app. It is a user friendly app. You will get many different tools like recording cloud observations, mosquito habitats, and nearby landscape around you. There’s also a new tool for measuring trees, called GLOBE Trees.
Built-in mathematical program that calculates the tree height using observations; Image Source: twitter.com
You will get an easy tutorial as soon as you open the app for the first time which will teach you how to calibrate the app and take the measurements that let it triangulate tree heights. The tutorial includes helpful tips for things like “Selecting a tree” because bent and broken ones don’t get measured.
First you will need to select a non-broken tree and stand about 25 to 75 feet away. Then you hold the phone right in front of your face and angle it to measure the base and then the tree’s top. Then you take a picture, count your steps to the tree, log your position at its base, and the app spits out the tree’s height.
The research team say they’ve received about 700 measurements from 20 different countries since the app launched, but they’d love to get even more. Everyday we all keep clicking for Facebook, Instagram and more. Let us do this now for scientific purpose.
Featured Image Source: twitter.com