The space agency’s ICESat-2 satellite estimates the height of trees from space, and NASA has created a new tool for citizen scientists that can help check those measurements from the ground.
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.
When you first open it, an earnest tutorial walks you through how to calibrate the app and take the measurements that lets it triangulate tree heights.
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.
Since the official launch at the end of March, GLOBE Trees has received about 700 measurements from around 20 different countries, according to senior NASA Earth Science outreach specialist Brian Campbell, the Trees Science lead.