Watching the planet breathe
When plants photosynthesize, they use energy from sunlight to turn carbon dioxide from the air into sugars used to live and grow. In doing so, they give off a fluorescent light — a glow that can’t be seen with the naked eye, but that can be seen with the right instruments. More photosynthesis translates into more fluorescence, meaning that the plants are very productive in taking up carbon dioxide. The amount of carbon dioxide taken up by plants is called “gross primary productivity,” and is the largest part of the global carbon cycle.