NASA Scientists Employ Satellites to Create Global Plant Productivity Maps (Video)

What do plants and space have in common? NASA scientists have developed a new way to use satellites to measure what's occurring inside plants at a cellular level. The technique could help researchers measure overall plant health from space, which will give them a broad view of how entire ecosystems are doing as a whole.

Plants use photosynthesis in order to grow, converting sunlight into the energy that they need to survive. During this process, though, plants emit what is called fluorescence. This light is invisible to the naked eye but can be detected by satellites in orbit. While abundant fluorescence indicates a well-functioning plant, low or no fluorescence can mean that a plant is stressed or slowly dying. Needless to say, the ability to measure this fluorescence can give scientists a better look at how plants are coping across the entire planet.

In order to measure and see this fluorescence, the researchers created maps using the data from satellites. Yet creating these maps wasn't easy. The researchers had to examine the signals that were collected by the satellites, teasing out which belonged to fluorescence, Earth's surface or the atmosphere. In the end, though, they managed to create global maps.

The newly created maps boast a 16-fold increase in spatial resolution and a three-fold increase in temporal resolution over the first concept maps released in 2011. They show immediate and direct information about plant productivity, revealing how climate it affecting plant health.

"For the first time, we are able to globally map changes to fluorescence over the course of a single month," said Joanna Joiner of NASA's Goddard Space Flight Center in a news release. "This lets us use fluorescence to observe, for example, variation in the length of the growing season."

Despite its complexities, the new method does allow for more frequent measurements that are able to produce higher resolution maps. This could be a boon to scientists that are studying how climate affects plants on a global scale. In addition, the new maps could also help farmers and even show researchers some unprecedented details about Earth's surface.

"The more precise and more frequent sampling is valuable, allowing us to zoom in on the regions with the highest fluorescence signals," said Joiner in a news release. "Our data indicate that agricultural areas in the U.S. Midwest are some of the most productive lands on Earth. We can also now correlate our satellite fluorescence measurements with tower-based observations of carbon dioxide taken up by plants."

Want to see the maps and learn more about them? Check out the video below, courtesy of NASA and YouTube.