Rainforests, whether in the Amazon, Southeast Asia or Central America, are hotspots of organic productivity, teeming with life. Fueled by abundant rain and a reliable stream of nutrients, the Amazon blooms year-round. For a brief period each summer, however, the ingenuity of humankind trumps even the mighty rainforests at biological production. At the peak of the growing season, says NASA, the Midwest U.S. corn belt is the most productive place on Earth—there's more photosynthesis going on here than even in the Amazon.
When plant cells photosynthesize, part of the energy they produce is emitted as fluorescent light. By measuring the strength of this fluorescence from space, scientists can get a measure of plant productivity—as they did in a recent study. NASA has a video explaining in more detail the process of fluorescence, and how the image above was put together:
The difference between the corn belt productivity's and the Amazon's is the incredible amount of inputs that go into creating growth in the U.S. We have to draw on vast resources to power unnatural temporary growth in a concentrated area. But, for a short period of time, it means we can produce far beyond what natural ecosystems like the Amazon can muster.
H/T Climate Central