WASHINGTON, USA, April 25, 2019 (NASA Earth Observatory): The world is literally a greener place than it was twenty years ago, and data from NASA satellites has revealed a counterintuitive source for much of this new foliage. A new study shows that China and India–the world’s most populous countries–are leading the increase in greening on land. The effect comes mostly from ambitious tree-planting programs in China and intensive agriculture in both countries. Research team found that global green leaf area has increased by 5 percent since the early 2000s, an area equivalent to all of the Amazon rainforests. At least 25 percent of that gain came in China. Overall, one-third of Earth’s vegetated lands are greening, while 5 percent are growing browner. The study was published on February 11, 2019, in the journal Nature Sustainability.
“This long-term data lets us dig deeper,” said Rama Nemani, a research scientist at NASA’s Ames Research Center and a co-author of the study. “When the greening of the Earth was first observed, we thought it was due to a warmer, wetter climate and fertilization from the added carbon dioxide in the atmosphere. Now with the MODIS data, we see that humans are also contributing.”Nemani sees a positive message in the new findings. “Once people realize there is a problem, they tend to fix it,” he said. “In the 1970s and 80s in India and China, the situation around vegetation loss was not good. In the 1990s, people realized it, and today things have improved. Humans are incredibly resilient. That’s what we see in the satellite data.”