Climate Change: Soil Could Speed Up Global Warming Way More Than We Thought
Newsweek, Oct. 5, 2017
Carbon dioxide in the air is causing the planet to warm—but the higher temperatures may cause still more carbon dioxide to end up in the atmosphere. And a new study published today in the journal Science suggests the impact could be larger and more complicated than scientists had previously expected, not to mention difficult to counter.
“This self-reinforcing feedback is potentially a global phenomenon with soils, and once it starts it may be very difficult to turn off,” lead author Jerry Melillo, an ecologist at the the Marine Biological Laboratory, told Newsweek. “It’s that part of the problem that I think is sobering.”
Melillo has spent almost three decades heating small sections of a Massachusetts forest owned by Harvard University and measuring how much carbon is released. The new paper reports on 26 years’ worth of data.
“This is the classic case study of how warming affects soil and soil carbon. It really gives us some good insight into how the planet’s stocks of carbon will be changing as the climate gets warmer,” Steven Allison, an ecologist at the University of California, Irvine who is not affiliated with the study, told Newsweek.
Melillo and his colleagues look at three different types of forest plots. In one set, they installed heating cables in the soil and set them to heat it about 10 degrees warmer than the air around it. In another type of plot, they installed the heaters but never turned them on, just in case the physical disturbance affects plants. The third set of plots were left untouched.