NASA satellite data has shown that anywhere from 10 to 40 percent of improvements in key U. S. crop yields since 1940 could potentially be attributed to increased atmospheric carbon dioxide due to human activity, according to a new paper from Columbia University’s Charles A. Taylor and Wolfram Schlenker.
The authors noted that their findings are “on the very high end of the range found in the literature.”
“Taylor and Schlenker’s numbers are 10–100 times as large as previous estimates,” Richard S.J. Tol, a professor in the Department of Economics at the University of Sussex, told The Epoch Times via email. //
Their models were based on data from 2015 through 2020 collected by NASA’s Orbiting Carbon Observatory- 2 (OCO-2) satellite, which they replicated with NOAA’s CarbonTracker system. They also used county-level data on corn, soybeans, and winter wheat yields from the U.S. Department of Agriculture’s (USDA) National Agricultural Statistics Service. Taylor and Schlenker found that an increase of 1 part per million of carbon dioxide raised corn yields by 0.5 percent, soybean yields by 0.6 percent, and wheat yields by 0.8 percent. //
They also noted that the potentially dramatic fertilizing effect of atmospheric carbon dioxide might not be so unexpected, given how it’s used in actual agricultural greenhouses.
“The gas has long been pumped into greenhouses to spur photosynthesis and increase the yield of horticultural crops. Optimal CO2 concentrations of 900 [parts per million] have been suggested, which is over twice current ambient levels,” the authors wrote.
Taylor and Schlenker’s approach contrasts with field- and laboratorybased studies on carbon dioxide enrichment. The authors argued that such experiments “are limited in the extent to which they reflect real-world growing conditions in commercial farms at a large geographic scale.”
