Rising atmospheric carbon dioxide levels are bolstering plant life in arid regions throughout the world, environmental scientists report in a newly published peer-reviewed study analyzing satellite data. The findings contradict assertions by global warming alarmists that deserts are expanding as the planet modestly warms.
A team of scientists led by environmental physicist Randall Donohue, a research scientist at the Commonwealth Scientific and Industrial Research Organization in Australia, compared satellite images and data from 1982 through 2010. The scientists documented a carbon dioxide “fertilization effect” that has caused a gradual greening of the Earth’s arid regions since 1982.
The satellite data showed a remarkable 11 percent increase in in foliage due to rising carbon dioxide concentrations.
“Lots of papers have shown an average increase in vegetation across the globe, and there is a lot of speculation about what’s causing that,” said Donohue in a press release accompanying the study. “Up until this point, they’ve linked the greening to fairly obvious climatic variables, such as a rise in temperature where it is normally cold or a rise in rainfall where it is normally dry. Lots of those papers speculated about the CO2 effect, but it has been very difficult to prove.”
“On the face of it, elevated CO2 boosting the foliage in dry country is good news and could assist forestry and agriculture in such areas; however there will be secondary effects that are likely to influence water availability, the carbon cycle, fire regimes and biodiversity, for example,” Donohoe added.
Plant life in the United States has especially benefited from rising atmospheric carbon dioxide levels and gradually warming temperatures. Satellite data show foliage has increased in the vast majority of the United States since 1982, with the western United States benefiting the most. Many regions of the western United States experienced a greater than 30 percent increase in foliage since 1982.
James M. Taylor ([email protected]) is managing editor of Environment & Climate News.
“Elevated carbon dioxide making arid regions greener,” AGU Press Release, http://www.agu.org/news/press/pr_archives/2013/2013-24.shtml