Rising CO2 Promoting Desert 'Greening'

July 08, 2013; 2:11 PM
Increased levels of carbon dioxide (CO2) over the past 30 years have caused an 11 percent increase in foliage over arid regions of North America, Australia, Africa and the Middle East, according to researchers from the Commonwealth Scientific and Industrial Research Organization (CSIRO) from Australia.
The image below is satellite data that shows the percent amount that foliage cover has changed around the world from 1982 to 2010. Note the biggest increases are in the arid regions of western North America, Africa and western Australia. Image courtesy of CSIRO.

This process, also known as CO2 fertilization, occurs where elevated CO2 enables a leaf during photosynthesis, the process by which green plants convert sunlight into sugar, to extract more carbon from the air or lose less water to the air, or both, according to the CSIRO press release.
The elevated CO2 causes individual leaves of a plant to use less water, thus plants in arid regions will respond by increasing their total number of leaves, according to the report.
Scientists have long known the effects of CO2 on foliage, but until now it has been difficult to demonstrate, according to CSIRO research scientist Dr. Randall Donohue.