Thanks to increased levels of CO2 in the atmosphere, the world’s deserts are getting a little greener through a process called “CO2 fertilization.” Scientists from CSIRO have been taking satellite data of the globe’s arid regions for the past three decades, and they found that there has been an 11 percent increase in foliage from 1982 to 2010 across parts of Australia, North America, the Middle East and Africa.
CO2 fertilization occurs when higher levels of carbon dioxide enable plants use less water in their leaves during photosynthesis. Plants respond by creating more leaves and increasing overall cover in arid areas. CSIRO scientists working on collaboration with Australian National University were able to use mathematical models in conjunction with satellite data to observe the effect. They first calculate the average greenness of areas over a three-year period to account for changes in soil moisture, and then grouped the information with other regions according to their amount of rainfall. They then identified the total amount of foliage a group could create from precipitation and monitored the changes over thirty years.
“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,” says CSIRO researcher Dr Randall Donohue.
While some parts of the Earth are seeing increases in plant cover, others have shifted towards becoming dryer, leading to desertification. As the CO2 levels increase, the numbers and types of plant species are expected from their territories in order to survive.
Images via CSIRO and the US Fish and Wildlife Service.