26/04/2016 1:56 PM AEST | Updated 15/07/2016 12:52 PM AEST

How Carbon Dioxide Is Boosting The World's Plant Growth

Christopher Kimmel via Getty Images
The tip of a new Deer Fern (Blechnum spicant) leaf is illuminated by the morning sun.

Earth is dealing with increased gas emissions by sprouting millions of extra green leaves equivalent in area to the size of Australia.

What's more, this "significant greening" of Earth has happened in 33 years.

An international team of 32 authors from 24 institutions collaborated on the research, published in the journal Nature Climate Change using data from satellite sensors and computer models.

They found between one quarter to half of Earth's vegetated lands has become significantly greener, caused by extra leaves on plants and trees.


How does Carbon Dioxide encourage plant growth?

Green leaves produce sugars by using energy in sunlight and carbon dioxide drawn in from the air, along with water and nutrients pumped in from the ground.


More sugars are produced when there is more CO2 in the air, and this is called CO2 fertilisation.

This feedback loop between CO2 and increasing plant growth has long been touted by climate change deniers as proof that a cutback of emissions would have a negative effect on the environment but coauthor Philippe Ciais said there were errors in this view.

“The fallacy of the contrarian argument is two-­fold. First, the many negative aspects of climate change, namely global warming, rising sea levels, melting glaciers and sea ice, more severe tropical storms, etc. are not acknowledged," Ciais, who is Associate Director of the Laboratory of Climate and Environmental Sciences, Gif-­suv-Yvette, France, said in a statement.

"Second, studies have shown that plants acclimatize, or adjust, to rising CO2 concentration and the fertilisation effect diminishes over time.”

Here in Australia, this greening effect has the potential to change river systems. ARC Centre of Excellence for Climate System Science research associate Anna Ukkola said there were serious implications for our water resources.

Australia's waterways are sensitive to changes.

"Denser, greener vegetation can consume more water, in turn reducing the amount of rainwater that would otherwise run off into rivers," Ukkola said.

"Greening vegetation has been shown to significantly reduce river flows in drier parts of Australia in the recent decades, and can thus have important implications for regions with already limited water resources."