The greenhouse gas, CO2, is behind the greening up of some arid regions in the world, according to a recent study published in the journal Geophysical Research Letters.
Rising global temperatures, melting polar icecaps, possible flooding of coastal areas around the Earth, holes in the ozone layer, more acidic oceans, rising pollen counts, and increased rates of skin cancer are all some of the bad effects of greenhouse gas and global warming.
Still, the one upside of the rising levels of CO2 is that they appear to be greening up some of our planet’s arid regions.
Satellite data has shown that foliage around the globe has been increasing, according to scientists, since the 1980s. Carbon dioxide seems to be acting like a fertilizer, and to be the main factor behind this greening up. Scientists have just recently realized the cause was CO2 gas.
Atmospheric carbon dioxide is the heat-trapping greenhouse gas emitted by the burning of fossil fuels.
“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,” according to lead author Randall Donohue of the Commonwealth Scientific and Industrial Research Organization (CSIRO) in Canberra, Australia.
“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.”
Data from 1982 to 2010 was examined thoroughly by a team of researchers, who then predicted that there would be a 5 to 10 percent increase in foliage correlating with the 14 percent increase in carbon dioxide.
There was an 11 percent increase in greenery during that time period, the data indicated, providing “strong support for our hypothesis,” as the team put it.
The southwestern corner of North America, Australia’s outback, the Middle East, and parts of Africa were the arid regions mentioned in the study. Precipitation factors and other outside variables that could have led to the increased vegetation were also taken into account.
According to Donohue, “The effect of higher carbon dioxide levels on plant function is an important process that needs greater consideration. Even if nothing else in the climate changes as global CO2 levels rise, we will still see significant environmental changes because of the CO2 fertilization effect.”
How does the increased amount of carbon dioxide in the atmosphere effect plants? Donohue explains it by saying:
“If elevated CO2 causes the water use of individual leaves to drop, plants will respond by increasing their total numbers of leaves.”
The “fertilization effect” could also alter the types of vegetation in these arid regions.
According to Donohue: “Trees are re-invading grass lands, and this could quite possibly be related to the CO2 effect. Long lived woody plants are deep rooted and are likely to benefit more than grasses from an increase in CO2.”
His team is the first to show a CO2 link, Donohue stated.
Written by: Douglas Cobb