Gongloff: Carbon-capture plans require huge land grab

Because it’s apparently too hard to cut the carbon emissions heating up the planet, many countries plan to sweep much of their pollution under the rug instead. This might be fine, except the rug will have to be the size of the entire U.S., according to a new study.

The net-zero promises made by 140 countries will require turning about 3.8 million square miles into a giant carbon-dioxide sponge, according to a new study in the journal Nature Communications. That’s almost exactly the size of all the land and water within U.S. borders.

And 44% of that land would have to be repurposed, the study estimates. That would mainly mean planting trees where crops or shops or other non-tree things used to be. Some of it would be dedicated to bioenergy crops, or plants burned for fuel. The other 56% of the land would be restored forests, mangrove swamps and other tree-friendly terrain.

Obviously, trees are great. They cool people down, provide housing for creatures and look beautiful. But they are suboptimal as carbon-removal machines. It takes years for them to reach their full carbon-drinking potential. And because they’re destined to either catch fire, fall over or die within a century or so, their carbon removal isn’t permanent.

Simply paying people to plant trees has long been a predominant feature of the carbon-offsets market, which is one reason offsets are widely considered to be so sketchy. Entire countries relying on planting trees to absolve their own emissions is arguably worse, given the scale of the pollution involved. That’s even more alarming when you consider the four countries with the biggest carbon-sponge plans to balance their net-zero books are all huge fossil-fuel producers: Russia, Saudi Arabia, the U.S. and Canada, respectively.

The even bigger practical problem with these schemes is the ludicrous amount of land involved. Earth simply isn’t going to cough up another half a continent to serve as a global arboretum. That means vast amounts of land would have to be quickly converted to meet net-zero goals.

To get a taste of the political and social upheaval that might ensue, you need only look to the recent past. Soaring food prices in 2007 and 2008 led to a global land rush, with private investors and sovereign wealth funds snatching up cropland across the Global South. Between 2007 and 2014, 27,000 square miles a year were bought from local owners and transformed, the study estimates, mostly to industrial farming to grow food that was shipped overseas. Local farmers and natural habitats suffered, while food insecurity, inequality and political instability rose. The land grab necessary to meet net-zero goals would be twice as large and go on for decades.

And yet some of the same countries ravaged by the recent land rush plan to dedicate huge swaths of their territory to carbon capture, the study points out. Several countries in sub-Saharan Africa plan to use 20% of their land for such purposes, risking more misery and upheaval for their people.

Mark Gongloff is a Bloomberg Opinion editor and columnist covering climate change. /Tribune News Service