It’s Time to Delete Carbon From the Atmosphere. But How?

This week and next, government representatives are gathering in Glasgow for the United Nations Climate Change Conference, or COP26 , the latest of an increasingly frantic string of meetings as humanity runs out of time to drastically reduce our greenhouse gas emissions. Everyone agrees that carbon is bad. And everyone agrees it’s hard to get rid of; carbon dioxide lasts up to a thousand years in the atmosphere. The world even has a common goal: keeping global temperatures from reaching 1.5 degrees Celsius above pre-industrial levels , the boundary set by the Paris Climate Agreement.But nations don’t agree on how we’ll get there: Staving off the worst of climate change will require cutting carbon emissions and developing ways to pull them out of the atmosphere. Here are some of the options delegates will likely be discussing as COP26 continues.

The Problem With Net Zero

You’ve probably heard of a sticky little concept known as net-zero emissions: If you put any carbon into the atmosphere, you have to take the same amount out. On Monday at COP26, India’s Prime Minister, Narendra Modi, announced that his country would reach that goal by the year 2070. Earlier this year, President Joe Biden said the United States would do the same by 2050, a goal the UK has also pledged to achieve.It’s a popular idea, although it’s based on achieving the bare minimum. “I think the main reason we're going probably see a lot of discussion about it at COP26, and certainly going forward, is that the world continues to pay lip service to the idea of limiting warming to one and a half degrees,” says Zeke Hausfather, a climate scientist and the director of climate and energy at the advocacy group the Breakthrough Institute.

The problem with net zero is that it doesn’t mean that these countries will stop spewing greenhouse gases by those target dates. It just means that by that point, they won’t be adding any to the atmosphere in aggregate. Net-zero can be a cop-out, because it allows nations to keep polluting so long as they’re also capturing that pollution. It’s a bit like trying to drain a bathtub with the tap still running full blast.

It might even encourage nations to keep spewing greenhouse gases, so long as they’re also sequestering them. Or a country might make a big deal about offshoring its carbon-intensive industries like steel production, disavow all those emissions, and then just import those materials anyway. Corporations, too, aren’t incentivized to actually reduce their emissions if they can just buy carbon credits . “It is absolutely a very reasonable concern and something we all have to guard against,” says Angela Anderson, director of industrial innovation and carbon removal at the nonprofit World Resources Institute, “the temptation and certainly the desire by some interests in the fossil fuel industry to not have to reduce emissions to preserve their existing business plans.”