 The United Nations Environment Programme issued a stark assessment Wednesday of the trajectory of global temperatures. The target cap adopted by the 2015 Paris Agreement — 1.5 degrees Celsius above pre-industrial levels — is guaranteed to be overshot, the report says. To completely avert disastrous conditions for human lives and livelihoods is no longer possible. Our best shot is to brace for a much hotter world, and then try hard to cool things off. And for that, the report concludes, “rapid upscaling of CDR is critical.” UN agencies and international scientific panels have endorsed carbon dioxide removal (that is, withdrawing CO2 from the air rather than preventing its release) before, but rarely framed it as such a foundational need. The field ranges from the ultra-low-tech — i.e., plant more trees — to all manner of cutting-edge carbon-sucking contraptions. Today about 2.2 billion metric tons of CO2 are withdrawn annually through these methods. Fixing the climate will require that figure to rise as much as ten-fold by 2100, the UN report finds. The report is clear that replacing fossil fuels in the energy system is still essential; every ton not emitted now is one less that has to be drawn out later. But renewable energy, while we could certainly always use more of it, is basically doing fine. Global investment has tipped down from a 2024 peak, but not plunged. Costs continue to fall rapidly. AI, EVs, and air conditioners are driving an historic surge in power demand where every electron is welcome. Even in the US, with vanishing tax credits and a hostile government, I rarely hear any serious investors describe clean energy (except offshore wind, for now) as uneconomic. CDR is a different story. The trouble is, it requires huge amounts of land, time, and/or cash. “Even if global fossil CO₂ emissions reached zero and deforestation were halted entirely, it would take about 100 years of sustained afforestation and forest management activities at the current scale to reduce global temperature by 0.1°C,” the UN report concludes. The sum of global governments’ CDR-related reforestation pledges amounts to two-thirds of the world’s arable land, which would make CDR an even bigger threat to food security than climate change. Most tech-based methods remain inaccessibly expensive, according to Oxford researchers. And unlike renewables, which are valuable for many more reasons than being CO2-free, CDR is mostly economically useless without government policies to incentivize it. And those clearly aren’t happening at scale: There’s a gap of up to $1.6 trillion in annual investment from 2030 to 2050 between what’s in the expected CDR pipeline and what’s needed, according to McKinsey. CDR isn’t readily recast as an “energy security” issue, which makes it hard for most global politicians to grapple with these days. But if the UN report is right, we’re rapidly approaching a world in which ignoring CDR will be far more costly than finding new ways to do it better. |
