The latest report from United Nations climate scientists does the arithmetic of a net-zero world.
The Intergovernmental Panel on Climate Change (IPCC) concludes—more categorically than ever—that we’ve already overshot key greenhouse gas emissions thresholds, and all climate mitigation scenarios require astonishing actions.
In particular, the report cements carbon dioxide removal technology as a critical, required component of emissions abatement and climate mitigation. This type of tech pulls carbon out of the air and oceans.
The report solidifies another important concept: while useful, nature-based carbon removals alone—like creating new forests—won’t be enough. The limits to land and water, and the sheer tonnage required of removals, makes nature-based solutions insufficient.
To quote Roy Scheider in “Jaws”: We’re gonna need a bigger boat.
The authors state categorically that carbon removal technologies are required—”need to have,” not “want to have”—to stabilize climate change at relatively safe levels. Depending on how we invest and the risk we’ll accept for “safe” stabilization, we will need between 75 billion and 200 billion tons of cumulative carbon removal by 2060—estimates similar to those of the Energy Transition Commission and the International Energy Agency.
For perspective, 75 billion tons is 150 times the weight of all humans on Earth (and perhaps as much as 400 times is needed). Plus running a global industry the size of the global oil and gas industry, in reverse, for another century.
That’s what we get for waiting a century to clean our room—the planet where we live.
For well over a decade, scientists and decision makers have known the risk of overshoot—exceeding the carbon budget for a sustainable world—was high, growing and frightening.
What’s worse, global greenhouse gas emissions rose again last year to a record high level, including increased use of coal and continued, widespread deforestation.
Since the IPCC is the platform from which the world’s climate and energy experts speak with clarity and consensus, it reflects a consolidation of that consensus position: the necessity of CO2 removal as a plank of climate change mitigation.
For many years, this discussion was not particularly welcome in polite climate circles. The main concern was moral hazard, the idea that creating an option to remove emissions would limit ambition to abate them.
I’ve been working in this space of climate mitigation and carbon management for 20 years. It’s invigorating to see the IPCC underscore the importance of carbon removal technologies and a real triumph of arithmetic.
The good news to accompany the IPCC’s warnings is that we have already demonstrated these technologies.
We can (and do) use bioenergy to remove carbon from the air and oceans and combine it with carbon capture to keep it under geological lockdown. We can (and do) suck small volumes of CO2 from ambient air using direct-air capture machines. We can (and do) convert CO2 to stone right at the earth’s surface using mine tailings, industrial wastes and specialty minerals.
Major companies, from Microsoft and Shopify to GlaxoSmithKline and Airbus, have added these technology options to their CO2 removal purchases explicitly to scale up deployment of technology-enabled CO2 removal. And many have done so in partnership with Carbon Direct.
The IPCC team makes the case that these new technology pathways can provide the most abatement and scale most quickly and profoundly. By underscoring the importance of carbon removal technologies to reaching a net-zero emissions future, the IPCC is making the case for what we need now: investment, innovation and commitment.
Innovation and investment go hand in hand. Investment in building facilities stimulates innovation, which lowers cost and risk, which stimulates new investment. Myriad cleantech solutions, including solar, wind, light bulbs, batteries and electric vehicles, have followed this recipe. We must follow it again with carbon removal.
The IPCC’s consensus on carbon removal is a welcome development. I hope it prods governments and companies to accelerate their commitments supporting and deploying this essential technology.