We wrote about this research earlier this week, but it’s worth drilling deeper into what makes these findings so consequential for the carbon removal industry.
The core finding from Johannes Bednar’s team at IIASA: reaching net zero doesn’t freeze climate damage in place. Sea levels keep rising. Permafrost keeps thawing. These slow-response systems operate on timescales measured in centuries, not decades — and they don’t stop just because we stopped adding CO₂.
The Slow-Motion Problem
Here’s what makes this research different from the usual “we need more CDR” argument. Most climate models focus on temperature as the key variable. Stabilize temperature, stabilize the planet. But Bednar’s analysis shows that’s wrong for two critical Earth systems.
Sea-level rise continues because heat already stored in the ocean keeps water expanding. Ice sheets respond to warming with multi-century lag times. Even if we hit 1.5°C and hold it perfectly, oceans keep rising for generations.
Permafrost thaw accelerates on its own timeline. Once soils warm past a threshold, microbes wake up and start converting ancient organic matter into CO₂ and methane. That adds roughly 5% to total carbon removal needs — not huge in percentage terms, but enormous in absolute tonnes.
The IPCC has warned that sea levels will keep rising beyond 2100 even in the best scenarios. Bednar’s contribution is quantifying what it would take to actually stop these processes: sustained net-negative emissions for centuries.
What “Centuries” Means for CDR
This isn’t academic hand-waving. It has direct implications for how we think about carbon removal infrastructure.
Current CDR commitments are framed in terms of reaching net zero by 2050. The implicit assumption is that we build CDR capacity, use it to close the gap, and then maintain some steady-state level. Bednar’s work suggests the actual need is different: we need to keep removing carbon at scale long after net zero, potentially for hundreds of years, to draw down the atmospheric CO₂ concentration enough to arrest these delayed impacts.
That changes the economics. CDR isn’t a bridge technology — it’s permanent infrastructure. The institutions we build to manage carbon removal need to last longer than most nations have existed.
The Governance Challenge
A second analysis from the same group tested what happens when policymakers treat these delayed impacts as risks to be avoided from the start. The result: net zero arrives about a decade sooner, and carbon pricing roughly doubles.
Acting cautiously changes the math before the damage is unavoidable. But it requires political systems capable of responding to risks that play out across generations — exactly the kind of long-term thinking that climate policy has consistently failed to deliver.
“Delayed impacts are not abstract future risks — they represent significant harm affecting hundreds of millions of people through sea-level rise and infrastructure damage,” Bednar said.
Why This Matters for CDR Investors
If carbon removal is needed for centuries, not decades, then the market for durable CDR is structurally larger than most projections assume. Long-duration storage — geological sequestration, mineralization, deep ocean — becomes even more valuable relative to shorter-lived approaches. And the case for building CDR infrastructure that can operate at industrial scale for the long term gets significantly stronger.
Sources: Earth.com, Phys.org, Bednar et al., Environmental Research Letters (DOI: 10.1088/1748-9326/ae34ca)