With @docaharper.bsky.social from @universityofga.bsky.social @exeter.ac.uk, Gabriel Abrahão, from @pik-potsdam.bsky.social and @rosieafisher.bsky.social, from @cicero.oslo.no

#CarbonBudget #Mitigation

...These “known unknowns” compound the risks associated with overreliance on land-based mitigation.

⚠️This leads to a broader warning: betting on a strong land sink is inherently risky — even if current stocks were to remain stable over time.

Why it matters 👉 bit.ly/4qMYPEy

While uncertainties in how the land responds to climate change — including feedbacks involving drought, temperature, pests,or tipping points — may be comparatively smaller than those of the baseline C stocks, they remain significant & poorly understood....

That uncertainty alone can swing Paris-compatible carbon prices from ~$450 to >$600/tCO₂ in our scenarios — without changing climate sensitivity or tech costs, for example.

Eager for more details?
👀 Check our full Research Highlight here:bit.ly/4qMYPEy

With @docaharper.bsky.social from @universityofga.bsky.social @exeter.ac.uk, Gabriel Abrahão, from @pik-potsdam.bsky.social and @rosieafisher.bsky.social, from @cicero.oslo.no

Our analysis suggests that uncertainties in current carbon stocks are even larger than those related to how these stocks may respond to future climate change... (6/7)

They also support a broader conclusion👇

Climate mitigation assess. often focus on uncertainties in the climate system (e.g.climate sensitivity)➡️uncertainties in the land C cycle, esp. in current C stock densities, remain underexplored.

👉These uncertainties play a decisive role in shaping costs/feasibility of land-based mitigation.(5/7)

...while IAMs need to know how much C is stored in diff. land types (i.e. per-area C values for diff. land-use types) to estimate land-use change emissions & project mitigation potential.
➡️IAMs depend heavily on C density assumptions, yet these are often highly uncertain & poorly constrained (4/7)

This exposed a critical communication gap: ESMs & economic models speak different "carbon languages"

The problem is simple but profound:
👉ESMs report how C stocks change over time (i.e.C fluxes) & report the values aggregated over a grid cell (not the land-use type values needed by IAMs)...(3/7)

We carried out, for the 1st time, a systematic comparison of how different ESMs simulate land-based CDR measures across a range of scenarios➡️When these results were shared with the IAMs, it became evident that diff. ESMs were providing land-related data with highly diverse formats/key variables(2/7)

Land-use strategies must account not only for C storage potential, but also for wider impacts on food systems, water resources & ecosystems:🔎bit.ly/4qMYPEy

@docaharper.bsky.social @universityofga.bsky.social @exeter.ac.uk G.A. @pik-potsdam.bsky.social @rosieafisher.bsky.social @cicero.oslo.no

🌡️🌿The models also showed that the land's ability to store carbon may weaken over time, especially in warmer and drier conditions.

➡️This could make it harder to meet climate goals if too much reliance is placed on land-based removals.

#ESM2025research
(3/4)

💦 Irrigation can lower land surface temperatures and increase humidity, but may reduce runoff and alter regional water availability.

🚜🌿Large-scale bioenergy crops may help remove CO₂, but can also compete with food production and strain water resources.

(2/4)

...Jens Heinke, Michael Crawford, Elmar Kriegler @pik-potsdam.bsky.social, Sirisha Kalidindi and @joerirogelj.bsky.social @granthamicl.bsky.social, and Gang Tang @unimelb.bsky.social

.

... and thanks to all the work of the researchers in ESM2025 contributing to this exciting research topic: Emma Littleton
@exeter.ac.uk, Kjetil Schanke Aas
@cicero.oslo.no, @aargles.bsky.social
and Eddy Robertson @metoffice.gov.uk...

... , Jens Heinke, Michael Crawford, Elmar Kriegler @pik-potsdam.bsky.social, Sirisha Kalidindi and @joerirogelj.bsky.social @granthamicl.bsky.social, and Gang Tang @unimelb.bsky.social.

... and thanks to all the work of the researchers in ESM2025 contributing to this exciting research topic: Emma Littleton @exeter.ac.uk, Kjetil Schanke Aas @cicero.oslo.no, @aargles.bsky.social and Eddy Robertson @metoffice.gov.uk...

@pfriedling.bsky.social might interest your community as well!

With three of our Core Theme 3 researchers: @docaharper.bsky.social from @universityofga.bsky.social @exeter.ac.uk, Gabriel Abrahão, from @pik-potsdam.bsky.social and @rosieafisher.bsky.social, from @cicero.oslo.no

www.esm2025.eu/about-the-p...