Thread by @geoengineering1

🚨Climate pathways to 1.5°C increasingly depend on land-intensive carbon dioxide removal (#CDR) like forestation and BECCS.

But new research shows these climate solutions could place major pressure on #biodiversity if deployed without safeguards.

Details🧵1/11

2/ Using five integrated assessment models, the study examines where large-scale CDR is projected to occur & and how often it overlaps with biodiversity hotspots and climate refugia, the places most critical for species survival.

3/ The analysis focuses on a moderate but realistic deployment level of 6 GtCO₂ per year:
• 3 GtCO₂/yr from forestation
• 3 GtCO₂/yr from BECCS
Even at this level, land pressures are already significant.

4/ In scenarios aligned with 1.5°C, models allocate up to 13% of global areas of high biodiversity importance to land-intensive CDR such as forestation and bioenergy crops.

5/ Around 11% of remaining climate refugia - areas resilient to peak warming - overlap with forestation, while ~4% overlap with BECCS in 1.5°C pathways. These are ecosystems species depend on as the climate changes.

6/ Crucially, the risk isn’t CDR per se, but how and where it is deployed.

Avoided warming from forestation and BECCS could reduce warming-related climate refugia loss by up to ~25%, but this gain is offset when refugia are directly converted for CDR deployment.

7/ The burden is also uneven.

The models allocate up to 15% of biodiversity-relevant land in low and middle-income countries (despite their lower historical emissions, raising equity & governance concerns) to forest-based CDR, compared to just 7% in wealthy countries.

8/ What if biodiversity were fully protected?

The authors test this, and find that over 50% (median) of land allocated for forestation and BECCS would be unavailable by 2050 if current biodiversity hotspots were excluded.

9/ Crucially, these land constraints emerge as early as 2030, meaning conflicts between climate mitigation and biodiversity protection are not a future risk, they’re imminent.

10/ However, the paper also identifies pathways for synergy:

Prioritising degraded lands, avoiding intact ecosystems, diversifying CDR portfolios, and embedding biodiversity constraints directly into climate models.

🗓️For more details, read the study entitled "Biodiversity implications of land-intensive carbon dioxide removal" here:


🧵11/11 #CDR #Biodiversity #BECCS #Reforestationnature.com/articles/s4155…

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