Balancing climate and biodiversity: Assessing the socioeconomic impacts of the 30-by-30 target with climate warming constraints

Limiting global warming to 1.5°C will require significant land-use change. Various post-Paris Agreement strategies are rooted in land-based CO2 removal. However, these strategies introduce potential mismatches with biodiversity conservation policies. Given this, our study evaluates the compatibility between the UN Kunming-Montreal Global Biodiversity Framework’s “30-by-30” target—protecting 30% of land and oceans by 2030—and two climate change scenarios: “Current Trends” (CT), which extrapolates present climate policies through the century, and “Accelerated Actions” (AA) which seeks to stabilize average temperatures at 1.5°C. We apply a multi-sector computable general equilibrium model (MIT Economic Projection and Policy Analysis), where the 30-by-30 target is implemented by protecting biodiversity-rich natural forest and grasslands while prioritizing subsidy-based transition to these land types. Under CT and AA, India and the Middle East will experience the largest GDP losses, up to tens of billions of dollars, as a result of combining the 30-by-30 target. Meanwhile, Brazil and Australia and New Zealand will experience billion-dollar magnitude growth. Outputs further magnify the distributional effects of the 30-by-30 target, where the Middle East and India will experience substantial food price increases ranging from 5% to 600% in certain agricultural products. These results highlight disparities for regions with deficient natural forest and grassland cover, but also the potential comparative advantage for strong agri-livestock regions that would benefit from increased food exports. Overall, our outputs provide a socioeconomic insight into the effects of a dual biodiversity-climate intervention that can guide policymakers to develop complementary strategies that regulate policy ramifications, including food-price impacts and agriculture-induced deforestation.