Climate-driven global cropland changes and consequent feedbacks

Abstract

<p>The interdependence of climate change and agricultural land use remains a critical, yet unquantified, area of concern for future food production. Here we determine climate-driven cropland change based on an empirical model of cropland response to changes in agricultural productivity. By estimating counterfactual total factor productivity in a scenario without climate change, we find that 88 million hectares (90% confidence interval (CI) 5–179 Mha), or 6.3% (90% CI 3.6–12.8%) of the cropland currently used in 110 countries, can be attributed to climate change via reduced agricultural productivity growth over 1992–2020. This area exceeds the observed 3.9% net cropland expansion in the studied countries, indicating that total cropland area would have decreased in the absence of climate effects. The release of about 21.8 GtCO2 (lower/upper bound: 4.4–41.4 GtCO2) could have been prevented without climate-driven cropland change, accounting for about 18.9% (3.8–35.9%) of land-use change emissions in these countries. Climate-driven cropland change also triggered noticeably warmer and drier local climate feedback in some regions, with potential repercussions for food security. The substantial emissions will probably impose further long-term negative impacts on agricultural efficiency.</p>