<p>Global cropland use transformations are exacerbating disparities in environmental burdens between nations. Here, using a multiscalar nested driver framework to classify 174 countries (1992–2021) on the basis of their relative changes in harvest and cropland area, we show that 88% of global harvest area expansion occurred in countries of the global south, driving 82% of growth in cropland GHG emissions. Countries with low-efficiency expansion had the highest GHG intensities (1.7 kgCO₂e Mcal⁻¹), driven by land-use change for oil-crop cultivation. By contrast, countries with high-efficiency contraction achieved the lowest GHG intensities (0.4 kgCO₂e Mcal⁻¹) while reducing harvest area by 12%, yet this efficiency gain was accompanied by a 4.2-fold rise in crop imports from countries with high GHG intensities but low-efficiency expansion since 1992. Consequently, asymmetric intensification of cropland use deepens global disparities in environmental and ecological burdens. This framework captures drivers of asymmetric intensification and highlights the need for global accountability to prevent outsourcing ecological costs.</p>