The heterogeneous impacts of climate change on food security under SSP-RCPs scenarios: Evidence from Brazil, China, India, Russia, and the United States

Climate change profoundly affects food security through complex pathways. Prior studies focus on climate effects on crop growth but often neglect economic factors ’ mediating role, adding uncertainty in global food security assessments. We apply a climate - economy model (C-D-C model) to Brazil, China, India, Russia, and the US to quantify combined climate and economic impacts on food production and project future climate and cropland under SSP-RCP s scenarios , as well as their impacts on food production. Cropland generally expands, though variation depends more on socioeconomic pathways, with regionally uneven gains and losses. The impacts of climate change are heterogeneous across various regions. Tropical and developing nations (e.g., Brazil and India) exhibit greater climate sensitivity compared to advanced economies (e.g., China and the United States). An increase in mean temperatures substantially decreases Indian output (−1.751***) while benefiting certain Brazilian regions (2.348***). Extreme low temperatures negatively affect Chinese food production (−0.313**). The number of frost days in the United States poses a threat to production (−0.241**). Under future SSP-RCPs scenarios, Brazil is projected to gain, and the suitability of cropland in high-latitude countries (e.g., Russia) is expected to improve. Conversely, India's marginal benefits from expanding cropland remain negative, whereas the adverse effects of some climate factors in China and the United States gradually diminish. Under SSP5-RCP8.5, the impact of frost in the United States is anticipated to become positive. These findings underscore the importance of tailored, country-specific policies to enhance global food security. • The "Economic-Climate Model" was developed to comprehensively analyze the key drivers of food production in major food-producing countries. • The impacts of climate change and changes in cropland area on food production under future SSP-RCPs scenarios were projected. • Tropical and developing countries are disproportionately vulnerable to the adverse impacts of climate change.