Climate, Sustainability, and Food Systems

Climate change threatens global food security through multiple, compounding pathways: rising temperatures and shifting precipitation patterns reduce yields of major staple crops in many regions, while an increased frequency of extreme weather events — droughts, floods, and cyclones — disrupts harvests and supply chains. The IPCC's Sixth Assessment Report, published in 2022, projects further yield declines for key crops across tropical and subtropical regions absent significant adaptation, even as elevated atmospheric carbon dioxide can modestly boost the yield of some crops while simultaneously reducing their protein, iron, and zinc content, a phenomenon documented by researchers including Samuel Myers and colleagues, with potential to push hundreds of millions more people toward micronutrient deficiency by mid-century. The 2022-2023 Horn of Africa drought, the region's worst in roughly four decades, illustrates how climate stress compounds with conflict and economic shocks to drive acute food insecurity.