How will rising temperatures impact global food security?

Rising temperatures undermine global food security by reducing production potential, destabilizing supply chains, and worsening the economic and nutritional access that determines whether people can eat. International assessments and peer-reviewed research emphasize that heat affects both the quantity and reliability of food supplies while interacting with water scarcity, pests, and extreme weather to magnify harm. The Food and Agriculture Organization of the United Nations highlights that climate variability and warming are already altering crop and livestock productivity worldwide. Research by Marshall Burke at Stanford University and Solomon Hsiang at University of California, Berkeley demonstrates that higher temperatures systematically reduce yields and increase year-to-year variability, especially in tropical regions where crops operate closer to physiological limits.

Mechanisms: how heat affects crops, livestock, and fisheries
Higher air and soil temperatures reduce photosynthetic efficiency for many staple crops during critical development stages, impair pollination, and increase plant respiration, lowering net growth. Heat also accelerates evapotranspiration, deepening drought stress where water supplies are limited. Livestock suffer from heat stress that lowers fertility, milk and meat output, and increases susceptibility to disease. Marine systems respond to warming through species redistribution, reduced oxygen levels, and altered primary productivity, affecting small-scale fisheries that supply protein to coastal communities. Christopher Field at Stanford University and contributors to the Intergovernmental Panel on Climate Change describe these pathways as interconnected risks that compound when heat coincides with floods or pests.

Who is most affected and why
Impacts are uneven. Smallholder farmers in Sub-Saharan Africa, South and Southeast Asia, and parts of Latin America face outsized risks because low incomes limit investment in irrigation, improved seed, and storage. Indigenous and culturally specific food systems that rely on particular species or seasonal cycles are vulnerable to subtle shifts in timing and abundance. Urban poor populations are sensitive to price spikes when staple yields fall; the Food and Agriculture Organization of the United Nations notes that food price volatility has immediate nutrition consequences. Research by Solomon Hsiang indicates that climate-driven agricultural shocks can increase migration and heighten social tensions in regions with weak safety nets, turning localized crop losses into broader humanitarian and political crises.

Consequences and adaptation choices
The foreseeable consequences include higher prevalence of undernutrition where adaptive capacity is low, greater volatility in global markets, and the potential for ecological consequences such as expanded land conversion when farmers try to compensate for lower per-hectare yields. Adaptation options already being tested include heat-tolerant crop varieties, improved water management, climate-smart livestock practices, and social protection programs that stabilize incomes during bad seasons. Rosamond Naylor at Stanford University and colleagues emphasize that adaptation must be regionally tailored, combining technological, institutional, and cultural measures to protect dietary diversity and local food traditions. Without rapid mitigation of greenhouse gas emissions and targeted investments in adaptation, rising temperatures will increasingly strain the ability of food systems to deliver stable, nutritious diets for billions.