A new joint assessment has warned that rising temperatures are increasingly destabilising global food production systems, placing the health and livelihoods of more than one billion people at risk.
The findings were published on Wednesday in a report titled Extreme Heat and Agriculture, produced by the Food and Agriculture Organization of the United Nations (FAO) and the World Meteorological Organization (WMO).
According to the report, the frequency, intensity, and duration of extreme heat events have increased significantly over the past 50 years, with widespread consequences for farming systems and natural ecosystems across the world.
It noted that livestock begin to suffer heat stress at temperatures above 25°C, while major crop yields decline once temperatures exceed 30°C. Marine life is also affected, as fish exposed to elevated water temperatures face risks such as cardiac failure. The report further revealed that in 2024, about 91 per cent of the world’s oceans experienced at least one marine heatwave.
Beyond food production, extreme heat is also emerging as a serious occupational hazard. In regions including South Asia, sub-Saharan Africa, and parts of Central and South America, conditions may become too hot for outdoor work for as many as 250 days annually, contributing to an estimated global loss of around 500 billion working hours each year.
The study described extreme heat as a “risk multiplier,” intensifying challenges such as droughts, wildfires, and the spread of pests and diseases.
It recommended a range of adaptation measures, including the development of heat-resistant crop varieties, changes in planting calendars and crop selection, and improved farm management practices to reduce exposure to high temperatures.
FAO Director-General Qu Dongyu stressed that extreme heat is placing growing pressure on crops, livestock, fisheries, and forests, while WMO Secretary-General Celeste Saulo noted that it acts as a compounding climate risk that worsens existing vulnerabilities in agricultural systems.
The report also emphasised that addressing the crisis will require not only technical innovation but also efforts to overcome socio-economic challenges in low- and middle-income countries