PHNOM PENH: The FAO has warned that extreme heat is rapidly reshaping global food security, with urgent action needed to shift from reactive crisis management to proactive heat preparedness. With rising temperatures expected in the coming years — and another El Nino likely to strain already vulnerable systems — the need to act has become increasingly pressing.
An April 22 joint report by the FAO of the UN and the World Meteorological Organization highlighted how escalating heat is emerging as a major threat to food production, rural livelihoods and agricultural workers worldwide.
The report explained that all crops, livestock and fish species have thermal limits — thresholds beyond which heat begins to cause damage rather than support growth — and warns that these limits are being reached faster than many anticipate.
For many essential crops, critical stress begins between 25°C and 35°C, particularly during key growth stages such as flowering and reproduction. However, as climate change pushes temperatures into the mid-40s°C in major agricultural regions, these thresholds are increasingly being exceeded.
The consequences include declining crop yields, weakened livestock, stressed fisheries, heightened wildfire risks and unsafe working conditions for farmers.
Kaveh Zahedi, assistant director-general of FAO’s Office of Climate Change, Biodiversity and Environment, stressed the urgency of the situation, noting that extreme heat is already reducing agricultural output and exposing workers to dangerous conditions.
The report found that cattle mortality has reached up to 24 per cent during severe heatwaves, while marine heatwaves have caused an estimated $6.6 billion in fisheries losses. Additionally, for every 1°C increase in temperature, maize and wheat yields are projected to fall by 4 to 10 per cent.
As extreme heat intensifies, the report emphasised the importance of early warning systems and practical adaptation strategies to help farmers safeguard their crops, supply chains and personal safety. Forecasting plays a crucial role in enabling farmers to act before heat events cause irreversible damage.
This is the driving principle behind the “Early Warnings for All” initiative, led by WMO in collaboration with partners including FAO, which aims to transform climate data into actionable information.
Cambodia was highlighted as a positive example of this approach through its PEARL Project, supported by the Green Climate Fund and implemented by the Ministry of Agriculture, Forestry and Fisheries and the Ministry of Environment with technical backing from FAO. The project converts climate data into practical guidance for farmers, delivered via mobile applications and online platforms.
“Cambodia’s Green Climate Fund-funded PEARL project, supported by FAO, upgraded and installed new weather stations to feed a phone-based app that sends forecasts with crop- and region-specific guidance,” explained Zahedi.
The initiative is designed to support around 450,000 smallholder farmers in the northern Tonle Sap Basin by strengthening resilience to climate shocks through improved agrometeorological services, climate-smart agriculture and better market access. It also relies on coordinated data sharing between the Ministry of Water Resources and Meteorology and agriculture ministry to produce timely advisories.
Meas Pyseth, agriculture ministry secretary of state and national project director of PEARL, emphasised the importance of collaboration.
“Strong cooperation and data sharing among stakeholders are essential, as agrometeorological advisory services help smallholder farmers reduce climate related risks and achieve real impact,” he said.
When temperatures exceed 38°C, the system provides tailored advice such as maintaining soil moisture through mulching, shading crops, delaying rice planting and adjusting irrigation schedules to cooler periods of the day. It also promotes farmer safety by encouraging reduced physical labour during peak heat and ensuring access to water, shade and rest.
Despite the availability of such tools, the report warns that funding remains insufficient. In 2023, agrifood systems received only 4 per cent of total climate-related development finance. Without increased investment, early warning systems and support services will fail to reach the communities that need them most, particularly in rural areas often overlooked in climate planning.
The report concluded that preparing for extreme heat in advance is far more cost-effective than repeatedly absorbing losses. Strengthening resilience now can stabilise food production and prices while buying time for longer-term transformations in agriculture.
“We don’t need a new playbook. We need to use the one we already have. The FAO-WMO report lays out the risks of extreme heat. Now is the time to use that evidence to protect food systems and the people who sustain them,” explained Zahedi. - The Phnom Penh Post/ANN
