Extreme heat is now the deadliest climate hazard, causing an estimated half a million deaths worldwide each year, most of them in low- and middle-income countries. Beyond its toll on ecosystems and human health, rising temperatures are also reshaping economies by disrupting supply chains and the conditions under which people work. The final Cool Talk of 2025 focused on the impacts of heat stress on the labour-intensive apparel sector, where new findings show that export earnings in key producing countries could be reduced by up to USD 65.8, resulting in one million fewer new jobs by 2030. The webinar unpacked The Heat is On, a new research note jointly prepared by Cornell University’s Global Labor Institute and the International Finance Corporation (IFC), with input from the International Labour Organization’s Better Work team, examining how extreme heat and flooding are already affecting a USD 1.77 trillion industry and its 90 million workers.
Opening the discussion, Marisofi Giannouli, Communications Lead of the UNEP Cool Coalition, situated the findings of The Heat is On within the broader political moment following the 2025 UN Climate Change Conference (COP30) in Belém. She reflected on a moment shaped quite literally by record heat, underscoring that the world is now operating in an overshoot reality, where climate impacts are no longer abstract but immediate and structural. Against that backdrop, she highlighted COP30 as a turning point for sustainable cooling, marked by two defining moments: the launch of Beat the Heat, a national-to-local implementation drive mobilising cities to address extreme heat where it hits hardest, and the second Cooling Ministerial, underpinned by the newly released Global Cooling Watch 2025, which anchored political commitments in robust, updated science. Giannouli emphasised that progress on cooling is no longer driven by universal consensus, but by leadership from those ready to act. “What we are seeing now is a coalition of the willing,” she noted, “moving forward with solutions that are grounded in evidence, delivered locally, and scaled through collective action.”
The panel was moderated by Sabine Hertveldt, IFC Senior Operations Officer for Manufacturing, Agribusiness and Services, who framed the apparel sector as an early indicator of how climate impacts are playing out across manufacturing, where margins are thin, production schedules are rigid, and workers have little room to absorb additional stress.
Jason Judd, Executive Director of Cornell University’s Global Labor Institute, kicked off the panel discussion by walking participants through the analytical backbone of the research note. Drawing on factory-level temperature data and physiological thresholds, he showed that worker productivity begins to decline well before conditions become extreme. “For every one-degree Celsius increase in wet bulb temperature above 25 degrees, productivity in apparel manufacturing falls by about 1.5 percent,” Judd explained. He noted that during peak heat periods, these incremental losses compound, resulting in significant reductions in output even when factories remain operational. Judd also highlighted elevated night-time temperatures as particularly damaging, as they prevent physical recovery between shifts, compounding fatigue and injury risk over time. In parallel, he underscored flooding as a major disruption risk, explaining that even short flood events can shut down production for days or weeks, damage inputs, and cascade through global supply chains.
Where Jason Judd laid out the scale and mechanics of climate risk from a research perspective, Jens Aas, Senior Manager for Worker & Community Development and Supply Chain Sustainability at VF Corporation, translated those findings into operational reality. Speaking from the standpoint of a global apparel company sourcing from around 40 countries, Aas explained how climate adaptation is now moving to the centre of supply-chain management, alongside mitigation. He outlined VF’s factory standards, which set clear temperature thresholds for compliance, require adequate ventilation and airflow, and trigger corrective action plans when conditions exceed safe limits or fall short of local regulations. Beyond audits, he highlighted VF’s investments in worker wellbeing through water, sanitation and hygiene programmes in high-risk countries such as Bangladesh and Cambodia, including guaranteed access to safe drinking water, adjusted work-rest schedules during extreme heat, and worker training on heat-stress prevention. “What this research helps us do,” Aas noted, “is connect climate impacts directly to productivity, risk and worker wellbeing, making it much easier for companies to act and scale solutions.”
Rounding up the panel, IFC Global Cooling Lead Rusmir Musić focused on how solutions can be financed and scaled. “Cooling is not just about comfort,” he noted. “It is about protecting productivity, safeguarding assets, and making businesses resilient to future climate shocks.” Musić presented IFC’s Sustainable Cooling Initiative 5×5 approach, which targets five high-impact sectors including manufacturing, agribusiness, cold chains and green buildings, delivered through five engagement pillars designed to mobilise capital, reduce risk and accelerate market uptake. With support from the UK Government, IFC is providing technical assistance, market matchmaking and financing solutions that help companies move beyond conventional air conditioning toward passive and low-energy cooling. Musić highlighted tools such as IFC’s EDGE certification, which allows firms to model future heat stress and cooling loads, and the Building Resilience Index, which helps companies assess physical climate risks and link resilience investments to access to green finance.
During the keynote intervention, Lun Lido, Chief of Policy and Coordination Office at Cambodia’s Ministry of Environment, gave a national perspective on how extreme heat is rapidly becoming a development risk for the country, particularly for workers in apparel, construction, agriculture, market vendors, waste collectors, and the informal sector. He noted that Cambodia is experiencing some of the fastest-rising temperatures in Southeast Asia, with heat index levels exceeding 40 °C in recent years, triggering school closures and public health warnings. In response, Cambodia is prioritising sustainable cooling through its Climate Change Strategic Plan 2024–2033, NDC 3.0 and its National Cooling Action Plan (NCAP), placing emphasis on passive cooling and energy efficiency before turning to mechanical air conditioning. Mr. Lido highlighted pilot projects showing that passive cooling measures can lower indoor temperatures by up to 7 °C while significantly reducing electricity use, with this evidence now informing building regulations and public procurement. “Cambodia’s approach is to reduce cooling demand first, by design, before adding any mechanical systems,” he said. He underscored that scaling these solutions will require clearer labour guidance on heat protection, stronger partnerships across government, the private sector, and the development partners, as well as sustained financial and technical support.
Across research, industry practice, finance and public policy, all speakers converged on the fact that protecting workers and supply chains in a warming world requires moving cooling from a technical afterthought to a core element of climate adaptation and delivery. The UNEP Cool Talks series will return on 22 January 2026 to introduce a new global database of cooling innovators.