From farms to factories, rising temperatures are cutting productivity and endangering lives, with the poorest paying the highest price. Half the world is already struggling with the effects of extreme heat, according to a joint report from the World Health Organization (WHO) and the World Meteorological Organization (WMO) published on Friday. The collaborative guidance sets out recommendations for companies and governments as climate change – and heat stress in particular – upends the world of work. “Extreme heat is a public health crisis,” said Rüdiger Krech, WHO director of environment, climate change and health, during a Thursday briefing. “It is already harming the health and livelihoods of billions of workers across the world.” The warning comes as the WMO confirmed that 2024 was the warmest year on record, with global temperatures averaging 1.45°C above pre-industrial levels. The past decade has been the hottest in human history. The 2025 summer season saw temperatures ...