Introduction
Rising heatwaves impacts are increasingly affecting millions across the globe. As climate change accelerates, heatwaves are growing more frequent, intense, and deadly [1][2][3]. Vulnerable groups—older adults, outdoor workers, and those with chronic illness—bear the brunt, often without warning or protection.
What exactly are scientists finding? How is daily life changing under the heat? And how can communities adapt before it’s too late?
How Much Worse Are Heatwaves Getting
WHO reports that extreme heat events are rising in frequency, duration, and intensity. Between 2000 and 2016, some 125 million more people were exposed to heatwaves globally compared to previous decades [1].
The 2023 Lancet Countdown shows that global temperatures have reached unprecedented highs, pushing heat-related illness and mortality into more regions than ever before [2]. In Europe alone, more than 60,000 deaths in 2022 and tens of thousands more in 2023 were linked directly to extreme heat [1][2].
Similar patterns are emerging elsewhere. Meanwhile, in India and Pakistan, springtime heatwaves often exceed 45°C, straining hospitals and reducing crop yields. In the United States, extreme heat is already the leading weather-related killer, surpassing hurricanes and floods. In Africa, longer dry seasons put pressure on agriculture and water resources. As a result, food insecurity deepens.”.
Impacts on Health, Labour, and Daily Routines
Health Consequences
Heat rarely kills directly. However, it worsens existing conditions. Heatwaves intensify heart, lung, and kidney diseases and can trigger strokes [1]. High night-time temperatures reduce the body’s ability to recover, compounding risks for those with chronic illness.
Lost Work & Productivity
In 2023, more than 500 billion potential work hours were lost globally due to heat stress, particularly in agriculture and construction [2]. For millions, this means lost wages, less food security, and deeper poverty.
Everyday Life Disruption
Daily routines are shifting. Outdoor workers alter schedules. At the same time, schools cut recess, and transport systems falter as infrastructure buckles. Unrelenting night-time heat disrupts sleep. Therefore, it lowers productivity and mental health [3]. Even cultural life—festivals, sports, outdoor gatherings—is increasingly curtailed.
Who Is Most at Risk
- Elderly people, especially those without cooling.
- Outdoor workers in construction, farming, and delivery.
- Urban residents in “heat islands” with little shade or green space.
- People with chronic illness, as heat worsens underlying conditions [1].
In many low-income communities, lack of air conditioning or affordable electricity makes adaptation nearly impossible. Migrant workers, often in crowded housing, are also highly vulnerable.
What Needs to Change
Addressing rising heatwaves impacts requires a comprehensive response that blends immediate adaptation with long-term climate action. Governments must strengthen early warning systems and ensure cooling shelters, water stations, and public alerts reach the most vulnerable. In addition, urban areas should be redesigned with more trees, reflective surfaces, and shaded spaces to counter the heat-island effect, while workplaces—particularly in agriculture and construction—need protections such as flexible hours, mandated breaks, and hydration support. At the same time, health systems must expand their capacity to treat heat-related illness and educate communities about prevention. Ultimately, reducing greenhouse gas emissions remains critical; without cutting the drivers of climate change, every adaptation measure will be outpaced by intensifying heatwaves.
A One Health Perspective on Rising Heatwaves Impacts
A One Health lens shows how heatwaves intersect human, environmental, and urban health. Green spaces, shaded infrastructure, and clean air reduce both heat stress and pollution. Cooling centers and early warning systems protect vulnerable groups.
Heat also stresses crops and livestock, threatening food security. Urban design—tree cover, reflective roofing, sustainable water systems—can reduce temperatures while boosting public health [1][2]. Cutting emissions not only slows global warming but also improves air quality, saving lives now and in the future.
Conclusion
Rising heatwaves impacts are not just future threats—they are already reshaping daily life. With more people exposed to extreme heat, the world is seeing higher death tolls, massive productivity losses, and disruption to work, school, and health.
By protecting vulnerable populations, redesigning cities, and cutting emissions, societies can reduce the toll of the silent killer. Without action, the impacts of rising heatwaves will intensify, forcing millions into hotter, deadlier futures.
References
- World Health Organization (WHO) (n.d.). Climate change and health. Available at: https://www.who.int/news-room/fact-sheets/detail/climate-change-and-health
- The Lancet Countdown on Health and Climate Change (2023). 2023 Report. Available at: https://lancetcountdown.org/2023-report/
- The Guardian (2025). The silent killer: what you need to know about heatwaves. Available at: https://www.theguardian.com/environment/2025/jun/27/the-silent-killer-what-you-need-to-know-about-heatwaves
- WHO Europe (2023). Heat-related mortality in Europe. Available at: https://www.who.int/europe/news-room/fact-sheets/item/climate-change
