Climate Change Linked to Nearly 100,000 Deaths in 2023 Heatwaves – News Today | First with the news

New global evidence points to an alarming toll from last year’s extreme heat: close to 100,000 deaths during the 2023 heatwaves are estimated to have been driven by human-caused climate change. Researchers examining mortality across 2,013 communities in 67 countries concluded that just over half of the 178,486 excess deaths recorded during the most punishing heat periods — equivalent to roughly 23 deaths per million people — can be attributed to the warming influence of greenhouse gas emissions. The findings arrive in the context of the hottest year ever measured, with average global temperatures sitting about 1.45°C above pre-industrial levels.

Key takeaways from the analysis

• Scope: Mortality data spanned 2,013 locations in 67 countries, capturing a wide range of climates and health systems.
• Excess deaths: 178,486 more deaths occurred during intense heat than would normally be expected.
• Attribution to climate change: Approximately 54% of those excess deaths — nearly 100,000 people — are linked to human-driven warming.
• Population-level impact: The burden translates to about 23 heat-attributable deaths per million people.
• Context: The analysis coincided with 2023 being the hottest year on record, at roughly 1.45°C above pre-industrial temperatures.

How extreme heat claims lives

Heat is a stealth hazard. It strains the heart and lungs, disrupts the body’s ability to regulate temperature, worsens dehydration and electrolyte imbalances, and can trigger kidney stress and heat stroke. Nights that remain hot compound the danger by eliminating the body’s chance to cool down. Urban environments intensify exposure through heat-trapping concrete, minimal shade, and limited ventilation — a phenomenon known as the urban heat island effect. When heat combines with poor air quality, the health risks grow, especially for those with pre-existing conditions.

Who is most vulnerable

• Older adults and people with cardiovascular, respiratory, or renal illnesses face higher risk.
• Outdoor and manual workers, as well as those in factories or warehouses without adequate cooling, are disproportionately exposed.
• Low-income households often lack access to air conditioning or live in poorly insulated homes that trap heat.
• Children, pregnant people, and individuals taking certain medications can be more sensitive to heat stress.

What the numbers mean for cities and health systems

The scale of heat-related mortality in 2023 underscores the need for comprehensive heat preparedness. Public health agencies and local governments can reduce risk through early warning systems, neighborhood-level alerts, and clear guidance on hydration, rest, and recognizing heat illness. Targeted outreach to vulnerable groups — including wellness checks and transport to cooling centers — can save lives. Retrofitting homes and public buildings with better insulation and passive cooling, expanding urban tree canopy, and using reflective roofing and paving materials help lower ambient temperatures. Employers can protect workers by adjusting schedules, mandating shaded rest breaks, and ensuring access to water.

Hospitals and clinics should anticipate heat surges with surge staffing, cooling protocols, and rapid triage for heat-related illness. Community organizations can assist with distributing fans, facilitating access to cooling centers, and coordinating neighbor-to-neighbor support during extreme heat events.

A global challenge with local solutions

While certain regions are accustomed to hot seasons, the pace and intensity of recent heatwaves are pushing into new territory, including in places once considered temperate. Demand for cooling is rising rapidly, but widespread air conditioning without efficiency improvements and cleaner power risks increasing emissions and straining electricity grids just when they are needed most. Scaling up energy-efficient cooling technologies, improving building codes, and expanding access to clean, reliable power are critical to keep people safe without deepening the problem.

Reducing risk at the source

Adaptation measures can prevent many deaths, but they work best alongside rapid, sustained cuts in climate pollution. The evidence that human-driven warming intensified 2023’s deadly heat highlights the importance of accelerating the transition to low-carbon energy, improving public transport and active mobility, and protecting and restoring ecosystems that cool cities and regions. Each fraction of a degree avoided reduces the probability of deadly heat extremes.

The bottom line

The toll from 2023’s heatwaves is a stark warning. With global temperatures already elevated, extreme heat is no longer a rare emergency but a recurring public health threat. The findings show that many of these deaths were not inevitable: they were amplified by a warmer climate and can be reduced through smarter planning, strong social protections, and decisive climate action. Lives can be saved — but only if the lessons from 2023 are turned into concrete steps before the next heatwave arrives.