Heat-related deaths would increase by 370 per cent if the global temperatures continue to rise to under two degrees Celsius, a new report has revealed.

Titled the 2023 report of the Lancet Countdown on health and climate change: the imperative for a health-centred response in a world facing irreversible harms, the report says researchers and world leaders need to develop and implement evidence-based interventions to adapt to heat and reduce the worst of its impacts.

Apart from the deaths, the report indicates, heat-related labour loss is also projected to increase by 50 per cent and heat waves alone could lead to 524·9 million additional people experiencing moderate-to-severe food insecurity by 2041–60, aggravating the global risk of malnutrition.

Life-threatening infectious diseases are also projected to spread further, with the length of coastline suitable for Vibrio pathogens expanding by 17–25 per cent, and the transmission potential for dengue increasing by 36–37 per cent by mid-century. As risks rise, so will the costs and challenges of adaptation.

“The health risks of a two degree celsius hotter world underscore the health imperative of accelerating climate change action. With limits to adaptation drawing closer, ambitious mitigation is paramount to keep the magnitude of health hazards within the limits of the capacity of health systems to adapt,” reads part of the report.

Climate change action

With the world currently heading towards three degree celsius of heating, the report reveals that any further delays in climate change action threatens the health and survival of billions of people. The reason is climate change is increasingly impacting the health and survival of people worldwide and projections show these risks could worsen steeply with further inaction.

A study done between 2018 and 2022 shows that people experienced health-threatening heat for an average of 86 days each year. Climate change made it twice as likely for 60 per cent of these events to occur. Also heat-related deaths of people older than 65 years increased by 85 per cent compared with 1990–2000, substantially higher than the 38 per cent increase that would have been expected had temperatures not changed.

In 2023, the world saw the highest global temperatures in over 100, 000 years, and heat records were broken in all continents through 2022. Adults above 65 years and infants younger than one year, for whom extreme heat can be particularly life-threatening, are now exposed to twice as many heatwave days as they would have experienced in 1986–2005.

“Averting the worst impacts of climate change requires profound and immediate systemic changes. These changes must go beyond the treatment of the health symptoms of climate change, to put particular focus on primary prevention and rapidly accelerating mitigation efforts across all sectors, and ensure that climate change impacts stay within the bounds of the adaptive capacity of health and health-supporting systems.

Health promoting climate

According to the report, prioritisation of health in upcoming international climate change negotiations could offer an unprecedented opportunity to deliver health-promoting climate action and pave the way to a thriving future.

However, delivering such an ambition will require confronting the economic interests of the fossil fuel and other health-harming industries, and delivering science-grounded, steadfast, meaningful, and sustained progress to shift away from fossil fuels, accelerate mitigation, and deliver adaptation for health.

“Unless such progress materialises, the growing emphasis on health within climate change negotiations risks being mere health washing increasing the acceptability of initiatives that minimally advance action, and which ultimately undermine rather than protect the future of people alive today and generations to come,” reads the report.

“Safeguarding people’s health in climate policies will require the leadership, integrity, and commitment of the health community. With its science-driven approach, this community is uniquely positioned to ensure that decision makers are held accountable, and foster human-centered climate action that safeguards human health above all else.

The ambitions of the Paris Agreement are still achievable and a prosperous and healthy future still lies within reach. But the concerted efforts and commitments of health professionals, policy makers, corporations, and financial institutions will be needed to ensure the promise of health-centred climate action becomes a reality that delivers a thriving future for all,” the report added.