The warming effects of climate change have seen the rate of heat-related deaths surge 23% since the 1990s - to over 546,000 a year - according to the ninth Lancet Countdown Report on Health and Climate Change.
This year's report said the continued overreliance on fossil fuels and failure to adapt to climate change is being paid for in people’s lives, health and livelihoods, with 13 of the 20 indicators tracking health threats reaching unprecedented levels.
The report said that in 2024, air pollution from wildfire smoke was linked to a record 154,000 deaths.
The global average transmission potential of dengue, a viral infection spread by mosquitoes, has also risen 49% since the 1950s.
Air pollution resulting from the continued burning of fossil fuels has resulted in 2.5 million deaths every year, the authors of the report said.
On a positive note, the report said the global momentum for climate change action is already seeing positive benefits. Between 2010 and 2022, an estimated 160,000 premature deaths yearly were prevented by shifting away from fossil fuels, according to the report.
But it also points to a "political backsliding" on climate and health action threatens to condemn millions to a future of disease, disasters and early death.
It said emboldened by growing profits and a fractured political consensus on climate commitments, oil and gas giants continue to expand their production plans - to a scale three times greater than a liveable planet can support, creating a vicious cycle that harms the planet and people’s lives.
In this challenging environment, it said local governments, individuals, civil society and the health sector are leading the way in shaping a healthier future, signalling what will be the start of transformative climate action.
As the international community is set to meet at COP30 in Belem, Brazil, the report calls for an all hands on deck approach to accelerate progress.
It said that high greenhouse gas-emitting countries and their corporations must urgently reduce their emissions to prevent climatic changes exceeding the capacity to adapt.
As the upcoming COP is set to focus on adaptation, the report said delivering this health-protecting transformation requires unity and concerted efforts, and support from all sectors of society.
The report said that climate change driven by human-caused greenhouse gas emissions is increasingly claiming lives and harming people's health worldwide.
Mean annual temperatures exceeded 1.5C above those of pre-industrial times for the first time in 2024.
Research published in July 2024 by the Economic and Social Research Institute (ESRI) in Ireland and funded by the Irish Heart Foundation and Irish Cancer Society on behalf of the Climate and Health Alliance, provided evidence on the link between climate change, temperature changes and health and healthcare utilisation in Ireland.
It said that climate change has direct and indirect impacts on population health.
Temperature increases are considered one of the principal threats to population health associated with climate change in Ireland.
The ESRI report found that over the period 2015-2019, emergency hospital admissions for temperature-affected diseases were 8.5% higher on hot days (22–25C) compared to moderate temperature days (10–13C) in Ireland.
The largest increases in hospitalisations on hot days were seen for circulatory, respiratory and infectious diseases, and among younger people (0-14 years).
Govt must clarify if heat-related deaths are being recorded - O'Gorman
Green Party Leader Roderic O'Gorman said the Irish Government must clarify if it is recording heat-related climate deaths.
"Climate change is altering our weather patterns. It is making our summers hotter, which has significant impacts for people with vulnerable or pre-existing health conditions. Hotter nights mean people's sleep is disturbed.
"High temperatures outside mean that people can't exercise," Mr O’Gorman said.
He said that in July of this year, he put in a Dáil question to Minister for Health Jennifer Carroll MacNeill if the HSE collects statistics on the number of heat-wave related deaths per year and to provide any such statistics from 2010 to 2024.
Mr O'Gorman said he is still waiting to hear back from the HSE.
"If you can’t measure something, you can’t manage it. How can we understand how we can reduce climate change related heat deaths in Ireland, if Government isn’t producing clear statistics," Mr O’Gorman said.
