Report reveals the human cost of climate inaction

21 November 2023
Lancet report shows grave and mounting health impacts
New projections from the 2023 Lancet Countdown report reveals a world moving in the wrong direction on climate change, and how delayed action is a growing threat to our health

A global team of researchers, including from the University of Sydney have presented new findings, in the eighth annual global report of the Lancet Countdown on Health and Climate Change, with new global projections revealing the grave and mounting threat to our health from  delayed action on climate change.

One of the projections states if climate inaction continues - the world is likely to experience a three-fold increase in heat-related deaths by mid-century.

“Our health stocktake reveals that the growing hazards of climate change are costing lives and livelihoods worldwide today,” says Dr Marina Romanello, Executive Director of the Lancet Countdown at University College London.

“Projections of a 2°C hotter world reveals a dangerous future, and are a grim reminder that the pace and scale of mitigation efforts seen so far have been woefully inadequate to safeguard people's health and safety,”

“With 1,337 tonnes of carbon dioxide still emitted every second, we aren’t reducing emissions anywhere near fast enough to keep climate hazards within the levels that our health systems can cope with. There is an enormous human cost to inaction, and we can’t afford this level of disengagement – we are paying in lives. Every moment we delay makes the path to a liveable future more difficult and adaptation increasingly costly and challenging.”

Professor Ollie Jay, Dr Troy Cross and Associate Professor Ying Zhang from the University of Sydney’s Heath and Health Research Incubator were among the global team that contributed to the Lancet Countdown 2023 report.

Associate Professor Zhang worked to highlight regional perspectives in the global assessment, which includes Oceania. This is a new section of the report that provides a global comparison of the indicators across the regions to highlight the unequal health impacts of climate change, health inequity and various progress in climate action.

“Australia, in many ways, lags behind other comparable countries,” says Associate Professor Zhang.

“For example, in 2020, the region with the highest average energy sector emissions per person was Oceania (13.4 tonnes of CO2 per person), mostly driven by Australia. Oceania was also the second most affected region by droughts.

In a related commentary article, co-authored by Associate Professor Zhang and published in MJA today, the authors write that “Australia is clearly on the frontline of the climate change catastrophe. Australia's record 2017–2020 drought, the associated temperature and rainfall extremes, and the devastating Black Summer bushfires of 2019–2020 are stark indicators of things to come.”

Professor Jay and Dr Cross co-led the analysis of the Heat and Physical Activity Indicator  for the Global Report. This global indicator is based on the extreme heat risk assessment framework for sport that Professor Jay led the development of and is embedded within the Sports Medicine Australia Extreme Heat Policy launched in 2021.

Dr Cross developed the source code for analysing the geospatial data that served as the backbone for the Physical Activity indicator in the report.

“The new projections should serve as an alarm call for everyone – of the rapidly growing health hazards that people could be exposed to with climate change,” says Professor Jay.

“If the world continues to fail to curb emissions, and transition away from fossil fuels, these projected impacts on human health and wellbeing will be increasingly likely.”

Dr Cross says: “The findings of this year’s Lancet Countdown serve as a stark reminder that climate change is more than just an ecological concern – human health is under threat. In particular, our work on the Countdown (Physical Activity Indicator 1.1.3), and our recent work for the Climate Vulnerability Monitor (3rd Edition), together show that if we do not address climate change immediately, our ability to engage in physical activity, and thus our ability to work and exercise outdoors, will become increasingly threatened by growing amounts of exposure to conditions of serious heat-stress risk.”

Key findings

  • Climate inaction is costing lives and livelihoods today. In 2022, individuals were, on average exposed to 86 days of health-threatening high temperatures, 60 percent of those 86 days were at least twice as likely to occur because of human-caused climate change.
  • New global projections reveal the grave and mounting threat to health of further delayed action on climate change, with the world likely to experience a three-fold increase in heat-related deaths by mid-century.
  • A new regional section of the report highlights the unequal experience of the health impacts of climate change. This includes who is benefiting from climate change adaptation and the health co-benefits of the clean energy transition so far. The researchers outline the opportunity that a just energy transition offers to reduce health inequities and improve the health and wellbeing of all populations.
  • Data from this year’s report reveal a world moving in the wrong direction. Governments, companies, and banks continue investing in oil and gas as the challenges and costs of adaptation soar, and the world approaches irreversible harm.
  • Without profound and swift mitigation to tackle the root causes of climate change, the health of humanity is at grave risk. The stark findings must force urgent health-centred climate action to shift the global economy to a zero-carbon footing while delivering transformative opportunities to improve the health of world populations through improved energy access and security, cleaner air, safer drinking water, healthier diets and lifestyles, and more liveable cities.

Health-centred climate action needed

The failure to seriously address climate change is evident in the report, with health-related losses and damages soaring globally.

The report is launching ahead of the 28th UN Conference of the Parties of the UNFCCC (COP28), which will for the first-time feature health as a key theme, with an official Health Day and a climate-health ministerial.

The Lancet Countdown report contributes to the evidence needed to inform the negotiations and deliver truly health-protecting climate change action. 

Responding to the report publication, UN Secretary-General, António Guterres (who was not involved in writing the report) says:

 “We are already seeing a human catastrophe unfolding with the health and livelihoods of billions across the world endangered by record-breaking heat, crop-failing droughts, rising levels of hunger, growing infectious disease outbreaks, and deadly storms and floods.,

“The continuing expansion of fossil fuels is a death sentence to millions. There is no excuse for a persistent delay in climate action. Temperature rise must be limited to 1.5°C to avert the worst of climate change, save millions of lives, and help protect the health of everyone on earth.”

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Matt Johnston

Assistant Media and PR Adviser (Health and Medicine)

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