climate and health

More frequent heatwaves could lead to around 525 million more people experiencing moderate to severe food insecurity by 2041-2060, exacerbating the global risk of malnutrition. Photo: Trinity Care Foundation

Health risks soaring in the face of climate inaction globally: Lancet report

New global projections reveal the mounting threat to health due to further delayed action on climate change, with the world likely to experience a 4.7-fold increase in heat-related deaths by mid-century 

Climate inaction is costing lives and livelihoods today. In 2022, individuals were, on average, exposed to 86 days of health-threatening high temperatures, of which 60% were made at least twice as likely to occur because of human-caused climate change. The findings of the 2023 Report of The Lancet Countdown on Health and Climate Change shed light at the catastrophic threat to the health and survival of billions of people all over the world, and to successful adaptation efforts, from any further delays in action to limit temperature increase to 1.5°C above pre-industrial levels. 

With the world currently on track for 2.7°C of heating by 2100, and energy-related emissions reaching a new record high in 2022, the lives of current and future generations hang in the balance. 

“Our health stocktake reveals that the growing hazards of climate change are costing lives and livelihoods worldwide today. Projections of a 2°C hotter world reveal 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,” says Dr Marina Romanello, executive director of the Lancet Countdown at University College, London. “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.”  

The report presented 47 indicators that include metrics that monitor household air pollution, financing of fossil fuels, and engagement from international organisations on the health co-benefits of climate mitigation. 

Mounting health and livelihood concerns fueled by climate inaction

The report found that the increasing destructiveness of extreme weather events jeopardises water security and food production, putting millions at risk of malnutrition. More frequent heatwaves and droughts were responsible for 127 million more people experiencing moderate to severe food insecurity in 122 countries in 2021, than annually between 1981 and 2010. 

Even at the current 10-year global average 1.14°C of heating, people experienced on average 86 days of health-threatening high temperatures in 2018-2022, more than 60% of which were made more than twice as likely to occur because of man-made climate change. Heat-related deaths in people aged over 65 increased by 85% in 2013-2022 compared to 1991-2000, substantially above the 38% increase expected had temperatures not changed (i.e., accounting only for changing demographics). 

Similarly, changing weather patterns are accelerating the spread of life-threatening infectious diseases. For example, the report said, warmer seas have increased the area of the world’s coastline suitable for the spread of Vibrio bacteria that can cause illness and death in humans by 329km every year since 1982. This  puts a record 1.4 billion people at risk of diarrhoeal disease, severe wound infections, and sepsis. The threat is particularly high in Europe, where Vibrio-suitable coastal waters have increased by 142km every year, the report warned.  

Healthcare systems are the first line of defense for protecting people from the growing health harms from the changing climate. But even the current 1.14°C of heating is putting serious pressure on health services, with 27% (141/525) of surveyed cities reporting concerns over their health systems being overwhelmed by the impacts of climate change. 

The report found that the total value of economic losses resulting from extreme weather events was estimated at $264 billion in 2022, 23% higher than in 2010-2014. Heat exposure also led to 490 billion potential labour hours lost globally in 2022 (a nearly 42% increase from 1991-2000), with income losses accounting for a much higher proportion of GDP in low- (6.1%) and middle-income countries (3.8%). These losses increasingly harm livelihoods, restricting the capacity to cope and recover from the impacts of climate change. 

In India, the potential labour hours lost due to heat exposure in 2022 stood at 191 billion, an increase of 54% from 1991-2000, leading to a  potential associated income loss of $219 billion in 2022, equivalent to 6.3% of GDP.

New projections: Scary future ahead, urgent mitigation needed

New projections outlined the rapidly growing risks to population health if the 1.5°C target is missed, with every health hazard monitored by The Lancet Countdown predicted to worsen if temperatures rise to 2°C by the end of the century.

Under this scenario, yearly heat-related deaths are projected to increase by 370% by mid-century, with heat exposure expected to increase the hours of potential labour lost globally by 50%. More frequent heatwaves could lead to around 525 million more people experiencing moderate to severe food insecurity by 2041-2060, exacerbating the global risk of malnutrition. Life-threatening infectious diseases are also projected to spread further by mid-century.

Wrong move: Subsidising fossil fuels  

The data from the report revealed that investment and lending on fossil fuels are on the rise. In 2020, 69 of 87 countries (responsible for 93% of all global carbon emissions) provided fossil fuel subsidies to the net value of $305 billion—exceeding 10% of national health spending in 26 of the countries, and 50% in 10 countries. 

The finance sector is also contributing to growing health threats, with total private bank lending to fossil fuels reaching $572 billion in 2017-2021. Together, the world’s 20 largest oil and gas giants have increased their projected fossil fuel production levels since last year, which would result in greenhouse gas emissions surpassing levels compatible with 1.5°C of warming by 173% in 2040. To make matters worse, the report noted, fossil fuel companies allocated just 4% of their capital investment to renewables in 2022.

Despite plentiful natural renewable energy resources, just 2.3% of electricity comes from clean renewables in low-income countries (compared with 11% in wealthy countries); and 92% of households still rely on polluting biomass (such as wood or dung) to cook and heat their homes (compared with 7.5% in rich nations). 

Transformative opportunities of health-centred climate action

“Empowering countries to transition from dirty fuels towards local, modern renewable sources of energy, would not only bring immediate health benefits, but also reduce socioeconomic and health inequities, by developing local skills, generating jobs, supporting local economies, and delivering energy to off-grid areas to electrify homes and health-care facilities, particularly in areas where energy poverty still undermines people’s health and wellbeing”, says Ian Hamilton, Lancet Countdown Working Group Lead on Mitigation Actions and Health Co-benefits.  

Improvements in air quality could prevent many of the 1.9 million deaths every year coming directly from exposure to fuel-derived outdoor air pollution, and millions more from indoor air pollution. Shifting to accessible active, public, and electric travel could avert many of the 460,000 deaths caused annually by travel-related PM2·5 emissions, while improving health by supporting physical activity. 

The report recommended accelerating a transition to healthier, low-carbon diets that could prevent up to 12 million deaths due to poor diets every year, as well as reduce 57% of agricultural emissions from dairy and red meat production. This would also deliver healthier populations, reduce pressures on health systems, help minimise healthcare-related emissions, and promote health equity. 

All is not lost

Slowly but surely some progress is being made. The report revealed that deaths from fossil fuel-derived air pollution have fallen almost 16% since 2005, with 80% of this decline due to efforts to reduce pollution from coal burning. 

At the same time, global investment in clean energy grew 15% in 2022 to $1.6 trillion, exceeding fossil fuel investment by 61%, while lending to the green energy sector rose to $498 billion in 2021, approaching fossil fuel lending. As a result, renewable energy accounted for 90% of the growth in electricity capacity in 2022, and employment in renewables reached a record-high with 12.7 million employees in 2021. 

Responding to the report publication, UN Secretary-General, António Guterres (who was not involved in writing the report) said, “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.” 

The ask from COP28

“The health focus at COP28 is the opportunity of our lifetime to secure commitments and action. If climate negotiations drive an equitable and rapid phase out of fossil fuels, accelerate mitigation, and support adaptation efforts for health, the ambitions of the Paris Agreement to limit global heating to 1.5°C are still achievable, and a prosperous healthy future lies within reach. Unless such progress materialises, the growing emphasis on health within climate change negotiations risks being just empty words, with each fraction of a degree of heating exacerbating the harms felt by billions of people alive today and the generations to come, ” added Dr Romanello.