Heat related deaths to see an almost fivefold jump by midcentury, Lancet study reveals

Annual heat-related deaths might see an almost fivefold jump, if the global mean temperature continues to rise just below 2°C, a recent report reveals.

This year, the world experienced the highest global temperatures in over 100,000 years, with heat records shattered across all continents throughout 2022 as extreme weather events occurred in every continent.

These findings have been published in the 2023 edition of the Lancet Countdown on Health and Climate Change which underscores the serious and escalating risk to health posed by prolonged inaction on climate change. 

This year, the report relies on the collective expertise of 114 scientists and health practitioners representing 52 research institutions and UN agencies globally, offering its most comprehensive assessment to date.

Today, the climate is 1.4°C hotter than it was in pre-industrial times because of human activities. Dr Marina Romanello, executive director of the Lancet Countdown, suggests that these factors related to climate change are directly undermining the foundations that define good health and well-being. 

Extreme heat exposure and other extreme weather events have undermined food security around the world and have resulted in an increase in the spread of infectious diseases.

“Even at that temperature rise, we can see that climate change is impacting people’s health all around the world and in every country,” said Dr Romanello.

“It’s ultimately affecting our physical and mental health through several interconnected pathways and is a continually growing trend, that we are registering year-on-year, and we know that climate change is behind it.”

The report highlights how inaction towards climate change has taken a toll on health worldwide, and calls out governments, oil and gas companies, amongst others, who are responsible for the collective and irreversible harm that is being done to the environment. 

“Oil and gas companies have continued to expand their production plants, and are now on track to exceed the emission levels compatible with a livable future by 173%, which is an increase from the 112% we were expecting last year,” said Dr Romanello.

Private funders continue to finance oil and gas companies, and subsidies from governments support their expansion. The Lancet Countdown report for 2022 emphasized the chance to expedite the shift away from harmful fossil fuels amid the global energy crisis. Nonetheless, the data this year reveals that we are no closer to achieving that goal and in fact are heading in the opposite direction.

This is reflected in the record profits being raked in by oil and gas companies. Alarmingly, these companies are diminishing their adherence to the Paris Agreement even further, according to Dr Romanello. 

Researchers also call attention to the inaction of fossil fuel companies, stating that instead of prioritizing the rapid advancement of renewable energy, these companies directed only 4% of their capital investment towards renewables in 2022. 

All of these impacts are cascading towards our economies. 

For the year 2023, the report projects an increase in heat-related labor loss at 50%, and states that heatwaves alone could result in an additional 524.9 million people facing moderate to severe food insecurity by 2041–60, exacerbating the global risk of malnutrition.

“Labor productivity is being impaired by exposure to extreme heat. Poor workers that are exposed to the elements, agricultural workers, construction workers, especially in the lower Human Development Index (HDI) countries, are the most affected,” said Dr Romanello.

“We’re seeing today that more labor hours, about 42%, are lost as compared to the 1990s, and that has come at an enormous cost in terms of people’s wealth and income. We estimate that more than $100 billion were lost in 2022 alone as a result of that labor capacity loss.”

As health considerations take on greater importance in climate change negotiations, this report highlights opportunities to implement climate change actions that promote health and contribute toward securing our future. 

The estimates offered provide a glimpse into potential future scenarios. The researchers note, however, that incomplete consideration of non-linear responses, tipping points, and cascading and synergistic interactions may render these projections conservative, thus heightening the threat to the health of populations worldwide.

“We are now able to understand where the hands of climate change are playing a role, in our exposure to health harms,” said Dr Romanello. 

“We have a choice to make, we have an opportunity to tackle emissions today, to increase our adaptation efforts and to ensure that we do not head down that road which could be catastrophic.”