A few years ago, while doing research in the highlands of Ethiopia, a medical professional explained how cases of malaria were spreading each year up the mountains. Rising temperatures were allowing the parasite-carrying mosquitoes to survive at higher altitudes, and infect new communities. It is a story repeated across the world as we witness the impact of the climate emergency on global health ever more directly.
At COP28, the annual United Nations conference on climate change, which is underway in Dubai this week, a full day has been allocated to a discussion on the global health challenges of the climate emergency.
Whilst it might be the first time health has received such attention at a COP meeting, evidence for the impact of the climate emergency on health is clear and growing. The World Health Organization estimates that an annual 250,000 additional deaths will occur as a result of climate change-induced undernutrition, malaria, diarrhea and heat alone.
Climate change impacts on health in two main ways. Firstly, the direct impact from heatwaves, storms, floods and other extreme weather events. For example, the US city of Phoenix saw a 50 percent increase in heat-related deaths as a result of the summer heatwave that scorched large parts of America. As storms rage more intensely and frequently, as wildfires burn more often and across wider areas, as floods appear more suddenly, more people will be injured or killed as a result.
Secondly, climate change can exacerbate and spread existing diseases. Dengue fever, for example, was found in only nine countries in 1970. Now it is present in more than 100. Rising temperatures on land and sea can facilitate the spread of cholera and other diseases. Air pollution, which not only contributes to rising temperatures but is made worse by that increase, causes around 6.7 million deaths every year. Where food production is undermined by increased salinity in the soil as a result of rising sea levels, or too much heat or rain, it can lead to undernutrition and hunger.
Attention has only relatively recently turned to the impact of climate change on mental health, but it now appears that the scale of the problem is significant. The stress of living through climate emergency-linked disasters is a major cause of depression, post-traumatic stress disorder and anxiety. And a new term, “solastalgia” has been coined to describe the distress caused by witnessing and living through profound changes to the environments in which we live.
As climate change threatens health, the capacity of health systems to respond is also challenged by the worsening climate. Hit by two hurricanes in quick succession in 2017, one fifth of Puerto Rico’s health facilities in the most affected areas were severely damaged. Less than half of health facilities in neighboring Dominica were operational. In the Philippines, Super Typhoon Rai in 2021 damaged more than 220 health facilities in the space of a few hours. There is an urgent need to build greater resilience for health systems.
The terrible toll of the climate emergency on global health is clear and already occurring. But it is an unbalanced one, with poorer countries suffering the most despite contributing the least amount of harmful gases into the atmosphere. Those who are most vulnerable to the physical and mental health impacts are those contributing least to the processes that cause climate change. And as the temperatures rise, that toll increases inexorably.
Giving greater prominence to the health impacts of the climate emergency at COP28 is, then, long-overdue. The talks will be focusing on three important areas: how health systems can be made more resilient; increasing the proportion of climate financing targeted specifically at public health; and on mainstreaming health into climate policies.Â
But while these are all worthy goals, there are also some concerning gaps. The scale of financial resources needed to address the growing impact of climate change on health and health systems is immense. With the richer countries already reneging on previous promises of climate finance, few hold out hope of sufficient resources being made available in this round of talks.
The absence of a planned discussion during COP28’s health day on reducing fossil fuel use also feels like a missed opportunity.
 This matters because the same emissions that create climate change also have direct health impacts in their own right. Any delay to reducing reliance on fossil fuels and shifting to renewable energy will mean continued preventable deaths from those pollutants. Diarmid Campbell-Lendrum, head of the WHO Climate and Health team, has argued any delay will put such deaths in the millions.
While important, as critics rightly note, the focus on adaptation (how health systems can cope with climate change), should not come at the expense of an equally important and urgent debate on mitigation (how climate change can be slowed and reduced).
COP28 could be an important moment for integrating global public health into discussions, policy, and finance for climate change. And whatever the limitations of the discussion to be held on Sunday, it will hopefully lead to momentum in better integrating health into global and local responses to the climate emergency.Â
In the end it will be the phasing out of fossil fuels that will improve the health of us all, but especially the poor and most vulnerable who have done so little but are enduring so much of the climate emergency’s worst impacts.
Michael Jennings is a professor in global development at SOAS University of London, where he works on issues related to global health and the politics and history of global development. Twitter: @mikejennings101
