Opinion: Climate action is a global health opportunity

The links between climate change and health are increasingly being recognized, and there has been more discussion about these in and around COP 27 than at previous COPs. Despite this, health still hardly features in climate policies, targets, and negotiations. It’s time this changed.

The agreement reached at the 27th United Nations Climate Change Conference of the Parties on setting up a “loss and damage” fund — a form of climate reparations — is an important step toward supporting climate-vulnerable countries. But, critically, the conference has done little to address the root causes of climate change and limit global heating through the rapid phase-out of fossil fuels.

Several scientific reports published on the eve of COP 27 reiterated the scale of the impacts of climate change on human health and the inadequacy of the global response. According to the latest United Nations Environment Programme Emissions Gap report, the international community is not on track to achieve the Paris Agreement goals and with no credible pathway to 1.5 degrees Celsius currently in place, urgent action is needed to avert catastrophe.

So why is our response to this climate emergency so sluggish? A major factor explaining this may be that in most high-income countries, the tangible impact on people’s lives has, until recently, felt relatively small. The devastating effects of climate change are disproportionately affecting low- and middle-income countries, especially vulnerable populations within those countries.

But it is becoming increasingly evident that no part of the world is immune. People living in high-income countries are now starting to experience more extreme weather events such as heat waves and floods. Infectious diseases are spreading further and faster due to warming temperatures, as we saw with the recent outbreak of dengue in France. The impact of climate change on our lives and livelihoods is no longer far away in time or distance but right here, right now.

Graphs of rising carbon dioxide levels in the atmosphere or temperatures may be useful to explain the physics of climate change. But when people see these skyrocketing, do they also see increasing human suffering, disease, and premature death?

With COVID-19, people saw growing infection rates and understood the health implications this might have for them, their families, and their neighbors. The need for rapid global emergency response was widely accepted and the scale and extent of control measures were unprecedented. The threat of climate change to human health must be treated with as much — if not more — gravity and urgency as COVID-19 by all of us.

Climate change is impacting health through many different pathways. First, there are direct effects: For example, increased deaths during heat waves. More than a third of the heat-related deaths between 1991-2018 were estimated to be attributable to climate change.

Second, there are indirect effects mediated through changes in ecosystems. An example is the increased number of people who will be at risk of malaria and dengue because of the growth in supportive habitats for mosquitoes and the increase in human populations. Even at current levels of warming — an increase of 1.2 degrees Celsius by 2100 — there will be at least an additional 2.4 billion people at risk and, if the temperature rises by 3.5 degrees  Celsius, this will almost double to an additional 4.7 billion people at risk.

Third, there are indirect effects on health through socioeconomic factors, such as increased poverty caused by declining manual labor productivity in conditions of extreme heat. If the global average temperature increase reaches 2.5 degrees Celsius, about 1 billion people will be unable to work safely during at least the hottest month of the year.

In the wake of COP 27, the health argument for climate action has never been clearer. We need to mitigate, rapidly cut fossil fuel burning and produce healthy food sustainably to address the major driving forces of climate change.

That said, even the most optimistic projections for mitigation will see substantial changes to our climate continue, translating into ill health and death for populations most affected, who are often those with the least resilience. So we also need to rapidly adapt to reduce human suffering, and wealthier nations must deliver adequate financing for climate-vulnerable countries to cope with impacts that cannot be avoided.

Research is already providing the evidence needed to drive and inform action. Many interventions have major co-benefits, reducing greenhouse gas emissions while also improving health through cleaner air, healthier diets, and more active communities.

Recent evidence suggests, for example, that improved air quality through fossil fuel phase-out could have prevented 1.2 million deaths in 2020 alone. Accelerated transition to balanced and more plant-based diets would reduce agricultural sector emissions from red meat and milk production, while preventing up to 11.5 million diet-related deaths annually and reducing the risk of zoonotic diseases.

Before we have even recovered from COVID-19, the world is facing new instability with energy, food, and a cost of living crisis. Addressing the threat to human health from climate change is an opportunity to tackle multiple interconnected global crises at once.

With growing evidence of the health harms of climate change and the health benefits of climate action, it is our duty to continue pushing for health to be at the heart of climate change policies, negotiations, and solutions.

Visit the Planet Health series for more in-depth reporting on the current impact of the climate crisis on human health around the world. Join the conversation by using the hashtag #PlanetHealth.