Every Saturday we decipher climate issues with François Gemenne, professor at HEC, president of the Scientific Council of the Foundation for Nature and Man and member of the IPCC. Saturday November 18: the heat wave hitting Brazil.
The figures are dizzying: up to 58° in temperature felt in recent days in Brazil, with temperature differences up to 5° above the average, and temperatures which reached 39° in several places of the country, which actually gives this impressive felt temperature, and which obviously brings very serious health issues, which have just been recalled in the “Lancet Countdown”, the annual report of the medical journal The Lancet dedicated to climate.
Every year, The Lancet indeed devotes a large report to the health dimensions of climate change, and the 2023 edition has just been released. This is interesting, because it reflects the increasing engagement of health professionals around climate change. And it is also true in the other direction: for the first time, COP28 will have a day dedicated to health.
It must be said that the health impacts of climate change are very numerous: there is obviously excess mortality linked to extreme phenomena, and in particular heat waves. The report of Lancet tells us that heat-related mortality has increased by 85% among people aged over 65 over the last 20 years. And the heat also leads to a drop in productivity among workers, obviously, and particularly among agricultural workers. In 2022, this cost the global economy $863 billion.
An impact on communicable diseases
The potential for transmission of dengue fever, for example, has increased by around 28% since the 1950s. There is also an issue in the geographic distribution of diseases: the mosquito carrying malaria, for example, is now present in regions that were inaccessible to it before, because it was too cold… And climate change also has a big impact on certain less serious conditions, and in particular on the multiplication of allergens.
On the pollution side, however, the news is good: since 2005, mortality caused by air pollution has fallen by 18%, and this is largely due to the drop in coal consumption. In 2020, air pollution due to the combustion of fossil fuels still caused nearly two million deaths worldwide, as many deaths as we could avoid by phasing out fossil fuels.
We are far from it: almost 85% of the primary energy produced every day in the world still comes from fossil fuels. This will be one of the big topics of discussion at COP28, we will come back to it. But what is interesting in the report of the Lancet, is that it shows that many actions which make it possible to fight against climate change also bring concrete benefits for our health: this is the case for atmospheric pollution, but also for food or mobility, for example. example. These are what we call co-benefits, that is to say the benefits that we will obtain from action against climate change, but in other areas.
For example, better insulating your home helps reduce your carbon footprint, but also reduces your energy bill. And this is very important, because climate change does not allow us to immediately experience the results of our actions: there is no correlation between the greenhouse gas emissions that are produced in one place to another. given time, and the impacts of climate change at that place and time. There is a very strong gap in space and time, which obviously creates great injustice. And the problem we have is that to act, we often need to see the concrete results of our actions. And with this gap in time and space, this is not possible. Hence the interest in co-benefits.
We act if we have an interest in doing so
We are fundamentally guided by our interests. And as is often the case, our health is one of our main concerns, so we have an absolutely wonderful lever for action to pull. And we would do well to emphasize the benefits of climate action for our health much more.
When we talk to people about climate change, we constantly tell them about the disasters that will occur if they don’t act. It is often heavy-handed and moralizing. But on the other hand we never talk to them about the benefits they could get if they took action. In my opinion, this is a fundamental error.