The “Failure” to Ban Fossil Fuel Projects in the Developing World at COP27 May Actually Save Lives.

The narrative coming out of COP27 is that the major ‘victory’ was an establishment of a ‘loss and damages’ fund where high-income countries pay reparations to low-income countries for the detrimental impacts of their emissions. This supposed positive outcome is being contrasted with what is being deemed as a major ‘failure’: the lack of a clear commitment to ban international development financing of fossil fuel projects in the developing world.

The scope of things that can be lost or damaged from climate change is broad, but here we will look at the specific case of the loss of life from changes in temperature. In this case, a close look at the best available science does not support the above victory/failure narrative, in fact, it flips it on its head.

When it comes to the impact of extreme temperatures, the intuition is that rich developed countries—who are responsible for the vast majority of historical emissions—tend to be in cooler climates and poor developing countries tend to be in hot climate climates. Thus, emissions of greenhouse gasses disproportionality come from developed countries and disproportionately impact developing counties, making the extreme heat they already experience that much more deadly.

However, a closer look at the data reveals a much more complicated story—one that undermines this simple intuition. As it turns out, cold temperatures are associated with roughly ten times more deaths than hot temperatures, and this is even true of countries currently residing in hot climates. The key reason why deaths related to cold weather can outnumber deaths related to hot weather so universally is that societies are highly adaptable to the climates that they experience. This acclimation means that what might be considered a hot or cold day is relative and varies a great deal from place to place.

This variation is typically measured by what’s called a location’s “minimum mortality temperature,” which is the daily average outdoor temperature that minimizes the population’s overall death rate. When temperatures go above or below the minimum mortality temperature, researchers can see an increase in death rates in the statistics.

One might think that the minimum mortality temperature would be roughly constant from place to place, maybe around 72°F (22°C). If this was the case, then cold countries (who spend most of their time below 72°F) might see decreased deaths from climate warming, and hot countries (who spend most of their time above 72°F) might see increased deaths.

But the data tells a different story. The minimum mortality temperature is not constant. Instead, it varies in a predictable way: hotter locations have hotter minimum mortality temperatures than colder locations. Furthermore, the minimum mortality temperature spans a substantial range. For example, Amsterdam has a minimum mortality temperature of 63°F (17°C), while San Juan, Puerto Rico, has a minimum mortality temperature of 86°F (30°C).

Higher minimum mortality temperatures in hot countries mean that even in those locations, cold-related deaths tend to outnumber heat-related deaths by a substantial margin. For example, there are approximately five cold-related deaths for every one heat-related death in Latin America and the Caribbean, there are eight cold-related deaths for every one heat-related death in Southern and South-eastern Asia, and there are a whopping 58 cold-related deaths for every one heat-related death in Sub-Saharan Africa.

Estimates of annual average cold-related and heat-related deaths from 2000 to 2019 in different regions of the world. Adapted From Zhao et al. (2021).

Given the disproportionate burden that cold temperatures place on human health, it is perhaps not surprising that since 2000, warming has caused a larger decline in cold-related deaths than an increase in heat-related deaths globally, and even in hot low-income countries. This makes it difficult to justify reparations for heat deaths, throwing into question how much of a “victory” the ‘loss and damage’ fund may ultimately turn out to be.

Turning to the ‘failure’ to rapidly phase out fossil fuels, including all new natural gas projects in low-income countries, the data on temperature-related deaths tells another critically relevant story. Even heat deaths themselves have been decreasing in most locations over time as it has warmed. Further, looking across societies today, high-income countries are much less sensitive to non-optimal temperatures than low-income countries.

These two facts tell us that economic development—and its association with better infrastructure, energy access, healthcare systems, air conditioning adoption, etc.—drastically reduces societies’ sensitivity to all weather and climate extremes, including extreme temperatures. And that reduction in sensitivity has predominated over the detrimental impacts of increasing temperatures. Thus, if the goal is to reduce the impact of non-optimal temperatures on people, the most direct and demonstrably effective way is to facilitate economic development.

Unfortunately, the simple truth is that for low-income countries, economic development necessitates more, not less, greenhouse gas emissions in the near term. This is because this development entails increases in infrastructure made from steel and concrete, which cannot currently be produced cost-effectively without greenhouse gas emissions. It’s also because this development requires vastly increased energy use both in industry and in the daily lives of people. There is little real-world evidence that developing economies can be powered by wind and solar electricity, and natural gas and oil remain the most cost-effective and preferred way to quickly expand industrial output, access to electricity, and access to transportation in those places where they are most lacking.

Thus the reported “failure” to inhibit the energy projects that will facilitate economic development in low-income countries may ultimately be a success so long as the measure of success is decreasing the impacts of warming on people.

Article Image Credit: "UNFCCC_COP27_18Nov22_UNSG_G77China_KiaraWorth-4" by UN Climate is licensed under CC BY-NC-SA 2.0