Heat records have been broken in several places in Germany in the recent past. Climate researchers almost agree that climate change is to blame. While the air temperature in Germany rose by 1.6 degrees between 1881 and 2021, the number of hot days also increased in almost all regions of Germany. According to the German Weather Service (DWD), there were now an average of six such days with over 30 degrees Celsius per year in Cologne in 1961 and 1990, and between 1991 and 2020 there were already twelve days on average. The four warmest years since 1881 were 2014, 2018, 2019 and 2020 anyway.
And just as climate researchers are observing the connection between climate change and hot days, economists are studying how rising temperatures are affecting productivity. Because the greater the damage, the more it makes economic sense to invest in measures to combat climate change.
In short, the result is: The damage is high. Stanford University's Marshall Burke and Vincent Tanutama calculated that higher temperatures between 2000 and 2015 (compared to average temperatures from 1951 to 2000) caused $4 trillion in lost productivity in the US and Europe. For comparison: Economic output in the entire EU in 2015 was around 13.5 trillion dollars.
The reasons are numerous: economists Tamma Carleton and Solomon Hsiang from the University of California, Berkeley found out that productivity falls when temperatures are high, mainly because of lower crop yields, lower worker productivity and poorer health.
A temperature rise of just a few days is about enough to damage crops. At the moment you only have to look at Italy, where the heat wave has already hit. The Coldiretti farmers' association there warns of crop failures of up to 70 percent in some areas.
Of course, workers who do manual labor have more trouble working in hot weather, but office workers also find it harder to concentrate and less productive in hot weather.
However, Carleton and Hsiang also show that there are indirect effects of higher and higher temperatures on productivity. So more energy is needed. And to escape the heat, many people choose to move. Also not to be neglected is that the heat also makes people more aggressive, leading to more (unproductive) conflicts.
Productivity losses are greatest in countries that are already very warm. Unfortunately, these are also often more severely affected by climate change. But hotter weather in temperate regions like Germany also entails losses in productivity.
Stanford scientists Burke and Tanutama compared annual mean temperatures to local productivity. Their result: Productivity peaks at an annual average temperature of ten degrees Celsius. Only very few places in the world, especially in Scandinavia, Russia and Canada, have average temperatures lower than ten degrees. So they're the only ones who could benefit from higher temperatures. According to the study, productivity in the rest of the world is doomed to suffer from rising temperatures. Because above ten degrees, the growth of the gross domestic product drops sharply with rising temperatures, in poor as well as in rich countries.
That seems counterintuitive. After all, many poor countries are dependent on climate-sensitive sectors such as agriculture and cannot afford climate protection measures. Anyone who thinks that wealthier countries can use air conditioning to offset the impact of higher temperatures on their large service sectors is wrong. Lee Kuan Yew, Singapore's first prime minister, once said, "Without them, many of our humble workers would probably be sitting under coconut trees to escape the heat and humidity, rather than working in high-tech factories."
Many reasons why richer countries are not better able to adapt to higher temperatures than poorer countries are still unknown. But the power of air conditioning to cool the mind seems limited. Anthony Heyes of the University of Ottawa studied the effects of outside temperatures on American judges' decisions in more than 200,000 immigration cases. With rising outside temperatures, the chances of a residence permit fell, all other things being equal, even if the judges decided in air-conditioned courtrooms. So outside temperatures could affect how highly skilled professionals do their job, even when working indoors.
Other studies have shown that even in wealthy countries like the US, where technology can iron out much of the heat damage, farmers suffer from lower crop yields due to warmer climates, while construction and manufacturing sectors suffer from lower labor productivity.
Even if some people in this country are certainly happy about the additional warm days, it is quite certain that they are bad for productivity.
