Hot Topics: Comparison and Interaction of Heatwave-related Societal Responses and Public Health Impacts
Extreme heat is one of the most significant public health threats posed by climate change. It causes an estimated 489,000 deaths annually worldwide, a third of which in Europe. Despite improved heat risk reduction strategies, important gaps remain in how we understand and represent the relationship between heatwaves and societal responses.
With this research, I show that not only the intensity of heat is important, but also the duration. In Germany, health problems and social unrest were found to be more strongly associated with warmer periods that lasted for weeks to months than with short periods of extreme heat. Prolonged heat therefore seems to be a greater burden on people and society than a few exceptionally hot days.
In addition, the amount of moisture in the environment plays an important role. Both very dry and very humid conditions can increase the health risks of heat and affect the number of deaths.
Online search behavior
The study also looked at online search behavior. During heat periods, people were more likely to look for information about heat symptoms and ways to deal with them. Remarkably, this increase in searches coincided with periods in which mortality increased. Online search behaviour can therefore be a useful indicator to see how badly a heat wave affects the population.
Finally, it appears that earlier exposure to a heat wave may better prepare people for the next warm period, especially vulnerable groups. The key message is that effective heat protection should not only take into account temperature, but also the duration of heat, humidity, and how people seek information and react to extreme weather events.
More information on the thesis.