As winter approaches, understanding the impact of weather conditions our bodies is crucial. "Perceived temperature" highlights how we experience cold by considering both actual temperature and factors like wind chill.
Despite lacking scientific precision, this estimation method significantly contributes to increasing awareness about the risks associated with extreme weather.
In winter, the temperature felt in the wind drops sharply compared to a sheltered area. This is due to thermal convection, which also applies to an ordinary fan. The weather reports calculate the temperatures in the shelter when wind and sun are absent. On the other hand, an accurately measured temperature of -5°C corresponds to a perceived temperature of -10°C with a 20 km/h wind and up to -16°C with a 60 km/h wind. Heat transfer via convection causes the increased feeling of cold, known as "wind chill."
Heat exchange occurs between the surface of the skin and the thin layer of air in contact with this surface when you are outside in cold weather. Your skin will heat up the air around it because it is roughly 35°C. Since heat transfer is proportional to the temperature differential between the two bodies, it becomes progressively weaker as the air around the skin heats up.
In the presence of wind, the perceived temperature drops several degrees.
However, in the presence of wind, the air flows swiftly, replacing the warm air from the skin with cold air. As a result, the skin emits the greatest amount of heat permanently, with the temperature differential being significant.
A fan works on the same principle, constantly moving the mass of air so that "fresh" cold air comes into contact with the skin.
Weather forecasts are progressively using the concept of "perceived temperature," which considers the wind. However, this estimation is not scientific. It serves as a warning in harsh climate regions for people to take precautionary measures against cold-related damage such as frostbite and hypothermia. Wearing insulated clothes or multiple layers of clothing that trap warm air and hold heat can help reduce the wind chill factor.