Most people think that the heat of the day is at its peak between 1 and 2 pm, when the sun is at its highest. The confusion probably comes from the rules of caution regarding the sun’s rays, and in the first place, the avoidance of prolonged exposure between 11am and 4pm. However, in summer, the heat peaks between 4pm and 6pm. If the sun is at its highest between 1pm and 2pm, why is this not the hottest time of the day? Let’s try to find out!
The air is not warmed by the sun
Let’s put an end to this idea right away: the sun does not heat the air. This is not true! To absorb the energy of our star’s radiation and to warm up, we need a non-transparent “body”, thus excluding glass, water and air. Between 1pm and 4pm, when the sun’s radiation is at its peak, the ground, the walls of buildings or objects store this heat and then release some of it back into the atmosphere in the form of infrared radiation
Greenhouse gases, the cause of all our problems
Greenhousegases, the gaseous components in the atmosphere responsible for global warming, trap infrared radiation emitted by the ground and thus contribute to the “greenhouse effect” by increasing atmospheric temperatures. This process takes time, so that the heat peak only occurs between 16h and 18h
Source
- sciencing.com (What Is the Hottest Time of the Day? – EN)
- globe.gov (How the Temperature Varies During the Day and Night – EN)
- quora.com (Why is it hotter during the afternoon (2-3 PM) than it is at noon – EN)
- donneespubliques.meteofrance.fr (FR)
