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|THURSDAY, JUNE 8 - LAG OF THE MAXIMUM TEMPERATURE
You may have heard that sunburning happens fastest during the midday
hours. That is, the hours around noon. That's when the sun is highest
in the sky, so its rays are most direct and thus most intense.
But have you noticed that the highest temperature of the day usually doesn't occur
until later in the afternoon. In fact, the high temperature today probably occurred
sometime after 3pm.
So why doesn't the day's highest temperature coincide with the most intense sunlight?
The answer has to do with the way air heats up. The sun doesn't really heat the air
directly - instead, the sun heats the ground, and the ground heats the air.
Just like cold pizza takes time to heat up in the oven, the ground takes time to
heat up from sunshine. And then it takes time for the ground to heat the air.
This step-by-step heating creates a delay of a few hours between the time of the
most intense sunlight and the time of the day's highest temperature.