Daily fluctuations of temperature

The surface of the ground on steep before dawn, having in the absence of clouds, the possibility of loss of heat in the black sky in the night. Accordingly, usually, believe that the low temperature, as it takes about an hour before sunrise. As soon as the sun comes up, its radiation begins to warm the surface of the earth as the earth's temperature rises heat convected from the surface layers of air directly above it. There is thus a gradual increase in air temperature and the sun continues to grow, and also some time after it has passed the Zenith, due to the fact that some of the heat received by the earth from the sun and stored in its upper layers of the entire morning runs up and lost by convection in the early afternoon. Therefore, usually, to find high air temperatures between 14.00 and 16.00 h (sun-time). In fact, between 13.00 and 17.00 hours cannot be expected to very large changes in temperature.

Average basis, it is logical to assume that there is some rough sinusoidal relations between the sun time and air dry bulb. The curve is not fully balanced, since the time between high and low temperatures is not necessarily equal to that between the highest and the lowest.

For the month of June, sunrise about 04.00 hours and sunset at about 20.00 o'clock Time, the minimum temperature is about 03.00 hours and time the highest temperature 15.00 o'clock There is, thus, within 12 hours at temperature increase. Since that night, for an unlimited period of cooling is only about 7 hours (20.00-03.00 h) curve is wider in the daytime than at night. The opposite would be the case in December..