Traditional Culture Encyclopedia - Weather inquiry - Day and night temperature range

Day and night temperature range

Diurnal temperature range is the most studied and most important concept in daily temperature range. The daily temperature range refers to the difference between the highest temperature and the lowest temperature for 24 consecutive hours.

The factors affecting the daily temperature range are latitude, season, underlying surface, topography, weather and so on.

Latitude: the daily temperature difference decreases with the increase of latitude, because the solar altitude angle decreases with the increase of latitude in a day. The area with the largest daily temperature difference in the subtropical region. The average daily range in tropical area is about 65438 02℃, in temperate area it is 8 ~ 9℃, and near the polar circle it is 3 ~ 4℃.

Season: Generally, the daily range in summer is greater than that in winter, but the maximum value is not in summer solstice. This is the reason why the sun's altitude angle is high at noon from summer solstice, but the night duration is short, the ground radiation cooling is insufficient and the minimum temperature is not low enough. The maximum daily range in mid-latitude area appears in early summer and the minimum in winter.

Underlying surface: the difference of thermal conditions between land and sea surface leads to the difference of daily temperature difference, and the daily temperature difference of ocean is smaller than that of land.

Terrain: The temperature difference between day and night in concave terrain is greater than that in convex terrain. Generally speaking, the daily temperature difference in low concave areas (such as basins and valleys) is greater than that in flat areas, and the daily temperature difference in flat areas is greater than that in convex areas (such as hills).

Weather: The temperature difference on cloudy days is smaller than that on sunny days, and it is even smaller on windy days.

Terrain: The closer to the ground, the greater the daily temperature difference due to the large long-wave radiation on the ground.