Characteristics and causes of daily and annual changes of temperature

The daily variation of temperature is generally small, and the annual temperature difference is generally large. Because the temperature difference between winter and summer is generally very large, and the daily temperature difference is generally a comparison of the temperature difference between noon and night (except for some areas, such as Gobi, where the daily temperature difference is very large). The annual temperature difference depends on the latitude of the region, and generally the annual temperature difference is relatively large in the mid-latitude region.

Daily changes, the highest temperature is around 2 pm, and the lowest temperature is around sunrise. The annual change shows that it is the hottest in July, the coldest in June, the hottest in August and the coldest in February in the northern hemisphere in 65438+ 10. The southern hemisphere is opposite to the northern hemisphere.

The temperature decreases from low latitude to high latitude, so the isotherm is generally parallel to latitude. The temperature of the sea and land at the same latitude is different. In summer, the isotherm protrudes in the direction of high latitude on land and in the direction of low latitude on the ocean.

Extended data

According to the different calculation time, there can be the average temperature of a certain day, month and year. Usually, the daily temperature is expressed by the average temperature.

Due to different weather stations, the number of observations per day is also different. According to the regulations of China's meteorological department, the daily average temperature is to average the temperatures measured four times every day at 02: 00, 08: 00, 14: 00 and 20: 00, and the accuracy should be110 degrees.

In addition to the daily average temperature, there are also waiting (5 days), ten-day (10 days), monthly and annual average temperatures. Express the changing characteristics of temperature in different periods. Meteorological department every day at 02: 00, 08: 00, 14: 00, 20: 00 (Beijing time).

Observe the temperatures at 02: 05: 08: 00, 1 1: 00, 14: 00, 17: 00, 20: 00 and 23: 00 every 6 hours or every 3 hours. For special needs (such as aviation), meteorological observations are even made at intervals of 1 hour and half an hour.

① Average temperature on a certain day: the average of the highest and lowest temperatures on a certain day.

② Monthly average temperature: the average of the average temperature for many days in a month.

(3) Average temperature in a certain year: the average of daily average temperature (or monthly average temperature) in a certain year.

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