Air humidity in Chengdu

The average annual relative humidity in Chengdu is 69-84%, in which the relative humidity is generally below 80% in April-May and above 80% in other months.

Due to the geographical location of Chengdu, the climate in Chengdu has a remarkable feature: the air is humid, so although the temperature is not high in summer (the highest temperature generally does not exceed 35℃), it looks sultry; The average temperature in winter is above 5℃, but it is very cold because of cloudy days and humid air.

1. What are the climatic characteristics of Chengdu?

Chengdu belongs to subtropical humid monsoon climate zone. Due to the influence of geographical conditions such as geographical location, topography and underlying surface, it has obvious vertical climate and complex local microclimate. The plain hilly area belongs to the humid and semi-humid climate zone in the middle subtropical zone of Sichuan Basin, with mild climate, four distinct seasons, long frost-free period, abundant rain and little sunshine. The mountainous area belongs to the "basin-surrounding mountainous area" with a cool and humid climate. The middle and low mountains above 1300 meters above sea level have a cool climate, from short summer to long winter without summer, with insufficient heat, more rain, frequent fog and mist, and little sunshine all year round. The mountainous area above 3000 meters above sea level has a cold climate, a long frost-free period and plenty of sunshine, which is extremely cold, resulting in "low temperature in spring and short summer"?

Two. Climate factors (1990-2005)?

1, Chengdu temperature?

(1) Annual and monthly average temperature?

The average temperature in the city is 15.6 ~ 16.9℃, 6.2 ~ 7.7℃ in winter,13.6 ~15.1℃ in spring, 23.2~24.6℃ in summer and 65433℃ in autumn. The hottest month appears in July, with an average monthly temperature of 25.0 ~ 26.3℃, and the most Leng Yue appears in 65438+ 10, with an average monthly temperature of 5.0 ~ 6.2℃. ?

(2) Extreme temperature in Chengdu?

The extreme maximum temperature in the city is 35.5 ~ 37.7℃, which usually appears in July. The extreme minimum temperature in the whole city is -5. 1 ~-3.6℃, most districts and counties appear in 65438+February, and a few appear in 65438+1October. ?

(3) The first sunrise after 10℃ is in the middle of March, and it appears at the end of 1 1 all day. ?

2. What is the sunshine time in Chengdu?

The average annual sunshine hours are 825.7 ~ 1202.9 hours, with Jintang having the most sunshine hours and Dujiangyan having the least. In the whole year, 65438+1October, February and 65438+February are the least, and the monthly sunshine hours are 3 1.5 ~ 56.4 hours, and the sunshine hours are the most in July and August, which are 109.5 ~ 153.9 hours. ?

3. Is it cloudy or sunny?

The number of sunny days in the city (80% of the daily average total cloud cover) is 18 ~ 23 days.

Third, the climate characteristics of the four seasons in Chengdu:

1. Spring: The temperature rises early, which is beneficial to the growth of trees and crops in spring, but it is unstable when it rises and falls suddenly, and it is prone to continuous low temperature, which affects the timely sowing of crops in Da Chun.

2. Early summer: the temperature is moderate and the daily temperature difference is large.

3, midsummer: summer is hot and rainy, and the light is strong.

4. Autumn: there is a short period of cool and rainy weather in autumn, and a long period of crisp weather in autumn.

5. Winter: There is no severe cold in winter, which is beneficial to the growth of Koharu and animal husbandry. The continuous foggy weather has a great influence on transportation and shipping, especially in winter when it is dry and less sunshine.

Humidity in meteorology generally refers to air humidity, which is the physical content of water vapor in the air. Liquid or solid water in the air is not considered as humidity. Air without water vapor is called dry air. Because the water vapor in the atmosphere can account for 0% ~ 4% of the air volume, when listing the components of various gases in the air, it generally refers to the composition of these components in dry air. At a certain temperature, the less water vapor in a certain volume of air, the drier the air; The more water vapor, the wetter the air. The degree of dryness and wetness of air is called "humidity".

The mass of water vapor contained in air per unit volume is called absolute humidity. The absolute humidity of air does not determine the speed of water vapor on the ground and people's feeling of humidity. People call the absolute humidity of air at a certain temperature and the percentage of saturated air pressure at the same temperature as relative humidity. The comfortable humidity of human body is: the relative humidity is lower than 70%.

Chengdu hygrometer 2019.10.11