What's the climate like in Nanjian County, Dali Prefecture, Yunnan Province?

The monsoon climate zone of subtropical plateau in Nanjian Yi Autonomous County

1. Monsoon climate in low latitude mountainous areas

Nanjian is adjacent to the East Asian continent in the north and the tropical ocean in the south. It is located in the tropical land-sea monsoon area in western China. The climate has obvious seasonal changes with the advance and retreat of the land-sea monsoon, thus forming a low-latitude mountain monsoon climate with distinct dry and wet seasons, inconspicuous four seasons and the same season of rain and heat. The dry season (165438+ 10 to April of the following year, also known as winter half year) is mainly controlled by the dry and warm air flow of the west wind in the southern branch of the mainland, which makes the weather clear in winter and spring and partly cloudy. High temperature, low humidity, high wind speed and large evaporation form a dry and warm climate with perennial drought in winter and spring. The wet season (May ~ 10, also called summer half year) is mainly controlled by the southwest warm and wet monsoon from the west side of the Pacific high and the east side of the Indian low, during which there are more clouds and less sunshine. High humidity and low wind speed; Rainy days and heavy precipitation; There is a lot of evaporation and evaporation consumes a lot of heat, which forms the characteristics of the same season of rain and heat in summer and half a year.

Second, vertical climate.

Nanjian county is characterized by mountains, numerous peaks and deep valleys. The relative height difference between Taiji Peak, the highest point in the north of the county, and Lancang River, the lowest point in the south, is 2067 meters. With the increase of topography, the atmospheric transparency increases and the surface wave scattering is stronger; At the same time, the dynamic uplift conditions are also enhanced, which leads to the decrease of temperature and the increase of precipitation with the increase of altitude. Therefore, under the same atmospheric circulation situation, the vertical climate transition state of south subtropical zone, middle subtropical zone, north subtropical zone, south temperate zone, middle temperate zone and north temperate zone appears in turn from the valley along the river to the highest peak of the county. There are vertical distribution of dry and wet climate types such as drought, semi-humid and humid.

Third, regional climate.

Because the main vein of Ailao Mountain inclines from the northwest to the southeast of Nanjian County, the whole county is divided into obviously rainy areas and less rainy areas under the barrier of warm and humid airflow in the northwest and southwest of Ailao Mountain, with more rain in the southwest and southeast and less rain in the northeast. Due to the influence of Wuliang Mountain on the west side of Ailao Mountain, the climate on the west side of Ailao Mountain is bounded by Wuliang Mountain, forming two regions with prominent hot and humid conditions. Thus, three local climates with different hydrothermal conditions are formed in the southwest, southeast and north of the central part of the county. It shows that there are obvious horizontal differences in dry, wet, cold and warm in different areas at the same altitude.

Four, sunshine, temperature

1, photos of Japan

From 1978 to 2005, the meteorological observation data of Nanjian Meteorological Observatory recorded that the average annual sunshine hours in 28 years were 2,458.8 hours, the highest annual sunshine hours were 1986, which was 2,663.2 hours, and the sunshine percentage in that year was 60%. In 2004, the sunshine hours were the least, 2257.5 hours, and the sunshine percentage was 5 1%. The highest monthly average sunshine hours over the years is in March, reaching 252.5 hours; The lowest monthly average sunshine hours is in July, which is 137.2 hours.

2. Temperature

From 1978 to 2005, the average annual temperature for 28 years was 19.3℃. The highest annual average temperature 1988 is 20.2℃; The lowest values are 1992, 1997 and 2000, that is, 18.7℃. The annual extreme maximum temperature is 36. 1℃, which appeared on May 29th, 2005. The extreme minimum temperature of the whole year is -0.8℃, which appears on1982 65438+February 27th. The highest monthly average temperature is 24.3℃ in June. The monthly average minimum temperature is 1 month and 12.5℃.

Verb (abbreviation for verb) precipitates and evaporates

1, water drop

1978 to 2005, the observation data of Nanjian county meteorological station recorded the average annual precipitation of 755.5mm； in 28 years; The year with the most precipitation is 200 1 year, and the precipitation is1.061.5mm. The years with annual average precipitation exceeding 1 000 mm include 1986 and the precipitation is1024./kl. The precipitation is only 460.5 mm. The month with the largest annual average precipitation is August, and the average precipitation over the years is138.2 mm; The month with the least precipitation is 65438+February, and the average precipitation over the years is12.7 mm. ..

The average start date of the rainy season is June 3rd, the average end date is 65438+ 10/7, and the average rainfall of the rainy season is 599.5mm. The rainy season started as early as May of 10 and appeared in 200 1 year and 2002. On July 24th at the latest, it appeared in 1988. The rainy season ended as early as September 18 and appeared in1994; The latest date is165438+1October 2 1, appearing in 1995. The maximum rainfall in rainy season is 1 0 18.2mm, which occurs at 200 1. The minimum rainfall in rainy season is 258.8 mm, which appears in 1988.

The maximum precipitation over the years at Nanjian Meteorological Station occurred on July 13, 2005, with a precipitation of 99.0mm；; On June 20th, there was 1990, reaching 90 mm or more, which was 96.7 mm, and the daily precipitation in 28 years was ≥0. 1 mm, which was 343 1 day, with an average of 1.23 days per year. The number of precipitation days ≥ 10 mm * * is 685 days, with an average of 24 days per year; The number of days of precipitation ≥ 25mm * * is 172 days, with an average of 6 days per year; There are 19 days with precipitation days ≥50 mm * *, which is close to the average value of 1 day with annual precipitation exceeding 50 mm.

Step 2 steam your hair

From 1978 to 2005, the 28-year average annual evaporation recorded by Nanjian Meteorological Station was 3 044.8 mm, and the maximum annual evaporation was 1984, reaching 3 590.9 mm; The minimum evaporation appeared in 2002, which was 2531.9mm. The maximum monthly evaporation was in May, reaching 382.4mm.: The minimum is 1 1 month, which is171.0mm. ..

Weather phenomenon of intransitive verbs

From 1978 to 2005, according to the data of Nanjian Meteorological Station, there were 4805 rainy days in 28 years, with an average of 172 days a year. Snowfall lasted for 4 days, which occurred in 1983, 1986 and 2000 respectively. The number of exposed days is 6053 days, with an average of 2 16 days per year; The number of frost days is 758 days, with an average of 27 days a year; Thunderstorm days are 1 187 days, with an annual average of 42 days, of which lightning days are 55 1 day (excluding 1978 ~ 1979); Hail days have 20 days; Fog days are 25 days and light fog days are 80 days. Haze appeared 16 days, of which 1999 appeared for 7 days; The freezing days lasted for 3 days, all of which occurred in1999; 1984 has a tornado; The number of windy days (≥ 17.0m/s) is 937 days, with an average of 33 days per year; Strong winds occur for 36 days, with an average of one day a year.