Meishan climate factors?

Climatic characteristics of Meishan city

There are many mountains and hills in Meishan city, with high terrain in the west and low terrain in the east, with the highest elevation of 3522 meters and the lowest elevation of 335 meters. Natural conditions are complicated. The sea-land monsoon changes alternately every year, controlled by the subtropical high in the western Pacific in summer, influenced by the cold air in northwest Asia and Mongolia in winter, and the annual variation of solar radiation forms many climate types in this area.

1. The humid climate in the middle subtropical zone in Pingba hilly area is obvious.

Mild climate, abundant rainfall, four distinct seasons, rain in the same season; There is no cold in winter and no heat in summer; Long frost-free period, less frost and snow; Less sunshine; The time distribution of light, heat and water is synchronous with the growth and development period of crops, with good climate suitability, long growth period, large planting degree and rich yield.

1. Due to the influence of topography and landforms, the annual average temperature tends to be higher in the east and lower in the west. The average temperature in Renshou County is 17.4℃, which is the highest in the city, while that in Dan Ling is 16.6℃, which is the lowest in the city. The hottest months are July and August, and the average temperature is 25.4-26.3℃, which is extreme.

2. Abundant rainfall and uneven distribution in time and space. Rainfall increases from northeast to southwest according to different regions. The average annual rainfall is 983- 1490 mm, the minimum annual rainfall in Pengshan is 983MM, and the maximum annual rainfall in Hongya is 1490 mm. The rainfall is concentrated from May to September, accounting for about 85% of the total annual rainfall (the maximum daily rainfall is 1490 mm).

3. Sunshine Sunshine hours are 1060- 1202 hours, which is 24-28% of sunshine hours, which is less than that in the same latitude area, and it is one of the low sunshine areas in China.

Second, the three-dimensional climate in the southwest mountainous area is obvious.

With the increase of altitude, a complete climate zone spectrum from sub-potential zone-warm temperate zone-cold temperate zone-sub-cold zone appeared in the southwest mountainous area. The vertical difference of climate (stereoscopic climate) is obvious. The temperature decreases with the elevation, and the temperature decreases by 0.66℃ for every elevation of 100 meters. Rainfall increases with altitude; It has the climate concept of higher altitude, lower temperature and more rainfall.

Third, there are many kinds of meteorological disasters with high frequency.

1, due to the influence of monsoon, topography and landform, the drought occurred frequently in Renshou County, Dongpo District and pengshan county, causing great harm. According to statistics, the frequency of spring drought is 54.3-75%, summer drought is 76.2- 100%, and summer drought is 65438+. The winter drought frequency is 22.9-365,438+0.8%. Drought not only reduces food, makes drinking water difficult for people and animals, but also affects social stability. From1July 1997 to1April 1998, five droughts occurred in Renshou County, which lasted for nearly 200 years: summer drought, autumn drought, winter drought, spring drought and summer drought.

2. Rainstorms and floods are mainly caused by local rainstorms and transit floods. During the flood season (May-September), there are 3-5 heavy rains in all districts (counties) of the city, with concentrated rainfall time and high intensity, which easily causes heavy losses. According to statistics, the annual average frequency of flood is 76.5%- 173.5%.

3. Wind and hail disasters mostly occur in the process of strong convective weather in spring and summer. Thunderstorms, strong winds and hail often occur at the same time, which not only causes devastating blows to crops, but also causes great losses to people's lives and property. 1At 8: 50 p.m. on April 28th, 1997, 9 towns and villages in 5 districts of Renshou County were hit by strong winds and hailstones, with the maximum diameter of 9CM and the grain loss of 265,430 grains. Houses were damaged 1.58 rooms, 3 people died, 3 people were seriously injured, large livestock died 1.002 heads, water conservancy, power supply and communication facilities were seriously damaged, and the direct economic loss was 1.02 million yuan. In addition, the low temperature in spring, continuous drizzle in autumn, landslides, pests and diseases and forest fires caused by meteorological factors have also affected the city to varying degrees.