The geographical environment of Xintian County

Xintian County has complex terrain, intertwined mountains, and complex climate characteristics. Xintian County is located in the mid-subtropical continental monsoon humid climate zone, with high temperatures, short severe cold periods, short hot summer periods, changeable spring temperatures, frequent cold waves, rainy summers, frequent droughts in summer and autumn, sufficient sunlight, long frost-free periods, and four distinct seasons. .

The annual average temperature in most places in Xintian County is 17.6-18.5℃, the daily minimum temperature is only below 0℃ for 8-15 days, and the frost-free period is 286-311 days. The annual average number of snowfall days is 4 to 7 days, and the extreme minimum temperature is -4.9 to -8.4°C. The accumulated temperature with daily average temperature ≥10℃ reaches 6450~6800℃. The average annual sunshine hours are 1384 to 1688 hours, the total solar radiation is 101.5 to 133 kcal square centimeters, and the annual average precipitation is 1280 to 1530mm. The average annual sunshine hours in the county range from 1384.1 to 1688.0 hours. It has the most sunshine in summer and autumn, and the least in winter and spring. July and August are the months with the most sunshine, usually more than 200 hours. February has very little sunshine, between 53.7 and 58.9 hours.

The annual average in Xintian County Precipitation ranges from 1279.6 to 1527.2mm, with more geographical distribution in the south than in the north, and more in mountainous areas than in plains. Precipitation in a year is mainly concentrated in the spring and summer rainy seasons, accounting for about 70% of the total annual rainfall, and the autumn and winter rainy seasons account for about 30%. In some areas, spring is more abundant than summer, and autumn is more abundant than winter. The month with the heaviest precipitation is April or June, and at least January or February. Precipitation occurs at the turn of spring and summer, especially April to June, which accounts for the most precipitation in the whole year. 40% of the total. The rainy season in the county generally starts in mid-to-late March and ends at the end of June. Floods and droughts

During the flood season between spring and summer in Xintian County, heavy rains are concentrated and rainfall intensity is high. In addition, there are mountains and hills, and steep slopes cause rapid runoff, which can easily cause flash floods and have a great impact on industrial and agricultural production. Data from 1951 onwards show that the proportion of flood disasters gradually decreased from the 1950s to the 1980s. After the 1980s, the county suffered serious flood losses in four years: 1981, 1985, 1991, and 1994.

In summer and autumn, due to the long-term control of the subtropical high, it is easy to form high-temperature and drought weather. Data from 1951 onwards show that there were 23 years of drought in Xintian County, among which the most severe ones were There are five dry years including 1960, 1989, 1990 and 1991. Countywide, droughts occur more frequently than floods.

Cold wave and low temperature

The low temperature weather of the cold wave that has a severe impact on agriculture is mainly composed of three colds (late spring cold, low temperature in May, and cold dew wind). The late spring cold occurs around March. Lasting from late to early April, it constituted an agro-meteorological disaster for early rice sowing and seedling cultivation. When low temperature weather occurs in May, it will affect the greening of early rice. The occurrence of cold dew and wind will affect the heading and flowering of late rice. Xintian County has freezes in 50 to 60% of the years.

Wind and hail weather

Xintian County has strong winds throughout the year, most in spring and summer, accounting for 80% of the number of windy days throughout the year. The annual average number of hailstorms occurring from February to April or June to July is about 0.2 to 0.8 days.