Introduction to the climate of Heihe, Mohe and Manzhou.

Heihe City is located in the middle and high latitudes, at the northern end of temperate zone in China climate division, and belongs to continental monsoon climate. In winter, affected by Mongolian high pressure, it is cold and dry; Summer is controlled by the southeast monsoon, which is warm and rainy. It is characterized by long winter and short summer, low temperature and cold humidity.

1. The main characteristics of agricultural climate include: abundant sunshine, the same season of rain and heat, large temperature difference between day and night, and low temperature in winter. Rich in light energy resources, the annual average total radiation is 105- 1 10 kcal/cm2; During the crop growing period from May to August, the total solar radiation reached 67 kcal/cm2, accounting for about 60% of the whole year. The total sunshine hours from May to September can reach 1400- 1500 hours, and the average sunshine hours in the growing season are about 8 hours, of which the average sunshine hours in June are about 9 hours, which can fully meet the needs of crop growth and development. The active accumulated temperature of ≥ 10℃ in our city is between 1500-2450℃, and the precipitation here (May-August) can reach 350-400 mm, accounting for about 80% of the annual precipitation, mainly concentrated in the crop growing season, which improves the effectiveness of heat resources. The daily average temperature ranges from 10-20℃, which is about twice as high as that in the Yangtze River basin. High daytime temperature is beneficial to crop photosynthesis and organic matter accumulation; The low temperature at night can inhibit the respiration of crops, thus reducing the consumption of nutrients. The temperature is very low in winter. In 65438+ 10, the average low temperature is about -24-29℃, the average minimum ground temperature can reach -33-37℃, and the average stable freezing period of soil is as long as 170- 175 days. Due to the low temperature in winter, it is very beneficial to organize crop diseases and insect pests to overwinter. At the same time, due to the periodic thawing effect year after year, it can promote the accumulation of humus in the soil, thus providing nutrients for crop growth.

Of course, agricultural production also has many unfavorable factors. Such as drought and flood in spring, low temperature in summer and early frost in autumn, these agricultural climate disasters are the main factors that cause the change of crop yield in our city. The soil permeability in the northern and central regions is poor. If there is a large amount of snow in winter and a lot of rain in spring, waterlogging is easy to occur, which is unfavorable to crop sowing and seedling growth, especially "early neck sticking" is the most harmful to agriculture. It's rainy in summer, and it's often cloudy with few photos. At the same time, the low temperature and insufficient effective accumulated temperature lead to slow growth and development of crops, greedy for green and late ripening, and reduce crop yield. Frost in early autumn is more common in our city, which often causes crops to suffer freezing damage before reaching normal maturity, and directly causes plant death when it is serious, thus greatly reducing production.

2. Terrain has obvious influence on climatic factors, especially on temperature and precipitation.

Southwest China is under the dual protection of Daxing 'anling and Xiaoxing 'anling. Because of the barrier function of Daxinganling, the channel of cold current is directly changed. The direction of the cold current entering from Siberia is northwest to southeast at first, and then it turns south or southwest after being blocked by the mountain, and its intensity is weakened. Due to the different mountain slopes, when cold air flows into the leeward slope, the northwest cold air drops and heats up after passing through the mountain. Therefore, the temperature in the south of our region is higher and the cold damage is reduced, which plays a protective role in agriculture in this region.

At the same time, we should also see that due to the blocking effect of Xiaoxing 'an Mountains, the ocean airflow controlled by southwest monsoon in summer is not easy to enter directly, which makes the rainfall gradually decrease from northeast to southwest; On the windward slope of the mountain range, the airflow rises and condenses when it is cold, which becomes the rainfall area in our region, with the annual precipitation reaching about 600 mm, while the prospect of Songnen Plain on the leeward slope is 400-500 mm.

In addition, because of the dense forest, it has played a great role in regulating climate, preventing mountain torrents and alleviating the effects of drought, low temperature and cold damage.

Ermohe County is the county with the lowest temperature in China and belongs to the continental monsoon climate of cold temperate zone. Due to the alternating influence of continental monsoon and maritime monsoon, the microclimate is changeable and the local climate is significantly different. Winter is controlled by the polar continental air mass, and the climate is cold, dry and long; In summer, affected by the subtropical ocean air mass, the precipitation is concentrated, the rainfall is abundant, the climate is hot and humid, and the sunshine time is long, which is suitable for the growth of cold-tolerant crops, but it is prone to floods and low temperature chilling injury. In spring and autumn, the climate is changeable because of the alternation of winter and summer monsoon. In spring, there are many strong winds, less precipitation and dry things, which are prone to forest fires; In autumn, the temperature drops suddenly, and early frost and freezing injury often occur.

The average annual temperature in Mohe County is -5.5℃. The average temperature of each month is below 0℃ for 8 consecutive months. The annual temperature is 49.3℃. The average frost-free period is 86.2 days. The average annual precipitation is 460.8 mm, and more than 70% of the annual precipitation is concentrated in July. May to June is the dry season, and July to August is the flood season. The annual average total solar radiation is 96 ~ 107 kcal per square centimeter, and the sunshine hours are 2377 ~ 2625 hours. Accumulated temperature ≥ 10℃ is 1436 ~ 2062℃.

Mohe is a permafrost region. The maximum thickness of frozen soil is below 100 m, and the maximum thawing upper interface is only about 20 cm at the shallowest part of frozen soil. The survival and growth of local wild animals and plants exceed the tolerable extreme low temperature, which becomes the limiting factor. But this is a suitable temperature range for plants and animals that like low temperature and cold tolerance.

Sanmanli City is located in the mid-latitude area and belongs to the temperate and semi-arid continental climate. Winter is cold, long and dry, and summer is short and warm. Long sunshine time and concentrated precipitation. The temperature changes greatly and too quickly in spring and autumn. It is windy and dry in spring, and the temperature in spring is higher than that in autumn.

In spring (April to May), the average temperature is between 8 ~ 10.2℃, and the average precipitation is 32 mm, which only accounts for 1 1% of the annual precipitation. Strong winds (≥17m/s) occur frequently, so there are many sandstorms. Cold, snowstorm, sleet, low temperature and other weather often appear.

The climate is warm in summer (June to August), and the average temperature is between 17℃ and 20℃. July is the month with the highest temperature in the whole year, averaging 19.4℃. The precipitation is concentrated and large, with an average precipitation of 2 12.7mm, accounting for 7 1% of the annual precipitation.

In autumn (September ~ 65438+1October), the temperature drops suddenly, and frost and cold wave appear one after another. The precipitation is obviously reduced, and the average seasonal precipitation is 42.6 mm, accounting for 14% of the annual precipitation.

Winter (11~ March) is cold and long, and cold waves often appear. January is the lowest month in a year, with an average temperature of-100 degrees.

23.8℃, the average number of days with the lowest temperature ≤30℃ in winter is 30 days, up to 53 days. The average precipitation is 1 1.6 mm, accounting for only 4% of the annual precipitation, which is suitable for smoke screen and foggy weather.