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Ningxia is situated in the inland of the continent, and its climate is quite arid. In winter, it is lashed by the cold currents from the northwest. In summer, the wet currents from south-east tend to end while they reach Ningxia. According to the classification of climate zones, Ningxia belongs to middle temperate continental zone. But the difference of climate between the north and south is quite extensive. It is cold and wet in the south, warm and dry in the north.

Temperature

The annual average temperature ranges between 5 - 9oC, 8 - 9oC in the north, 7 - 89oC in the central part and 5 - 7oC in the southern part, tending to be higher in the north and lower in the south. In spring, it quickly gets warm and in autumn it gets cool early. The period the temperature stays stable at 10oC is 170 days and its active accumulated temperature is 3,100 - 3300oC, 120 - 140 days in the central and the northern part, and 1,900 - 2,300oC in the southern part. Such conditions are favorable and ideal to the growth of crops and fruits.

Rainfall

The annual average rainfall is 180 ~ 650 mm, gradually decreasing from the south to the north. 400 ~ 650 mm in the south Liupanshan area, 250 ~ 300 in the central part and 180 ~ 200 mm in the northern part. Most of the rainfalls concentrate in the autumn, for the rainfall from June to September is 50 to 73% of the whole year's. The annual average evaporation is 1,300 to 2,400 mm.

Sunshine time

The annual sunshine time is between 2,214 to 3202 hours, gradually decreasing from the north to the south. The yearly radiation of the sunlight is between 130 ~ 140 kcal/cm2, which is 10 kcal/cm2 more than Huabei (North China) Plain and 30 kcal/Cm2 more than the south China. The growth period is 190 days at Guyuan and over 200 days at Yinchuan. Frost-free period is 103 ~ 148 days at Guyuan and 140 ~ 162 days at Yinchuan. The average temperature range within a day is 12.~ 15oC. The average wind speed is 1.8 ~ 3.0 m/s. Strong wind usually lasts 1 ~ 3 days, with most of such strong wind arising in spring. The prevailing wind direction tends to be northward or southward.

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