Why doesn't Yuanmou rain?
Since 2009, severe meteorological drought has occurred continuously in Chuxiong Prefecture, which has brought great difficulties to agricultural production and people's lives. What causes the current drought in Chuxiong? According to the analysis of meteorologists, the drought in Chuxiong for three consecutive years was caused by the following reasons:
Seasonal drought: The monsoon climate in Chuxiong Prefecture has obvious characteristics. Every winter and spring season (165438+ 10 to April of the following year) is in dry season, with scarce natural precipitation and large evaporation, which is prone to meteorological drought. There have been 35 droughts in * * * since meteorological data were recorded, accounting for 70%, which is a high frequency of meteorological disasters.
Abnormal atmospheric circulation: the intersection of cold air and southwest warm and humid air flow is the main circulation form that produces large-scale precipitation, that is to say, the above two conditions are indispensable to produce large-scale precipitation. In recent three years, due to the influence of abnormal atmospheric circulation, when the cold air in the north often affects our state, the water vapor in the Bay of Bengal in the south can't be transported out, or there is no influence of cold air when the water vapor is sufficient, resulting in less continuous rainfall, higher temperature and rapid development of drought. At the same time, due to the abnormal atmospheric circulation, a large area of drought occurred in most parts of the province and Guizhou, Sichuan and other provinces.
The superposition of less rainfall in three years leads to the continuous aggravation of the drought: since 2009, due to the abnormal atmospheric circulation, the precipitation in our state has been less for three consecutive years, of which the annual precipitation in 2009 and 20 1 1 year is the lowest since meteorological data were recorded, the annual average rainfall in the whole state is only 6 14 mm, and the annual average precipitation in Chuxiong state is 850 mm, and the annual average precipitation is 850 mm.
It can be seen that seasonal drought, abnormal atmospheric circulation and continuous low precipitation in recent three years are the reasons for Chuxiong's current drought.