About blocking high voltage

These are all professional problems of meteorology. If you have the conditions, I suggest you look at the textbooks on meteorology.

Here I just give a brief introduction, not a standard, for reference only.

1. The blocking high pressure is due to the warm advection northward behind the westerly ridge at high altitude (referring to the northern hemisphere). When the latitude reaches a certain level, its warm air supply will be cut off by cold air, so that this warm air will be surrounded by cold air to form a blocking high pressure. Because the blocking high pressure is warm, the main factor affecting the collapse of the blocking high pressure is the intrusion of cold advection at the back (west) of the blocking high pressure, which makes the blocking high pressure collapse, and the temperature trough invades the blocking high pressure in the high altitude map; There is also the adjustment of the overall atmospheric circulation, which makes the blocking high pressure unable to maintain and die out; Because the supply of warm air blocking high pressure will be cut off, unless the supply of warm air continues, the blocking high pressure will collapse.

2. The blocking high in Wushan is maintained near Wushan on average. Because blocking high pressure is cold advection at the front and warm advection at the back, and blocking high pressure is often accompanied by cutting off low pressure or polar vortex, it is likely to form a transverse trough, so the cold advection in front of the ridge will accumulate behind the transverse trough due to the action of the transverse trough, forming a cold source. The average position of the transverse trough formed is from western Siberia to central Siberia. These areas are cold in winter, and the cold advection makes these areas transverse. When Wushan collapsed, the horizontal trough could not be maintained, which turned it into a vertical trough, and the accumulated cold air would be driven southward under the action of airflow behind the vertical trough, forming a cold wave.