What are the causes of high pressure and low pressure?

The high pressure is formed by the falling of cold air flow, the low pressure is formed by the rising of warm air flow, and the sub-high pressure is formed by the forced falling of warm air flow in the middle latitude of north and south latitudes. They only affect weather conditions and weather systems. ?

In weather forecast programs, it is often seen that meteorologists use the isobar principle to draw several numerical pressure forecast maps. As can be seen in the figure, the isobar in some areas is closed, and the central air pressure is low and gradually rises outward. People call it low-pressure area, and its spatial isobar surface is concave, similar to a basin in topography. In other areas, the isobar is also closed, but the central pressure value is higher and gradually decreases to the periphery. Such an area is called high pressure area, and the space isobar surface is convex, similar to the hills in the terrain.

In the low-pressure area, air flows from all directions to the center, which increases the air density in the center and makes the air rise continuously, and rainy weather often forms near the center. In the high-pressure area, the central airflow spreads in all directions, and the high-altitude airflow comes down to supplement, forming a downward flow, so the water vapor is not easy to condense, so the sunshine is sufficient.