What's the difference between high pressure and low pressure in weather forecast?

Air pressure refers to the pressure of the sea level atmosphere, which is caused by thermal factors and dynamic factors. Thermal factors are low expansion density and low air pressure of ground heated air, which leads to low air pressure. The ground is cold, the air density is high, and the air pressure is high, which forms a high air pressure. For example, equatorial low pressure and polar high pressure are all formed by thermal factors. Dynamic factors refer to the sinking of local airflow and the increase of air density, forming high pressure, such as subtropical high pressure area; If the local airflow rises and the air density becomes smaller, a low pressure will be formed, such as a sub-polar low pressure area. The high pressure center or low pressure center is closed and well separated. A high-pressure center with a large number of centers is a high-pressure center, and vice versa. Geography required course for senior one 1 has this.