At the lower level, typhoons are mainly inflow flows to low pressure. Due to the balance of angular momentum, strong wind speed can be generated in the inner zone, and the outflow flow of anticyclone is at the upper level. The upper and lower circulations are connected by strong ascending motion, which is the main feature of typhoon circulation.

The warmest temperature in the typhoon is caused by the sinking movement. It is appearing within the inner edge of the eye wall, where there is the strongest sinking movement. At the maximum wind speed radius at the lower level of the typhoon, the convergence is strongest, and the maximum wind speed value radius changes little with the height and is located in the eye wall. In addition, the asymmetry of typhoon structure is also a feature that people have paid attention to this year. Analysis shows that there is obvious asymmetry in both the inner and outer areas of the typhoon, which plays an important role in the development of the typhoon and the transport of momentum and kinetic energy.

Typhoon in synoptic scale is a strong dynamic energy in the atmosphere, so it should have an important impact on the change and maintenance of atmospheric circulation in terms of energy. This problem has attracted people's attention. In terms of energy, it has also been pointed out this year that the horizontal vortex transport of angular momentum is very important in the outer area of the typhoon; In addition, the generation and transport of momentum in the outer region are also very important. They should not be ignored in the typhoon energy budget, which is related to the asymmetry of typhoons.