What are the main effects of typhoon crossing the border?

The typhoon brought people abundant fresh water. Typhoon brought a lot of rainfall to the coast of China, the coast of the Sea of Japan, India, Southeast Asia and the southeastern United States.

2. Typhoon is one of the weather systems that bring heavy rain. It may produce rainfall of 150 ~ 300mm in the area it passes through, and a few typhoons can directly or indirectly produce rainstorm above 1000mm, such as the rainstorm produced in southern Henan after tropical cyclone No.3 (indirect) 1975 landed, which broke the rainfall record in some areas (Henan 70.

3. Typhoon crossing the border often brings stormy weather, causing huge waves on the sea surface, which seriously threatens navigation safety. After the typhoon landed, the storm surge may destroy crops and various building facilities, causing great losses to people's lives and property.

Causes of typhoon with extended data;

1, with pre-existing disturbance.

Typhoons are all developed from the pre-existing tropical depression disturbance. According to China's statistics, the tropical cyclones in the western Pacific-South China Sea region come from four initial disturbances in intertropical convergence zone, accounting for 80% ~ 85%; East wind wave, accounting for about10%; The cut-off low pressure in the long wave trough at middle and high latitudes, or the cold vortex at high altitude, accounts for about 5%; Baroclinic disturbance accounts for less than 5%.

2. Warm ocean surface, with seawater temperature higher than 26.5℃

The temperature and humidity of the upper and lower atmosphere in tropical oceans are mainly determined by the sea surface water temperature. The higher the SST, the higher the temperature and humidity of the lower atmosphere, and the more obvious the potential instability.

Typhoons are formed on the warm ocean surface with SST ≥ 26 ~ 27℃. Generally speaking, the global tropical ocean surface meets this condition all year round, and only the SST in the equatorial southeast Pacific Ocean is ≤ 26.5℃ all year round, which is the main reason why there are no typhoons here.

3. The vertical shear of the whole troposphere wind should be very small.

The vertical shear of tropospheric wind speed determines whether the latent heat released by convection dispersed in an initial tropical disturbance can be concentrated in a limited space.

If the vertical shear is very small, the relative motion of the upper and lower air is very small, and the latent heat released by condensation always heats the same air column in a limited range, so that it quickly heats up to form a warm center structure, and the initial disturbance develops rapidly to form a typhoon. On the other hand, if the upper and lower shear becomes larger, the latent heat will be quickly transported out of the disturbance area, and it is impossible to form a warm structure and a typhoon.

Baidu Encyclopedia-Typhoon