Typhoon prevention measures
1 and may or have been affected by tropical cyclones within 24 hours, and the average wind force along the coast or land is above 6, or the gust is above 8 and may continue.
1 *** and relevant departments shall prepare for typhoon according to their duties;
2. Stop outdoor collective activities and dangerous outdoor operations such as high altitude;
3. Take active measures for water operations and passing ships in relevant waters, such as returning to Hong Kong to avoid the wind or detour;
4. Strengthen doors and windows, hoardings, scaffolding, billboards and other structures that are easily blown by the wind, and cut off dangerous outdoor power supply.
It may or has been affected by tropical cyclones within 24 hours, and the average wind force along the coast or land is above 8, or the gust is above 10 and may continue.
1 *** and relevant departments shall prepare for typhoon emergency according to their duties;
2. Stop outdoor dangerous operations such as indoor and outdoor large-scale * * and high altitude;
3. Take active measures for water operations and passing ships in relevant waters, strengthen port facilities, and prevent ships from anchoring, grounding and collision;
4. Reinforce or dismantle structures that are easily blown by the wind. Personnel should not go out at will, ensure that the elderly and children stay in the safest place at home, and the dangerous house personnel will be transferred in time.
Within 3 12 hours, it may be or has been affected by tropical cyclones, and the average wind force along the coast or land is above 10, or the gust is above 12 and may continue.
1 *** and relevant departments shall do typhoon prevention and emergency rescue work according to their duties;
2. Stop large-scale indoor and outdoor * * *, and suspend classes except for special industries;
3. Relevant emergency departments and emergency rescue units should strengthen their duty, closely monitor the disaster situation and implement countermeasures;
4. Ships working on water and passing through relevant waters should return to Hong Kong to take shelter from the wind and strengthen port facilities to prevent ships from anchoring, grounding and collision;
5 When strengthening or dismantling structures that are easily blown by the wind, personnel should stay in windproof and safe places as far as possible. When the typhoon center passes by, the wind will decrease or stay still for a while. Remember that the wind will suddenly blow, they should continue to stay in a safe place to avoid the wind, and dangerous people should move in time;
Relevant areas should pay attention to prevent flash floods and geological disasters that may be caused by heavy precipitation.
Conditions of typhoon
Judging from the typhoon structure, such a behemoth must have unique conditions.
First of all, there must be a vast atmosphere with high temperature and high humidity. The temperature and humidity of the bottom atmosphere on the tropical ocean surface are mainly determined by the sea surface temperature, and typhoons can only form on the warm ocean surface where the sea surface temperature is higher than 26℃-27℃ and the sea surface temperature is higher than 26℃-27℃ within 60 meters.
Second, there should be an initial disturbance in which the lower atmosphere converges to the center and the upper atmosphere spreads outward. Moreover, the divergence of the upper layer must exceed the convergence of the lower layer in order to maintain enough updraft and continuously strengthen the disturbance of the lower layer;
3. The difference of vertical wind speed should not be too big, and the relative motion of the upper and lower air is very small, so that the latent heat released by water vapor condensation in the initial disturbance can be stored in the air column in the typhoon eye area, forming and strengthening the typhoon warm center structure;
Fourth, there must be enough geostrophic deflection, and the earth's rotation is conducive to the formation of cyclonic vortices. The geostrophic deflection force is close to zero near the equator and increases at the north and south poles. The typhoon occurred on the ocean surface about 5 latitudes from the equator.
The tremendous energy contained in typhoons.
The huge energy contained in a typhoon can be explained by the precipitation it brings. According to the research, a typhoon with an average of 1 day can drop 15mm within the radius of 665km, that is, 2.1×16cm3, and the latent heat released by so much precipitation is 5.2×10/kloc.
The huge energy contained in a typhoon can also be explained by the kinetic energy of wind energy brought by its strong wind. Assuming that the average wind speed of a mature typhoon is 40m/s within a radius of 60km, the energy required to maintain such a strong wind is about1.5×1.01.2wt, which is equivalent to half of the global power generation, which is also amazing!
The omen of typhoon
There are signs before the weather changes, and before the typhoon comes, it is no exception. In summer, we are mostly affected by the Pacific high, and the wind is mostly southerly, and the wind is weak. When the typhoon approaches, the outermost circulation will arrive first. At this time, the wind direction affecting Taiwan Province Province will change from the original southerly wind to the northerly wind, and due to the downward airflow around the typhoon, the visibility will often become very good two to three days before the typhoon comes, and mountains and trees in the distance can be seen clearly. In addition, before the typhoon comes, the outermost downdraft zone will arrive first, and the clouds will not develop easily in the afternoon, so the thunderstorm will stop. Therefore, if this phenomenon occurs in the mountainous areas for several days in summer, we should be more vigilant.
Two or three days before the typhoon comes, due to the north wind blowing, the situation of land and sea winds will become inconspicuous. Two or three days before the typhoon comes, when the sun sets below the horizon, it will send out several red and blue rays under the western horizon. This phenomenon is called anti-twilight.
In the cloud part: When cirrus clouds appear in the sky and gradually thicken into cirrostratus, the clouds gradually decrease, which means that a typhoon is approaching somewhere. If the typhoon approaches, showers will come and go, and the frequency will be higher and higher, which also means that the typhoon is close to Taiwan Province Province and will attack Taiwan Province Province. If you are still in the mountains at this time, you should go down the mountain as soon as possible.
As far as the seaside is concerned, the summer wind is very weak and the waves are very small. If a typhoon approaches in the distance, the long wave caused by the typhoon will spread to the seaside first. In the eastern coastal areas, long waves are often seen when typhoons approach in summer. Don't watch the waves near the seaside to avoid danger.