Common sense of meteorological disaster protection

Meteorological disaster is a kind of natural disaster with high frequency, great influence and serious harm. When disastrous weather occurs, if

Common sense of meteorological disaster protection

Meteorological disaster is a kind of natural disaster with high frequency, great influence and serious harm. When disastrous weather occurs, if preventive measures can be taken in time, losses and harm can be minimized.

tornado

1 What is a tornado?

Tornadoes are small-scale strong cyclones extending from strong convective cumulonimbus clouds to the ground. Its upper end is connected with cumulonimbus clouds, its lower end is suspended in mid-air, and some of them directly extend to the ground or water surface, and move forward while rotating. When tornadoes appear, there are often one or several funnel-shaped cloud columns like "noses" extending downward from the bottom of the clouds, accompanied by storms, lightning or hail. When a tornado passes through the water, it can absorb water and rise, forming a water column, which is connected with clouds, commonly known as "dragon absorbs water"; When tornadoes cross land, they often overturn houses, break telephone poles, and even suck people, livestock and sundries into the air and take them to other places.

2 characteristics of tornadoes

1. Tornadoes often occur in thunderstorm weather in summer, especially from afternoon to night.

2. The attack range of tornado is very small, and the diameter is generally between ten meters and several hundred meters.

3. The tornado lasts for a short time. Tornadoes usually last only a few minutes to a few minutes, not more than an hour at most.

4. The occurrence of tornadoes is random, so it is difficult to predict by conventional meteorological monitoring means.

Tornadoes are extremely powerful and destructive. The wind speed near the tornado center can reach 100-200m/s, and tornadoes often pull up trees, overturn vehicles, destroy buildings, and sometimes attract people away.

What should I do if I encounter a tornado?

1. At home, be sure to stay away from doors, windows and external walls of houses and hide in the wall or small room opposite the tornado.

2. The safest place to avoid a tornado is the basement or semi-basement.

3. In case of emergency such as pole collapse and house collapse, the power supply should be cut off in time. Prevent electric shock or fire.

4. When there is a tornado outside the scene, you should quickly flee to the opposite direction or vertical direction of the tornado and lie on the low-lying ground, but stay away from trees and telephone poles to avoid being smashed, crushed or electrocuted.

When the car encounters a tornado when going out, don't drive to avoid it, let alone in the car, because the car has almost no defense against tornadoes, so you should leave the car immediately and take shelter in a low-lying place.

The second lightning

What is the lightning of 1?

Lightning is a discharge phenomenon in the atmosphere. During the formation of thunderstorm clouds, some accumulate positive charges and some accumulate negative charges. When these charges accumulate to a certain extent, discharge will occur. Some of this phenomenon is between clouds, and some is between clouds and the earth. These two discharge phenomena, commonly known as thunder, will damage buildings and electrical equipment and hurt people and animals. This discharge time is very short, generally around 50- 100 microseconds, but the current is extremely strong, reaching tens of thousands to hundreds of thousands of amperes. When discharging, it produces strong light, which is lightning. When lightning strikes, it will release a lot of heat energy, which can instantly raise the regional temperature by 1000-20000℃ and the air pressure can reach 70 atmospheres. Such a huge amount of energy has great destructive power, which often causes fires and human and animal casualties.

What harm will lightning do?

1. Lightning generates strong current, which generates high temperature when passing through objects instantly, causing combustion and melting; Contact with people and animals will cause casualties.

2. Lightning explosion and static electricity will cause trees, telephone poles, houses and other objects to crack and collapse.

3. Lightning discharge can produce tens of thousands of degrees of high-temperature air to expand and spread rapidly, resulting in shock wave, which has certain destructive power.

4. The lightning current forms a powerful electromagnetic field in the surrounding space. Electromagnetic induction can cause spark discharge at the opening of the conductor, and if there are flammable and explosive substances, it will cause explosion or combustion.

5. All kinds of power lines, telephone lines and broadcasting lines are damaged by lightning.

How to prevent lightning strike

1. In the open field, don't make yourself a sharp edge, that is to say, try to reduce your height, and don't carry metal objects such as shovels, hoes and golf clubs on your shoulders and lift them above your head.

In the suburbs, it is best to hide in buildings with metal doors and windows or lightning rods, or in cars with metal bodies.

3. In the dense forest, it is best to find a clearing in the forest and squat down with your feet together; It is extremely unsafe to hide under the big tree to avoid the thunderstorm. In addition, don't stay under the chimneys of tall buildings and high-lying hills to prevent accidents.

4. Traveling in the mountains, such as Luyudong, can also enter the lightning protection.

When it thunders, it is best not to go fishing, boating or swimming in lakes, rivers and beaches.

6. When it thunders, it is best not to ride horses, bicycles, motorcycles or tractors in flat and open places.

7. When it thunders, the room is relatively safe, but the doors and windows should be closed to prevent dangerous side attacks and ball lightning intrusion.

How to rescue people injured by lightning?

People who are burned by lightning or severely electrocuted will not be prosecuted. Let him lie down at once, put out the fire on him and save him. If the injured person has stopped breathing or cardiac arrest, mouth-to-mouth resuscitation and cardiac compression should be carried out quickly, and they should be sent to the hospital for emergency treatment in time.

Three layers of dense fog

1. Hazards of dense fog

Shanghai has about 40 foggy days all year round, mostly in winter. When the horizontal visibility is less than 500 meters, it is customarily called fog or dense fog. The foggy weather has a serious impact on urban traffic. Due to poor visibility, the road surface is slippery, which is easy to cause crashes and accidents.

2. Protective measures in case of fog disaster

1 Try not to go out. When you have to go out, wear a mask to prevent inhalation of harmful gases.

Try to exercise as little as possible in foggy days, and don't exercise in foggy days.

Pedestrians should be careful when crossing the road and see the passing vehicles clearly.

Ride slowly and keep your vows. Don't rush by car or boat; Don't crowd the ferry when it stops.

5 When driving in foggy days, you should turn on the anti-fog lights, keep a sufficient braking distance from the vehicle in front, and keep driving slowly. It is better to drive off the road than to park in foggy weather.

Four rainstorms

1 Hazard of rainstorm

Rainstorm refers to a heavy rainstorm in a certain period of time. If the rainfall in Sichuan is above 16 mm, or 12 hour rainfall is above 30 mm, or 24-hour rainfall is above 50 mm, it is called rainstorm. Rainstorms, especially large-scale persistent rainstorms and concentrated rainstorms, often cause serious floods and losses of people's lives and property.

2 rainproof measures

1. In low-lying residential areas, measures of "small enclosure" can be taken according to local conditions, such as building fences, placing water baffles at the gate, and configuring small pumps.

2. Don't litter, sundries, etc. Enter the sewer to prevent blockage, causing water accumulation during heavy rain.

3. Power sockets, switches, etc. Residential buildings on the ground floor should be moved to a safe place above the ground 1 m. Once the outdoor water overflows into the house, cut off the power supply in time to prevent electric shock from hurting people.

4. Pay attention to observation when walking in stagnant water. Prevent falling into manholes or pits or holes.

5. The river is an important drainage channel in the city, and it is not allowed to dump garbage and waste at will to prevent siltation.

Five tropical cyclones

1 hazards of tropical cyclones

A tropical cyclone is an air vortex that occurs in tropical and subtropical oceans. Like a child's top, it turns while walking, which is one of the most destructive disasters in meteorological disasters. Its disasters are mainly caused by strong winds, heavy rains and storm surges.

2 tropical cyclone name and grade standard: for tropical cyclones, China now adopts the name and grade standard stipulated by the World Meteorological Organization, specifically:

1. tropical depression: the maximum average wind speed near the center of tropical cyclone10,8-17.1m/s.

2. Tropical storm: the maximum average wind force near the center of tropical cyclone is 8-9 wind speed17.2-24.4m/s. ..

3. Severe tropical storm: the maximum average wind force near the center of tropical cyclone is10-1and the wind speed is 24.5-32.6m/s. ..

4. Typhoon: The maximum average wind force near the center of tropical cyclone is greater than 1 2, and the wind speed is greater than 52.7m/s. ..

Since 2000, China has adopted a new tropical cyclone naming system approved by the Typhoon Committee of the World Meteorological Organization. This naming system * * * consists of five groups of 1 40 names, which can be reused. Among them, Wang Long, Wukong, Yumianya utu, Haiyan Halyan, FenSshen, Poseidon, Du Juan, Dianmu Dianmu, Haima and Haitang were provided by China.

How to prevent the destruction of typhoon

1. After the typhoon warning is issued by the Meteorological Observatory, don't go to the area where the typhoon passes or swim on the beach, let alone go sailing; People who go out should go home as soon as possible.

Residents living in the building should close the windows and take away things on the balcony, such as flower pots and clothes hangers. Reinforce outdoor objects that are easy to blow.

3. The public should pay attention to the typhoon information broadcast and released by the media and take preventive measures.

4. Clean the drainage pipes to keep the drainage unblocked.

5. Ships should enter the safe haven in time.

6. When the typhoon strikes, don't go near the window to avoid being hurt by the broken window glass.

Six high temperatures

High temperature disaster is mainly the phenomenon that people, animals and plants can't adapt to high temperature.

1 high temperature standard

When the temperature reaches or exceeds 35℃, it is called high temperature, and when it reaches or exceeds 37℃, it is called hot summer. Persistent high temperature and summer heat will make the human body unable to adapt and affect physiology and psychology, and even cause disease or death.

2 Prevention of high temperature disasters

1. Install air conditioner and electric fan to improve indoor sultry environment. But don't stay in an air-conditioned room for a long time to prevent so-called "air-conditioning diseases" such as headache and dizziness. The electric fan can't blow directly at the head or a certain part of the body for a long time to prevent the part of the body from catching cold.

When you are sweating all over, don't take a bath with cold water immediately to prevent cold air from invading your skin and getting sick. You should dry your sweat first and take a bath with warm water after a rest.

3. When the temperature is low at night, drivers should have a good rest, ensure sleep time and prevent traffic accidents caused by fatigue.

4. When the weather is hot, you should eat more salty food and drink more herbal tea and mung bean soup to supplement the water and salt lost by sweating.

5. Take proper physical exercise to enhance the heat-resistant function of human body and improve the ability to adapt to high temperature environment.