What is the symbol of sandstorm?

A capital S with an arrow in the middle indicates the direction of sandstorm.

The sandstorm warning in China is divided into three levels:

1, sandstorm yellow warning: 12 hours, sandstorm weather may occur (visibility is less than 1000m), or sandstorm weather has appeared and may appear and may continue.

2. Orange warning of sandstorm: Strong sandstorm weather may occur within 6 hours (visibility is less than 500 meters), or sandstorm weather has appeared and may appear and may continue.

3. Red warning of sandstorm: Strong sandstorm weather may occur within 6 hours (visibility is less than 50 meters), or sandstorm weather has appeared and may appear and may continue.

Hazards caused by sandstorms:

1, environmental pollution:

When sandstorms occur, dust and floating dust carried by strong winds are everywhere, and the number of people passing through areas with air turbidity, choking nose and eyes, respiratory tract and other diseases increases. For example,1A serious sandstorm occurred in Jinchang on May 5, 993. The dust content in outdoor air is 10 16 mm/cm3, and the dust content in indoor air is 80 mm/cm3, which is 40 times higher than the national standard for dust content in living quarters.

2. Production and life are affected.

A lot of dust carried by sandstorm weather blocked the sun, and the weather was gloomy, which led to the decrease of solar radiation. A few hours to ten hours of poor visibility can easily make people feel depressed and reduce the efficiency of work and study. In light cases, a large number of livestock can be infected with respiratory and gastrointestinal diseases, and in severe cases, a large number of "spring-deficient" livestock will die, and fertile soil, seeds and seedlings in farmland will be scraped away.

Sandstorm will also aggravate the wind erosion and desertification of the surface soil, cover thick dust on the leaves of plants, affect normal photosynthesis and cause crop yield reduction. Sandstorms also caused the temperature to drop sharply. The sky is like a parasol, and the ground becomes dark and cold in the shadow.