What's the weather like? Is it foggy?

Fog is a common weather phenomenon. When the water vapor in the atmosphere near the ground reaches saturation, a large number of tiny water droplets or ice crystal particles are suspended in the air, forming foggy days and blurring the line of sight. Meteorology calls this weather phenomenon fog.

The formation of fog contains a certain amount of water vapor in the air. The temperature is generally higher during the day, and more water vapor can be contained in the air; But at night, the loss of ground heat reduces the ground temperature, and at the same time affects the air layer near the ground, so that the air temperature is also reduced. When the temperature is so low that the air can't hold all the original water vapor, the excess water vapor condenses into small water droplets or ice crystals and floats in the atmosphere near the ground, forming fog.

Fog weather not only has great influence on traffic, but also harms agriculture. If it is foggy for several days, it will make crops lack light, further affect crop growth and induce diseases. If wheat is foggy for more than 3 days when heading, it is easy to cause scab.

Fog is also very harmful to human health. It is determined that the droplets contain many harmful substances such as acid, alkali, salt, amine, phenol, dust, pathogenic microorganisms and so on. If people exercise or walk in the fog, they will absorb harmful substances in the fog, which will easily induce or aggravate many diseases such as tracheitis, pharyngitis and conjunctivitis.

Since the fog will do harm to people, it can be eliminated manually. The so-called artificial fog elimination refers to the act of eliminating fog in local areas through artificial influence to improve visibility.

There are two ways to eliminate fog drops: one is evaporation; The other is precipitation droplets.

The first method to evaporate fog drops is to raise the temperature, that is, to burn various fuels such as oil to evaporate fog drops; Secondly, dry air outside the fog is mixed into the fog to reduce the relative humidity of the air in the fog, so that the air in the fog changes from the original saturated state to unsaturated state and the fog droplets evaporate.