What season is foggy? 、

Autumn is a foggy season. So what is fog? Fog is a phenomenon that a large number of water droplets or ice crystals are suspended in the near-surface layer, which makes the horizontal visibility less than 1 km. Fog can be divided into many kinds, the common ones are radiation fog and advection fog. Radiation fog is formed when the temperature drops by radiation at night and the water vapor in the ground air is saturated. This kind of fog mostly appears at night or in the morning, when the sun is shining, the breeze is blowing gently and the water vapor near the ground is rich. Advection fog is caused by the horizontal movement of air. Fog is also a kind of disastrous weather. Many accidents such as road traffic, flight and shipping are caused by fog. At the same time, the combination of fog and pollutants in the air will also bring great harm to people's health.

At present, fog has also been included in the "Early Warning Signal of Sudden Meteorological Disasters in Beijing", and the defense guide is given. Its specific content is: