Is the rainy sky foggy or hazy?

2. When the temperature is close to zero and the relative humidity reaches 100%, the water vapor in the air will condense into tiny water droplets suspended in the air, which will reduce the visibility of the ground. This weather phenomenon is called fog. Fog is more common in spring from February to April. When the visibility in the atmosphere is lower than 1 km due to the condensation of suspended water vapor, meteorology calls this weather phenomenon fog. Conditions for fog formation: cooling, humidifying and increasing water vapor content. The types of fog are radiation fog, advection fog, mixed fog, evaporation fog and smoke.

3. Haze is a mixture of fog and haze. When the humidity is high in the morning and evening, there are many components of fog. When the daytime humidity is low, haze is the main force, and the relative humidity is between 80% and 90%. Among them, fog is a natural weather phenomenon, and the water vapor in the air is dense. Although dust is the condensation core, it is generally non-toxic and harmless; The core substances of smog are substances suspended in the air such as smoke and dust. The relative humidity of the air is below 80% and the color is yellow. Gas can directly enter and attach to human lower respiratory tract and lung lobes, which is harmful to human health. The formation of haze weather is mainly man-made environmental pollution, and natural conditions such as low temperature and little wind make it difficult for pollutants to spread.