Poplar in the fog

(1) 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. Fog is light and heavy. When the horizontal visibility is between 1 ~ 10 km, it is called light fog; when the horizontal visibility is below 1 km, it is called fog, advection fog, steam fog, uphill fog, frontal fog and so on.

(2) How is the fog formed? Let's take a look at a phenomenon in life: when cooking, everyone can always see fog at the bottom of the pot. The formation principle of fog is the same as it, but it has a large formation range and a long duration. Air can hold a certain amount of water vapor. 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. The temperature is low in the early morning, so fog often appears in the morning. After the sun rises, due to the increase of temperature, small water droplets or small ice crystals turn into water vapor or fall to the ground, and the fog gradually dissipates.

(3) The foggy weather not only has a 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.

(4) Experts warn that the harm of fog to human health is very hidden. According to the measurement, the proportion of harmful substances such as acid, alkali, salt, amine, phenol, dust and pathogenic microorganisms in fog drops is several times higher than that in ordinary atmospheric water drops. If people exercise or walk in the fog, their breathing will deepen and accelerate with the increase of activity, so they will absorb more harmful substances in the fog and easily induce or aggravate many diseases such as tracheitis, pharyngitis and conjunctivitis. Therefore, in foggy days, people should stop some outdoor activities, especially some strenuous exercise.

(5) Since fog can do harm to people, can people eliminate it? The answer is yes, it can be demisted manually. The so-called artificial fog elimination refers to the act of eliminating fog in local areas through artificial influence to improve visibility. Fog can be divided into warm fog with temperature higher than 0℃ and supercooled fog with temperature lower than 0℃. At present, there are generally three methods to eliminate warm fog: one is heating method. Take certain measures to heat the air in the small fog area to make the fog droplets evaporate and disappear. Second, the moisture absorption method. Sowing salt, urea and other hygroscopic substances as catalysts produces a large number of condensation nuclei, and water vapor adheres to the condensation nuclei to become large water droplets. Three, artificial mixing method. Use a helicopter to fly slowly at the top of the fog area to drive the dry air above the fog top down and mix with the air in the fog to make the fog droplets evaporate and disappear.

10. The article introduces "fog" in four levels. Please use a four-word phrase to summarize the contents of Level 1 and Level 4 respectively. (2 points)

Fog formation

Hazards of fog

1 1 and (1)(3) What are the main methods of interpretation? (Name at least three) (3 points)

12 Paragraph (2) explains in what order fog forms and dissipates. (2 points)

13. When explaining the harm of fog, the article briefly describes the impact on traffic and the harm to people. What is the reason for this meticulous treatment? (3 points)

14. How do the words added in the following sentences reflect the accuracy of the language? (4 points)

(1) In foggy days, people should stop some outdoor activities, especially some strenuous exercise.

(2) According to the measurement, the proportion of various harmful substances such as acid, alkali, salt, amine, phenol, dust and pathogenic microorganisms. The carbon dioxide contained in fog drops is several times higher than that of ordinary atmospheric water drops.

Answer:

10, what is fog (definition of fog) and fog elimination (artificial fog elimination)

1 1. Define the number of categories and examples (just answer three of them).

12, time sequence

13, the impact of fog on traffic is familiar to everyone, so I will write it briefly; The harm of fog to people is very "hidden", so it is written in detail.

14, (1) "appropriate" is neither completely stopped nor unlimited, which reflects the accuracy of the language to some extent. (2) "According to the measurement" indicates that the following conclusion is a definite fact, and the source of the conclusion reflects the accuracy of the language.