Meteorological index of urban disasters

In order to show the correlation between urban meteorology and people's lives and meet people's different needs for meteorological forecast, meteorological departments have defined various meteorological indexes.

(1) human comfort index

See table 1 for the direct feelings brought by meteorological conditions.

Table 1 Human Comfort Index Index Grading Human Comfort Feeling 86 ~ 88 4 Human body feels very hot and uncomfortable, so we should pay attention to heatstroke prevention and cooling to prevent heatstroke 80 ~ 85 3 Human body feels uncomfortable with heat, and we should pay attention to heatstroke prevention and cooling 76 ~ 79 2 Human body feels very uncomfortable with heat. The temperature can be reduced appropriately: 7 1 ~ 75 1, making people feel warmer and more comfortable; 59 ~ 700, the human body feels most comfortable; 5 1 ~ 58- 1, the human body feels slightly cooler and more comfortable; 39 ~ 50-2, the human body feels cold (cold) uncomfortable. Please keep warm from 26 to 38-3. People feel very cold and uncomfortable, so please pay attention to keep warm and prevent colds. < 25-4. People feel extremely uncomfortable when they are cold (cold). Please keep warm to prevent frostbite. (2) Meteorological index of morning exercise.

According to the sky conditions, wind power, temperature, air pollution degree and other conditions, the standard of meteorological elements outside the morning exercise is formulated, as shown in Table 2.

Table 2 Fitness Description of Morning Exercise Meteorological Index Grade 1 Very suitable for morning exercise, with good meteorological conditions. Grade 2 is suitable for morning exercise, grade 3 is suitable for morning exercise, grade 4 is not suitable for morning exercise, grade 5 is not suitable for morning exercise, and all meteorological conditions are not good. (3) Wind chill index.

The cold sensation index caused by weather factors such as sunny rain, wind, temperature and humidity and air pressure is comprehensively considered. Wind chill index is the refinement of comfort index in autumn and winter. Because the temperature changes greatly in autumn and winter, the human body is more sensitive to factors such as snowy weather and humidity than in warm season. The wind chill index comprehensively considers the influence of temperature and wind speed on human body, and people can take corresponding cold-proof measures according to the wind chill index. Take the wind chill index of Beijing as an example, see Table 3.

Table 3 Daily average temperature (℃) of wind chill index in Beijing: human perception 1, 0 ~ 5, cold 2-0. 1 ~-4.9, cold 3-5 ~-9.9, cold 4-5 ~-9.9 (wind force is greater than 4), and cold 5 is lower than-10.

Air pollution index is a set of numbers to evaluate air quality, which can represent whether the air is clean or polluted. The air pollution index focuses on the possible impact on human health within hours or days after inhaling polluted air. The air pollution index is divided into six grades, corresponding to the six grades of air quality. The greater the index, the higher the grade, indicating that the more serious the pollution, the more obvious the impact on human health, as shown in Table 4.

Table 4 air pollution index air pollution index air quality level pollution situation has no effect on human body. 0 ~ 50 is excellent in the first grade, 5 1 ~ 100 is good in the second grade, and there is no significant effect.1kloc-0/~150 is irritating to people who are sensitive to light pollution in the third grade. 438+0 ~ 200 mild pollution healthy people have irritation symptoms; 20 1 ~ 300 five-level moderately polluted healthy people generally have irritation symptoms; 30 1 ~ 500 level 6 heavily polluted healthy people have severe irritation symptoms.