What does aql mean in the weather forecast?

Aql in weather forecast refers to air quality grade.

The air quality reflects the degree of air pollution, which is judged according to the concentration of pollutants in the air. The air pollution index is calculated according to the concentration of pollutants, in order to let the public have an intuitive understanding of the pollution situation.

Generally speaking, the monitoring department will monitor several pollutants separately and calculate the index, and choose the one with the largest index as the final air pollution index. Different countries or regions have different air pollution index calculation methods and regulations.

The air pollution index is divided into 0-50,51-100,1-150,151-200,20/kloc.

The air pollution index is 0-50, the air quality grade is I, and the air quality status is excellent. At this time, there is no air pollution problem and there is no harm to public health.

Extended data:

Air pollution index (API) is a quantitative scale method to reflect and evaluate air quality. It simplifies the concentrations of several air pollutants that are routinely monitored into a single numerical form of conceptual index, and represents the degree of air pollution and air quality according to grades. The items included in China's air pollution index are tentatively sulfur dioxide, nitrogen oxides and total suspended particles.

The calculation formula of air quality: when the concentration of a pollutant is Ci ≤Ci≤Ci, J+ 1, its pollution index Ii = [(CI-CI, J)/(CI, CJ+ 1-CI, J) ]× (II, j+1). The concentration value of the I-th pollutant in Ci;

Ii. I pollution sub-index value of pollutant J 1 1 turning point; Ci, j (corresponding to Ii, j+1) of pollutants at J turning point I; Ci, the j+l concentration value of I pollutant (corresponding to Ii, j+ 1) at the tenth j turning point; After calculating the pollution sub-index of each pollution parameter, the region or city with air pollution index API = max(i 1, I2 ... II ... in) is the largest.