The horizontal bar charts illustrate the daily average of low and high levels of air pollutants in four major cities in the year 2000.
Overall, Mexico City has an equal proportion of both the pollutants, NO2 and SO2, in its air, which is the highest amount among other cities, while Los Angeles has the lowest amount of nitrogen dioxide and sulfur dioxide in its air.
Specifically, max SO2 in Los Angeles’s air was lower than other cities, while NO2 was ten times higher than SO2 in Los Angeles. Only Calcutta was a city that never exceeded the 100-microgram limit. Beijing’s maximum SO2 was four times more than its minimum S02.
In Mexico, the SO2 level was 200 micrograms and the N2O level was 207 micrograms, which is double Los Angeles’s maximum N2O and Beijing’s maximum SO2. Minimum N20 in Mexico was 113 micrograms, and minimum SO2 was 80 micrograms.