The bar chart compares the average daily minimum and maximum concentrations of SO2 and N2O in four cities in 2000.
Overall, Mexico City recorded by far the highest pollution levels for both gases, whereas Los Angeles had the lowest figures, particularly for SO2.
In terms of SO2, Los Angeles had the lowest readings, with a minimum of just 2 micrograms per cubic metre and a maximum of 10. Calcutta showed moderate levels, ranging from forty seven to 59, while Beijing recorded a wider gap between its minimum of 25 and maximum of 100. Mexico City stood out significantly, with levels reaching 200 at maximum and 80 at minimum air pollution.
Regarding N2O, a similar pattern can be observed. Mexico City again had the highest figures, at 113 minimum and 207 maximum. Los Angeles recorded relatively high N2O compared to its SO2 levels, while Calcutta and Beijing remained at moderate levels.
