India, Sept. 23 -- With the onset of cooler weather, Delhi is once again preparing for the seasonal surge in air pollution that has become a recurring public health crisis. Capital's air quality could deteriorate sharply in the coming weeks as emissions from vehicles, industry, and stubble burning combine with stagnant weather conditions.

Data from the Central Pollution Control Board (CPCB) shows that pollution levels begin climbing in late September, peaking between October and January when low wind speeds and temperature inversion trap pollutants close to the ground.

Last year, Delhi recorded "severe" air quality on multiple days, forcing school closures, flight disruptions, and restrictions on construction and traffic.

One of the bi...