The System of Air Quality And Weather Forecasting And Research, a Centre-run agency that monitors air pollution, has said that a dust storm in West Asia contributed the most to the smog that enveloped the National Capital Region last week, PTI reported.
On November 8, 40% of the smog was due to the storm while emissions from burning stubble contributed 25%, the Pune-based agency said in a report accessed by PTI.
“Rest was made up of emissions from local sources such as vehicular combustion,” the report said. “If external sources did not have any role, levels of PM 2.5 during this period could have been around 200 µg/m3 [micrograms per cubic metre of air].”
The 24-hour standard for the particulate matter is 60 ug/m3.
The emergency measures such as ban on the entry of trucks and construction activities reduced pollution by 15%, the agency noted.
Delhi and several parts of North India have been covered in a toxic smog since November 7, leaving the governments of the National Capital Region scrambling to bring in measures in the eleventh hour to bring down pollution levels. This had happened in 2016 as well.