Delhi's air quality remained poor for the second day due to change in wind direction, which is now flowing from the stubble burning areas, authorities said Saturday.
The overall air quality index (AQI) of 245 was recorded at 10 am Saturday which is the poor category.
Ghaziabad and Gurgaon recorded 'very poor' air quality at 302 and 336 respectively, according Central Pollution Control Board (CPCB) data. Yesterday, the AQI of Delhi was registered at 259.
Earlier, it was predicted that a dust storm will hit the national capital which would further deteriorate the air quality, but, at present, there are no indications of a big storm. Authorities are closely monitoring the situation, a senior official at the Supreme Court mandated body Environment Pollution Control Authority said.
The drop in the air quality is due to change in direction of wind, which is now flowing from areas in Haryana and Punjab where stubble burning is taking place, a CPCB official said.
"This is the period of monsoon withdrawals and a low pressure system in the Arabian Sea is developing. Such large scale processes tends to calm the wind speed which is usual for this time.
"This tends to increase pollution level. The impact of local transport is insignificant so far," Project Director at the Centre-run System of Air Quality and Weather Forecasting and Research (SAFAR), Gufran Beig, said.
An AQI between 0-50 is considered good, 51-100 satisfactory, 101-200 moderate, 201-300 poor, 301-400 very poor, and 401-500 severe.
The PM10 level (presence of particles with diameter less than 10mm) was at 208 in Delhi and the PM2.5 level (presence of particles with diameter less than 2.5 mm) in the city was 104, according to a data by SAFAR.