CAQM invokes Stage III of GRAP as air pollution in Delhi-NCR rises

Amid the rise in pollution levels in Delhi the Commission for Air Quality Management (CAQM) on Friday invoked Stage III of the Graded Response Action Plan (GRAP) with immediate effect in the entire National Capital Region (NCR).

Delhi’s overall Air Quality Index (AQI) clocked at 399 on Friday as per the 4PM AQI Bulletin provided by Central Pollution Control Board (CPCB). 

"It is considered necessary to put Stage-III of GRAP back in place with immediate effect in the entire NCR in an effort to prevent further deterioration of air quality in the region," CAQM said in a statement.

Air pollution remains high across Indo-Gangetic Plains despite stubble burning from the states of Punjab and Haryana having subsided.

According to meteorologists, the absence of winter rains is keeping pollution levels high across northern states, with the Air Quality Index (AQI) oscillating between ‘poor’ and ‘severe’.

The reason for the high rates of pollution detected over North India has been identified as a phenomenon called 'winter inversion', where cooler air is trapped under a layer of warm air creating an atmospheric blanket of sorts. This has trapped pollutants closer to the Earth's surface, prohibiting them from dispersing into the upper reaches of the atmosphere.

Curbs under Stage III include a ban on non-essential construction and demolition, closure of stone crushers and mining activities in Delhi-National Capital Region (NCR).