Delhi's Faulty 'Early Warning System' For Air Pollution Remains 'Off Mark'; AQI Remains 'Poor'

Delhi's air quality early warning system (EWS) has made incorrect predictions on four of the last six days, despite using advanced atmospheric models.

The early warning system (EWS) for air quality in Delhi has made incorrect predictions on four of the last six days till Friday amid plummeting Air Quality Index in the city. Narela (330), Patparganj (309), Rohini (332), Shadipur (308), Wazirpur (354), Anand Vihar (441) recorded "very poor" air quality, according to System of Air Quality and Weather Forecasting And Research (SAFAR).

For instance on October 13, the EWS — which uses “different satellite data sets” and is “based on state-of-the-art atmospheric chemistry transport models” — predicted the air quality to be at a "moderate" level but the AQI eas well into "poor" category that day, as per a Hindustan Times report. 

The following day, it forecast an improvement but on the contrary, the national capital's AQI became worse deteriorating further into a poor zone.

Last year, the EWS had missed the signs by a wide six-day margin when the city recorded its first "severe" air pollution day on November 2. The EWS predicted the AQI would not slip into the deep red zone till November 9.

Since its launch in October 2018 to provide air quality warnings up to 10 days in advance, the EWS had a worrying track record, leaving citizens uninformed about when the precautions need to be taken and leaving authorities unable to announce curbs. 

For instance, citing EWS predictions, the Commission for Air Quality Management decided not to invoke the first stage of pollution-related curbs on October 13. However, the worsened air quality prompted CAQM to hurriedly implement the curbs the next day. 

The officials accepted that the system is not foolproof and does not adequately account for the emissions and weather factors. They also admitted that it is prone to errors when fed wrong data, especially from meteorological sources.

Run by the Indian Institute of Tropical Meteorology (IITM), Pune, and functions under the Union Ministry of earth sciences, the EWS consist of two models. 

The weather prediction model was assisted by the India Meteorological Department and an atmospheric chemistry transport model. 

Both the models determine increase or decrease in local emissions, aerosol constituents in the air,  the impact of long-range dust storms and the contribution of pollutants from farm fires. 

Delhi AQI Remains 'Poor' 

The air quality in Delhi continue to be "poor"on Saturday with an AQI of 273 as of 9 am, according to Central Pollution Control Board. A layer of smog was also visible in the city "From the past two days the pollution has increased which is causing a lot of problems...The government should take steps to control the pollution...," said a resident speaking to ANI.

An AQI between zero and 50 is considered "good", 51 and 100 "satisfactory", 101 and 200 "moderate", 201 and 300 "poor", 301 and 400 "very poor", and 401 and 500 "severe".