Air quality to deteriorate during winters, a common phenomenon: Experts

As chilly winds enter parts of Maharashtra, temperatures have dropped across the state. In Mumbai, the minimum temperature dropped for the second day in a row on Saturday, December 5.

The India Meteorological Department (IMD) recorded a minimum temperature of 18.4 degree Celsius which is 1.4 degrees below normal and the seasons lowest so far on Saturday. However, on the grimmer side, during the cold winter months, particulate matter and carbon monoxide pollutants from wood-burning increases. Moreover, with the resumption of activities in the state after the relaxations in the lockdown norms, the air quality index has deteriorated.

In an effort to understand the impacts of the winter on the worsening air quality, the team of Mumbai Live got in touch with Doctor Gurfan Beig from System of Air Quality and Weather Forecasting And Research (SAFAR). Doctor Beig speaking about how cooler temperatures deteriorate air quality, stated, “During the winters, the air becomes heavier and its holding capacity increases. Secondly, there’s this thing called the inversion layer or boundary layer, which separates our atmosphere from the upper atmosphere. This layer prevents the air below it from rising, thus trapping any pollutants that are present,”

Further speaking about whether the poor air quality index was due to the relaxations in the lockdown norms, he stated, “This happens to be a normal phenomenon. Every year around this time, especially in the months of December and January, it is a little difficult. There is nothing specific to the lockdown about this, however, had there been a lockdown during this period, the pollution would have come down definitely,”

The Air Quality Index earlier recorded in Mumbai back in November was 252 which falls under the poor category. The AQI values at or below 100 are generally thought of as satisfactory. However, when AQI values are above 100, air quality is unhealthy. From 201 to 300, the air is judged to be very unhealthy; children, asthmatics and people with heart or lung conditions should avoid the outdoors and all others should reduce their outdoors exertion. On the other hand, when the AQI exceeds 300, it is “hazardous” for everyone to venture outdoors.