A Meteorological explanation for the Air Quality over Mumbai:

 Last 15 day Mumbai  continuously >36°

A Meteorological explanation for the Air Quality over Mumbai:

The red line shows temperature variation with height. We can see temperature inversion in this case, i.e., temperature rises with height for few hundred meters above the ground before dropping above it.

This phenomenon happens every time during the winter months, wherein the air near the ground cools and this cool air near the ground is trapped below a layer of warm air. As warm over cool structure is stable, there is no vertical mixing of air. 

Therefore, all the particulate matter/pollutants get trapped in this low, near surface layer of air. Often, fog/mist forms when windspeed is low (seen in rural Konkan belt), but in cities, pollutants cause the fog to become smog/haze. When windspeed in the lower 2-3 km of the atmosphere is less, the pollutants do not disperse and this phenomenon persists.

Air quality only improves during the post-Monsoon or winter months when there is strong wind (which usually happens due to passage of a Western Disturbance or some other weather system) or after some rainfall, which is rare from mid October to February.

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