Northerly winds help improve AQI, induce dip in minimum temperatures

Responding to questions, scientists from the India Meteorological Department (IMD) attributed the improvement in air quality to changing wind directions and influx of the northerlies.

“Last week, Mumbai was reeling under high temperatures owing to the prominent Southeasterly winds, which are moist in nature. However, since Sunday, we have had the northerly wind component which has resulted in the improvement of air quality. The change in wind direction is largely responsible for the good AQI,” Sushma Nair from IMD Mumbai told the Indian Express.

Unlike last winter, Mumbai has been experiencing moderate air quality for a prolonged period this winter, a season which is typically associated with burgeoning AQI levels.

Senior scientist and project director of System of Air Quality and Weather Forecast and Research (SAFAR), Gufran Beig, attributed the good air quality to higher wind speeds and velocity.

Beig said, “This year, the surface winds are relatively high. Currently, we are in an El Nino year. This phenomenon escalates the wind speed in the western region. This is the exact opposite of last year, which was the La Nina year. Therefore, the city is experiencing relatively good air quality this season.”

According to IMD scientists, the northerlies are responsible for the declining minimum temperatures apart from improving the air quality.

Amid higher minimum temperatures, which hovered around 23 degrees until Sunday, minimum temperatures dropped significantly on Monday morning with the IMD’s Santacruz observatory recording a minimum temperature of 18.7 degrees.

“Owing to the northerlies, the temperatures will continue to oscillate between 30-31 degrees for the next couple of days, before a gradual decline. However, there won’t be a very sharp fall in temperatures,” added Nair.