Winds pick up to disperse pollutants
NEWDELHI: A slight increase in the surface wind speed and higher day temperature in the national capital on Sunday helped pollution levels improve a little further.
With the return of northwesterly winds, which are strong and cold, air quality is likely to improve further, and the day temperature is expected to drop by a degree or two. Similar conditions are likely to continue over the next two days, said scientists at the India Meteorological Department (IMD).
The 24-hour average air quality index (AQI) reading, as calculated by the Central Pollution Control Board (CPCB)’S 4pm bulletin, was 330 on Sunday, a slight improvement from 334 on Saturday.
“Air quality is likely to improve further because of the approaching western disturbance in the northwestern region. It is likely to induce rainfall and strong winds on January 7-8, and will help clear the air of pollutants,” said Kuldeep Srivastava, head of IMD’S regional weather forecasting centre.
The average surface wind speed on Sunday was 15-16 kmph. Though the day temperature was 21.2 degrees Celsius, two notches above normal, there was a nip in the air. This is mainly because northwesterly winds have returned, which are stronger and colder than the easterlies that had been blowing over Delhi for the past few days, Srivastava said.
The minimum temperature was 7 degrees Celsius, normal for this time of the year.
“With the western disturbance, the day temperature will drop to around 19 degrees Celsius over the next two days. But the minimum temperature will rise during this time. After the western disturbance passes the night temperature will see a drop from January 9,” he added.
The System of Air Quality and Weather Forecasting and Research (Safar), the weather and air quality forecasting centre of the ministry of earth science, has forecast that surface winds have started to pick up and wind direction has also changed from easterly to westerly. “Under the influence of a fresh western disturbance, increased surface winds and an increase in minimum temperature is forecast for the coming days,” a senior Safar scientist said.