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Sunlight, faster winds improve air quality in Delhi
New Delhi
New Delhi
Reduced fog, good sunlight and winds picking up pace helped improve air quality in the national capital from being in the very poor zone to poor on Thursday.
The air quality index (AQI) as calculated by the Central Pollution Control Board’s (CPCB) 4pm bulletin was 211, as compared to 370 in ‘very poor’ category, the previous day.
India Meteorological Department (IMD) scientists said average wind speed of about 20-25kmph helped disperse pollutants accumulated in the air.
“With the fog layer reducing and the sun shining bright, the mixing height (circulation in the air allowing ventilation) came up, allowing the air to clear. In addition to this, the high wind speed further helped in dispersion of concentrated pollutants,” said a senior IMD scientist.
Strong winds are expected to blow over Delhi on Friday as well. However, ‘moderate’ to ‘dense fog is expected to return to Delhi on January 26-27.
Meanwhile, city’s minimum temperature on Thursday was 9.1 degrees Celsius, a notch above the season’s average. However, the maximum was 20.2 degrees C, a notch below normal.
“The mercury is expected to drop slightly around January 28-29 when there is a possibility of rain and thunderstorm,” he added.
According to the Union ministry of earth science’s System of Air Quality and Weather Forecasting (SAFAR), the high surface winds are the main factor contributing to the improvement in air quality through high ventilation.
“SAFAR forecast suggests the strong westerly surface winds are likely to continue till Friday. However, air quality is likely to deteriorate on January 25-26, as wind swill slow down and fog will return,” it said.
