Air quality in Delhi plunged to the ‘severe’ zone on Saturday after days in the ‘very poor’ category. However, the air is set to improve marginally over the next two days as a light drizzle is expected on Sunday morning, said Safar, a pollution forecasting agency under the Union government.
Despite the improvement, the air quality is likely to remain in the ‘very poor’ category.
Meteorologists said several parts of the city may get traces of rain during the first half of Sunday, which may briefly help clean the air. The light rain is also expected to bring a dip in the day temperature which may drop to around 18 degrees Celsius, a notch below the season’s average on Monday.
The night temperature over the next two days is expected to rise up to 9 degrees Celsius, a notch above the season’s average. High moisture content and low wind speed not allowing dispersion of pollutants trapped in the air were the major factors behind the ‘severe’ air quality, the Safar statement said.
The air quality index (AQI) was recorded as 423 at 4pm against Friday’s 371. The air is considered to be severely polluted if the value is above 400. NCR towns including Noida and Ghaziabad too reeled in the ‘severe’ category.
Concentration of PM2.5 — most prominent pollutant in Delhi’s air, however, breached the emergency mark of 300 at 7pm while PM10 levels stood at 466, close to the emergency level of 500.
In case of PM levels or AQI remaining above emergency levels for more than 48 hours, measures such as restrictions on construction and industrial activities, ban on entry of trucks kick-in. The Central Pollution Control Board (CPCB) had earlier this month imposed a day’s ban on entry of trucks within city limits.
“It would be either traces of rain or at the most a drizzle. The amount of rain would be less compared to what the city received over the last weekend. The day temperature is expected to drop to 18 degrees Celsius. Cloud layer results in a drop in day temperature while it does the opposite in case of night tempearture,” said Kuldeep Srivastava, head of the regional weather forecasting centre.
The maximum and minimum temperatures on Saturday were recorded as 22.9, three notches above normal and 7.1, respectively.
First Published: Jan 13, 2019 08:44 IST