Delhi: Visibility improves, air quality still 'severe'

New Delhi: Delhi witnessed a clear Tuesday morning with shallow fog while the visibility comparatively improved to 700 metres in the national capital, the weather office said. "Visibility at 8.30 a.m. was 700 metres at Safdarjung area," an official from the India Meteorological Department (IMD) told IANS. On Monday morning, visibility was 400 metres and on Sunday, it was 200 metres. The air quality, however, continued to be "severe" with System of Air Quality and Weather Forecasting and Research (SAFAR) showing levels of PM (particulate matter) 2.5 and PM 10 breaching the 500-mark at all locations. According to Central Pollution Control Board (CPCB), the Air Quality Index (AQI) for Delhi remained severe with the index value 442 at 9 a.m. "The sky will mainly remain clear during the day," the IMD official said. The humidity at 8.30 a.m. was 77 per cent. As per the IMD, the minimum temperature was recorded at 15.7 degrees Celsius, two notches above season's average. The maximum temperature is likely to hover around 28 degrees Celsius. Monday's maximum temperature was recorded at 29.2 degrees Celsius while the minimum temperature settled at 14 degrees Celsius, the season's average. Thick smog had shrouded Delhi post-Diwali and levels of particulate matter - PM 2.5 and PM 10 - breached the maximum level of 500 across the national capital. Particulate Matter less than 10 micrometres in diameter (PM10) is so small that it can get into lungs and can cause serious health problems. Particulate Matter less than 2.5 micrometers in diameter (PM2.5) is produced by burning fuels. Bursting of firecrackers, stubble burning in neighbouring states, dust from construction activities and vehicular traffic are some the reasons attributed to the sudden spike.