New Delhi: The Air Quality Index in Delhi has sunk to a low of 368 as measured on Thursday night and Friday morning, with the System of Air Quality and Weather Forecasting and Research (SAFAR) classifying the conditions as "very poor". The Delhi government has decided re-impose a ban on construction activities which had been lifted on November 22, following directives issues by the Supreme Court on the matter.
SAFAR's bulletin stated that the AQI would remain poor as surface winds were not picking up and carrying away polluted air as they usually would although a slight reprieve is expected on November 29. However the levels of pollution would remain high, at the upper end of 'very poor', for the next three days it warned. Local emissions and weather were the top controlling factors in the current situation the organisation said.
'Winter inversion' is one of the prime causes for AQI deterioration in the capital as during winters the air near the surface is cooler and refuses to rise up and dissipate into the atmosphere as it would in summer. This traps pollutants in the area and results in nighttime accumulation of polluted air accorind to experts. Burning of stubble, celebrations involving fireworks, construction, and increased vehicular movement are also contributing factors.
Gurugram and Noida have recorded an AQI of 350 and 463 respectively which is extremely poor. The ban on trucks entering the capital has been extended to December 3 (barring essential services), while schools and colleges are set to resume normal schedules from Monday onwards.