Delhi has been battling hazardous levels of pollution for the past few days. So much so that the national capital has received the tag of the most polluted city in the world, beating Beijing. In the last few days, Delhi has seen it all, right from the battle over implementation of the odd-even policy to the petition of banning diesel cars from the city.
However, since Sunday, pollution levels in Delhi-NCR have gone down significantly. This change can be attributed to the dry northwesterly winds, which have brought down the humidity levels significantly. The situation has improved fairly since the past few days.
The problem of pollution in Delhi-NCR usually aggravates during winters due to the formation of smog (smoke + fog). During the winter season, when temperatures decrease, humidity levels soar due to the effect of active Western Disturbances in the hills of North India.
Thus, the usual pattern of north-westerly winds is replaced by easterly or south-easterly winds and the wind speed also reduce significantly. This entire process results in the formation of fog. The industrial and vehicular pollution in combination with dust from construction sites further resulting in smog over the city.
Due to light and variable winds, smog persists for a longer duration. At times, similar situation prevails for many days as well. However, whenever strong north-westerly winds start blowing over Delhi, due to dryness, the smog is carried away. Also, humidity levels decrease and moderate winds do not allow the formation of fog.
Currently, Delhi-NCR is observing clear mornings and there has been a significant reduction in the pollution levels. As per Skymet Meteorology Division in India, north-westerly winds will continue to blow for another 4 to 5 days, and Delhiites will breathe cleaner air.
Image Credit: indiatoday.in
