The air quality in Delhi and other parts of north India hit a hazardous level this month. Levels of dangerous particles in the air – known as PM2.5 – were over 10 times the safe limits in the capital. The air quality index (AQI) crossed an all-time high of 1,000 in some places on November 3. As per data, the AQI between 0 and 50 is considered safe, 51-100 satisfactory, 101-200 moderate, 201-300 poor. At 301-400 it’ considered very poor and 401-500 falls in the severe category. When the AQI crosses the 500 mark, it falls into the emergency category.
The odd-even rule, a car rationing scheme, came into effect on November 4. (As per rule, cars with odd numbers will be allowed to run on odd days such as Nov 5, 7 etc., and cars with even numbers will be allowed on even days such as Nov 6, 8, etc.). Delhi Chief Minister Arvind Kejriwal blamed crop burning in Haryana and Punjab for increased pollution levels in the capital during winter.
Air pollution is a year-round problem in Delhi due to vehicular and industrial emission, but the impact is felt more during the winter months. The capital’s low air quality during the winter is attributed to its geography, low wind speed and stubble burning by farmers in the neighbouring States of Punjab and Haryana. These farmers have come under fire for taking the air quality to a dangerous level.
Stubble burning is the practice of removing crop residue from fields post-harvest by setting fire to it. This usually happens during October and November (autumn months), as the farmers begin to prepare the field for sowing winter crops – especially wheat.
As the southwest monsoon retreats, it sets off northwesterly winds, which carry the smoke from the burning of stubble towards Delhi and other northern regions.
According to the agriculture ministry, 23 million tonnes of paddy straw is burnt in Punjab, Haryana and UP every year.
Picture Credit : Google