The Delhi Pollution Control Committee (DPCC) on Thursday told the Delhi High Court that the ambient air quality in the year 2015 was not as bad as the previous four years.
A division bench of Justice B.D. Ahmed and Justice Sanjeev Sachdeva, which is hearing a PIL initiated by it on its own on the issue of air pollution in the capital, was told though last year was relatively a better year in terms of pollution index, it did not mean the situation was great.
The panel in its report to the high court said that Delhi generally witness three pollution peaks in a year, one in summer season - May or June - and two peaks in winter - the first in October to November and the second in December.
Mohan P. George, a senior scientist at DPCC, said large scale burning of agricultural residue in the neighboring state such as Punjab and Haryana are significant contributory factor to pollution peaking in winter.
"It is needless to add that Delhi air is part of Air Shed which covers neighboring states. Hence Delhi and neighboring states affect each other from air quality point of view," the report said.
It further said that in October-November, the pollution level was at a higher level due to burning of biomass and crops in neighbouring states, while in December-January it was on account of temperature inversions and in May-June, due to dust storms emanating from Rajasthan.