The average AQI of Delhi on October 31 was 117. It increased to 261 on November 1 and 324 on November 2. That is, in just two days the air of the country's capital turned from 'moderate' to 'very bad'.
AQI shows how clean or polluted the air of a place is. The more its figure increases, the worse the air is considered.
After the air quality deteriorated, the Air Quality Management Commission implemented the second phase of GRAP in entire Delhi-NCR. GRAP is a system under which different levels of restrictions are imposed as pollution increases.
At 8 am on November 3, the average AQI of Delhi increased to 330. The situation was such that in areas where people could clearly see the monuments of Delhi from their rooftops, the viewing distance reduced to less than 100 meters.
There are a total of 60 monitoring centers to measure air quality in Delhi. According to the latest update on the website, data is being received from 57 centres, while information was not coming from three.
But the question is why does the air become so bad every year as soon as winter starts in Delhi? Is the main reason for this stubble or other sources of pollution present within the capital? And are the steps taken by the government enough to stop it?
Why does pollution increase in winter?
Dr. Anju Goyal, senior researcher and associate director of The Energy and Resources Institute (TERI), says that the risk of Delhi's air deteriorating due to winter weather will remain every year.
Smoke and dust reach the air throughout the year from vehicles, factories, construction works and burning of garbage. But the speed of removal of this pollution is not the same in summer and winter.
Many times in winter, the air near the ground is cold and the air above it is hot. Because of this the air below is not able to go up easily.
If the wind speed is also low, smoke and dust start accumulating near the ground.
The direction from which the wind is coming also makes a difference. If the wind comes towards Delhi from the stubble burning areas, it can also bring the smoke there with it.
According to Dr. Goyal, the weather cannot be changed. Therefore, governments will have to reduce pollution throughout the year in those places from where smoke and dust come out.
Where does Delhi's pollution come from?
According to Dr. Goyal, Delhi's pollution is not caused only by stubble.
In his research, the share of ammonia pollution coming from agriculture was found to be 27 percent. The share of vehicles and other means of transport was 23 percent, burning of things like garbage and wood was 20 percent and dust was 17 percent.
Some fine particles reach the air directly along with smoke and dust. At the same time, some particles are formed by the mixing of different gases present in the air.
According to Dr. Goyal, the average share of stubble smoke throughout the year is about four percent. However, its effect may increase significantly on certain days.
According to data from the Center for Science and Environment (CSE), the average smoke content of stubble during October and November 2025 was 4.2 percent. For some time in November it increased to above 22 percent.
After this, in December the share of stubble decreased to only 0.2 percent. Yet the average amount of PM 2.5 in Delhi's air increased from 163 to 210 micrograms per cubic metre.
This means that even after the effect of stubble had almost ended, Delhi's air had become worse.
That is, stubble is a reason for pollution, but the entire story of Delhi's bad air cannot be understood from it. These figures are estimates of research, not a direct calculation of any one day's pollution.
Politics over stubble, but what is the real question?
On November 3, Delhi Environment Minister Manjinder Singh Sirsa accused the Aam Aadmi Party government of Punjab of promoting stubble burning.
The Punjab unit of Aam Aadmi Party rejected this allegation.
The party said that in the picture cited by the minister, the officials were not setting fire to the field, but were extinguishing it.
The party asked the BJP government of Delhi why it could not stop pollution in the capital.
But how many incidents of stubble burning took place in a state and how much of that smoke reached Delhi on a particular day, these are two different questions.
The answer to the first question can be found from the records of incidents of fire in fields.
But to know how much stubble smoke reaches Delhi on any given day, the wind direction and different sources of pollution will have to be examined.
In its order dated November 2, the Air Quality Management Commission had mentioned the weather conditions. But the Commission did not tell how much of the stubble smoke contributed to the deterioration of Delhi's air that day.
What is Delhi government doing?
Delhi government has made a ten point plan for this winter.
Under this, it has been said that fuel will not be given without valid pollution check certificate i.e. PUC at 500 petrol pumps equipped with number plate reading cameras.
The government has also announced a ban on the entry of petrol and diesel vehicles registered outside Delhi, which do not meet BS-6 standards.
The scheme, which will run from November 1 to February 28, also includes steps like repairing and cleaning roads, reducing construction dust and increasing surveillance on open burning of garbage.
Chief Minister Rekha Gupta says that better coordination between different agencies is necessary to implement these decisions on the ground.
But the question is whether these steps are enough to stop the increasing pollution in Delhi every winter?
Can only grapes clean the air?
Bhavreen Kandhari, Delhi-based environmental activist and co-founder of Warrior Moms, says that rules to prevent pollution already exist, but in many places they are not followed properly.
According to him, firecrackers continued to be burst even after Dussehra. Construction work appeared to be going on and problems like haphazard parking and traffic jams persisted.
Kandhari says that the government has held meetings with different departments, but the efforts so far are not enough.
According to him, after the bad weather, sprinkling water on the roads and applying GRAP will not solve the entire problem.
The purpose of GRAP is to take immediate action as per the level of pollution as it increases. But to reduce the real sources of pollution, work will have to be done throughout the year.
Why did the attempt at artificial rain not succeed?
Last year, the Delhi government had tried to create artificial rain to reduce the particles accumulated in the air.
According to the report of BBC Hindi dated October 29, 2025, an experiment was conducted in Delhi to cause rain by leaving fine particles inside the clouds. But it did not rain.
The Delhi government had claimed at that time that the amount of particulate matter in the air had reduced in the areas where testing was conducted.
But the reduction in the amount of particles does not automatically prove that this was due to the same test.
For this it will also have to be seen what was the speed and direction of the wind at that time. Also, what changes occurred in the air in the areas where testing was not done.
According to the World Meteorological Organization, in this technique fine particles are released inside the already existing clouds. With this, an attempt is made to influence the process of formation of water drops.
But new rain clouds cannot be created with this technique.
That means, if the right kind of clouds are not present in the sky, then artificial rain cannot be made. That is why it is not possible to use this method every time the air is bad.
What needs to be done for clean air throughout the year?
According to Dr. Goyal, the air of Delhi and surrounding areas is connected to each other. That's why Delhi cannot clean its air alone.
To reduce pollution, the governments and different agencies of Delhi and neighboring states will have to work together.
Dr. Goyal says that it is necessary to implement standards like BS-6 for vehicles.
Along with this, the system of pollution checking (PUC) of the vehicles already running on the roads will also have to be improved.
Rules to prevent dust during construction of roads and buildings will have to be followed.
She also talks about working on stoves that produce less smoke and other cleaner cooking options.
According to him, it is not easy for every family to adopt LPG. Therefore, while making any solution, it should also be seen whether people can afford it or not.
Bhavarin Kandhari also sees a political aspect of this problem.
He believes that unless pollution becomes an election issue, there will not be enough pressure on governments to solve it.
At the same time, Dr. Goyal says that governments are taking steps, but more work is still needed.
Is Delhi's air improving?
But can this be considered a substantial improvement? This figure is still more than double India's annual standard of 40 micrograms per cubic meter.
The average amount of PM 2.5 in December 2025 was 24 percent more than in December 2024.
This means that despite the improvement in the average throughout the year, the air in winter may become worse than before. In such a situation, the question is whether Delhi's air quality is really improving or is the annual average only decreasing?
And are the people living in areas like Jahangirpuri, Bawana and Anand Vihar also getting the benefit of this reform?
