 Hello and welcome to NewsClick. Today we are going to discuss the reason for the pollution crisis that Delhi has faced over the last couple of weeks and what are the reasons for it and what are the long-term consequences, what are the long-term policy measures that we might need to take. To discuss this with us we have the Raghunandan who has been studying these issues for a long time and also part of the All India People Science Network. Raghun, can you tell us that a lot of these issues seem to stem from the climatic conditions or the weather conditions at this particular point of time and it seems to start with what would be the problem that has been identified as due to temperature inversion. Can you tell us what it means and what the consequences of inversion, temperature inversions are? We would know that normally in winter the cold air tends to settle to the bottom and in winter therefore you do have a cold layer but you have what is called an inversion effect. Normally you would get warm air moving upwards but in winter you get the warm air sitting there and the cold air unable to rise above it and therefore settling down at a lower level and keeping all the pollutants closer to ground than they would earlier. So you and I when we walk on the street would breathe in far more pollutants that you would in the summer when the warm air would have carried it up. So it's because the earth cools relatively and if the sun during the day is unable to cool heat the earth then that that seems to continue this problem. So there are two problems in the winter time as it is now one is the temperature effect which is the cold air staying down and the other is that if there is no wind which will actually pick up later on in the winter if there is no wind and there's still air then everything stays where it is. When the cold winter wind start blowing it will carry the pollutants away. So it will break up the inversion layer. That's right. Also there are rains. Yes the rains will bring down the particulate matter because around the particulate matter the droplets will form and they are heavy enough to bring the particulates down. However if there is no rain but there are fog conditions then what happens is you do get moisture little droplets which coalesce around the aerosols or particulate matter which makes them denser and makes them hang in the air even more. So if there's very dry wintery conditions you'll have less of this problem. If there is rains then you have less of this problem but if you have still cool air with moisture that's the worst of all possibilities which is what we are going through now. Now coming to the other issues we have been talking about daily primarily in terms of the newspapers but this has been across the whole of North India particularly starting from Pakistan as much as in up to Bihar. So this is a much larger phenomena than what people like to believe a localized phenomenon. Absolutely in fact today if you look at the pollution map of India you will find the entire northern region particularly the major towns and cities having more or less similar order of problems of pollution as Delhi. Let's just look at it quickly the aerosol map. That's right so this is the aerosol position and here is what you see throughout North India in the winter this is what you'll get. Now what happens in Delhi more than maybe in other cities is the number of vehicles that we have or the industrial pollution that we have that may be a little more in Delhi than somewhere else. Some other cities like let's say Kanpur will have more industrial pollutants less vehicular pollutants but all in all the winter conditions will exacerbate the existing high pollution levels that are there and that is why here in the map you see a big difference between the northern cities down the Indo-Gangetic Belt as you would if you go further south. That's an interesting issue that Delhi of course has seen a lot of diesel vehicles and diesel vehicles particularly prone to particulate matter emissions particularly the lower smaller sized particles PM 2.5. This is a huge problem ever since the liberalized automobile policy came into effect and diesel vehicles were given freedom to multiply and proliferate in the city without controls this problem has exacerbated but we must keep in mind a lot of the focus now is on smog and on particulate matter related pollution we mustn't forget the diesel is also the root cause of a lot of nox nitrogen oxides of carbon monoxide all of which again in the winter tend to stay at lower levels these are highly carcinogenic materials so when we talk of pollution although so much of the focus is now on PM 2.5 and particulates we should not forget that there are other deadly pollutants around which vehicular pollution particularly through diesel is causing in Delhi. Coming to the stubble burning issue which has also been the focus there has been attempt to make this the main culprit while of course it has its contribution this is not the only reason one is climatic other pollutants which are being emitted but yes you can also see the stubble burning is a particular problem that also takes place unfortunately at the same time the inversion takes place this is the extent of the problem we can see Punjab and Haryana being much more of stubble burning areas rest seems to be much less and even see you can see Pakistan though there is some stubble burning that takes place this is much less so what do you think is the reason for the stubble burning and what are the things that can be done first as you rightly said the stubble burning unfortunately takes place precisely during this time when in the early winter conditions you get the particulate settling down the stubble comes floating across from Punjab and that also settles down exacerbating this problem it will last for about a month and a bit things start getting better then everybody forgets the pollution problem despite the fact that a lot of the other pollutants are still around but the stubble issue we must understand is peculiar to our areas in Punjab and Haryana directly as a result of the green revolution because these are areas where traditionally paddy was not a major crop today it has become a major crop and a major export crop at that and there has been extensive mechanization of farming in the Punjab and in Haryana and combined harvesters are now used to cut the wheat the winter wheat crop and the paddy crop now the combined harvesters compared to the earlier traditional manual harvesting leaves a stubble of about a foot and a half whereas the earlier manual operation would have left a stubble of just a few inches above the ground which would have got plowed in to the soil for the next planting that cannot happen now the farmer has to spend a lot of money in order to clear the stall stubble maybe around in the region of 60 000 to a lakh or so and farmers today are already suffering from lack of good remunerative price but high input costs if you compel the farmer now to add more costs by putting the burden of clearing the stubble on the farmer he is unable to bear the cost he takes the easier method which is to set the stubble on fire this is what is happening unfortunately all the authorities Punjab government in the NGT everybody is putting pressure on the farmer that they should penal action should be taken on the farmer if punitive action is the only measure that you take the farmer is going to resist because he has no way of you are not encouraging compliance you are actually discouraging compliance so what you need to do is to work out both a financial as well as an institutional arrangement which will enable clearance of the stubble from the farmers fields you can recover a lot of the cost either by using the stubble for power generation there is a very fairly good tariff being offered to biomass based power generators in Punjab provided the fuel is brought to him to the power generators the same is with cardboard manufacturers the same is with pellet makers there are a lot of uses provided the government has to play an important role in facilitating meeting the costs of the farmer and setting in place an institutional mechanism which can enable clearing of the stubble and delivering it to a user okay last point the government while it has been talking about penal action against farmers and so on similar steps regarding say either vehicular pollution diesel vehicles plus also small industries where the government has been sitting on from 2014 on some of the emission norms do you see this also as a part of really looking at the weakest section in order to penalize him and other others absolutely you are now threatening punitive action against the farmer saying if you don't stop stubble burning we are going to come after you put you in jail or whatever fines and so on I don't see anybody putting a fine on a diesel vehicle on the streets of Delhi or impounding a car I don't see any construction exactly I don't see any builder being put in jail because his he is emitting construction dust I don't see the corporation bosses being put in jail because they are not doing anything about the road dust which is thrown up every day because of mismanagement and lack of infrastructure of the roads which is allowing the dust to keep circulating all day so I don't think this kind of everywhere else we talk of incentivizing the reduction of pollution but when it comes to the weakest section on whom you can take action that's the farmer you immediately jump into punitive actions this is only going to result in resistance by the farmers which may and is already starting to amount to physical resistance because there's nothing else the farmer can do thank you very much Raghu to be with us discussing these issues continue to continue to observe what is happening and come back to you for more of this kind thanks this all the time we have for news click today keep watching news click and do visit our website newsclick.in