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According to today's (29th Feb 2016) Evening Standard

London's air pollution 'is caused by drivers from outside the capital'

Implying that whatever London does about air pollution, there will still be a high level unless other areas control car usage etc.

(Note that London is in a “dip” and that pollution can settle for many days over London depending on the weather. For people outside of the UK, we often think of London as being everything inside of the M25, but it is not well defined what “London” means.)

Ian Ringrose
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    Can you explain whether the article means 'caused by driving that is taking place outside London' or 'caused by drivers from outside London who are driving in London'? – DJClayworth Feb 29 '16 at 13:54
  • @DJClayworth, I assume 'caused by driving that is taking place outside London' but someone will have to go back to the research the article is based on, to write a good answer. – Ian Ringrose Feb 29 '16 at 13:57
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    @IanRingrose The first sentence of the article is "More than three quarters of car pollution in the south-east is produced by drivers **living** outside London" so really the article does not say what you suggest. - and actually doesn't match the headline either – mmmmmm Feb 29 '16 at 18:01
  • The article seems to focus on carbon emissions rather than pollution (NOx and particulates) and on cars rather than buses and taxis or other forms of transport. It then makes the entirely credible observation that there are more people outside London than inside (if you stretch the outer region to the New Forest and Banbury) and that on average they drive further, so in total they emit more carbon dioxide. – Henry Mar 01 '16 at 07:50
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    It's probably true for *any* non-industrial city. The population of Washington D.C. nearly doubles between 8:00am and 5:00pm as commuters drive in from the suburbs. I imagine it's much the same for any national capitol where the main business is management rather than industry. – Joe L. Mar 03 '16 at 05:56

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It's really hard to vet an article when the only reference is to a study located behind a paywall.

The only facts the article presents include:

  • 12 million people who live outside London produced 77 per cent of the region's emmissions.
  • Those 12 million drove an average of 15.6 miles
  • The 8 million in London produced 23 per cent of the region's emissions
  • Those 8 million drove an average of 7.7 miles

I don't see support for your conclusion because the article doesn't say what percentage of the air problems are limited to London only. Which means we can't make any conclusions with regards to what will happen to London's air based on London's pollution controls. We also can't make any conclusions as to what will happen to London's air with regards to pollution controls on areas outside the city.

Once you look at these numbers a bit something interesting does pop up. The amount of emissions assigned to the two areas (in and outside London) are very close to the division of number of miles driven. People inside London drove 25% of the total miles vs 75% for people outside London.

I'd think that the variation on emissions here would be quite a bit wider (and in the opposite direction) given that people inside London tend to be in highly congested traffic more often than those outside. In other words a single mile driven in London should net a much higher level of emissions vs a single mile driven outside London. Then, again, the facts presented don't tell us where those miles where actually driven nor how they arrived at the percentage breakdown of responsibility for regional emissions.

I'm not from the area so I don't know how common it is for people outside London to drive into London and vice versa. If it is like most major cities then a fair amount of people that work in London actually live outside it; which would suggest that a large part of the problem can be resolved by London itself.

To be quite frank, what I see is an article trying to limit fallout from emissions targets not being met and obfuscating blame without giving the details necessary to support the reasoning.

NotMe
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  • This answer is based on original data analysis or non-verifiable data. It is up to the answerer to provide valid, verifiable and potentially replicable evidence. Answers which are wholly based on "original research" are generally downvoted and may be deleted. See http://meta.skeptics.stackexchange.com/q/2924 – Sklivvz Mar 03 '16 at 01:55