h2g2 The Hitchhiker's Guide to the Galaxy: Earth Edition

Entry: Atmospheric Pollution from the Internal Combustion Engine in the Urban Environment - A3421289
Author: TRiG (Ireland) [I can't explain anything] - U612575

Third time lucky?

Once more into the breech, dear friends, once more.

First PR thread: F48874"?thread=550173
Second PR thread: F48874

Footnote 11 has a cold in it's nose.

Your syllogism about diesel being the most polluting is missing a step or two, I couldn't make any sense of it.

Pardon?

Does anyone have any suggestions on how this could be improved to qualify for the Edited Guide? I didn't quite get what Sea Change was saying.

TRiG_Ireland.

'cold in its nose...'

What seachange means is that you've written "This means that a fairly small amound of it can do a lot of damage." instead of ...amount... so it sounds like the person saying it has a cold in their nose.

I think.

I have difficulty understanding your writing TRIG, so it's very likely I am not making myself clear.

I wasn't sure what you meant by the sentence with 'amound' in it so I wasn't sure if it were a mispelling. That you didn't see it right away after I mentioned it probably means you meant something different from what I read.

Your paragraph on benzene rings, which segues immediately into diesel, reads to me in a pattern like this: If all A are B, and all B are C, then all A are C. But, it is not logical to me if I read it that way. So I do not know your intention and can't comment on it except that it looks odd.

Hiya,

Interesting article... I can't comment on the chemistry as I'm not a chemist, however there is one thing I want to point out.

Lumping diesels in with 4x4s isn't necessarily accurate. Diesel is used in lorries, trains and buses (public transport*) as well average passenger cars from the small city cars right the way up to executive motors. In Europe, more new cars sold are diesel than petrol now (although I can't recall the exact figures . May be worth Googling or checking on the SMMT website if you want the figures).

*and on most of the buses and trains I see, they're belching out black smoke either through poor maintenance or something else.

Agreed, driving a 4x4 in town is a status symbol, but no dumber than most of the other measures of status around. Also, a lot of these 4x4s are petrol, not diesel - for example, well over half of all Range Rovers built are petrol.

Diesel particulate filters are now mandatory anyway with the advent of the Euro IV emissions standards. In terms of CO2 emissions, diesel cars are better than petrol counterparts, but I don't know how this stacks up against the rest of the emissions.

Your article came across in some ways as anti-diesel and anti-4x4, and in the latter case it seemed to be because of media propaganda rather than anything solid.

Also hybrid vehicles are not the panacea they may appear to be; only in city, stop-start traffic do they offer great advantages. On motorways and fast A-roads they're actually worse than their petrol equivalents (the Lexus RX400h is an example). They're a start, but not perfect.

Sorry, you hit on a few of my personal bugbears in this article!

Good luck with getting the article out .

I've fixed amound/amount. I didn't catch it earlier because I'm lousy at proofreading my own work (proofreading other people's work is a different matter entirely!). I'm not doing anything else tonight because I'm tired.

It is possible that some of this info is out of date.

If my writing is hard to understand that's a major flaw.

Keep up the suggestions, folks! They will be implemented in due course.

Thanks.

TRiG_Ireland.

Okey-dokey, then!

These sentences could be simplified:

Hence motor fuel contains hydrocarbons and organic compounds4 containing nitrogen and sulphur. When these are burned in air the products are water, carbon di- and monoxide, and oxides of nitrogen. Nitrogen gas in the atmosphere can also react with oxygen at the high temperatures in the combustion chamber.

>Hence motor fuel contains hydrocarbons and OTHER organic compounds4 containing nitrogen and sulphur. When these are burned in air the products are water, carbon monoxide, carbon dioxide, and various oxides of nitrogen. Nitrogen gas in the atmosphere can also react with oxygen at the high temperatures in the combustion chamber to form various oxides of nitrogen known collectively as NOx.



CO is highly toxic: haemoglobin will pick it up in preference to oxygen11, so that less oxygen reaches body cells.

> CO is highly toxic: it binds to haemoglobin more strongly than oxygen, thus reducing the capacity of the haemoglobin to carrying oxygen.


Other oxides of nitrogen may occur, but are more rare.

> Other oxides of nitrogen, such as N2O4, may occur; but are more rare.



SO2 is an acidic pollutant which dissolves in moisture in the atmosphere to form sulphurous and sulphuric acids (components of ‘acid rain’).

> SO2 (and SO3) are gases which dissolves in moisture in the atmosphere to form sulphurous acid, (H2SO3) and sulphuric acid (H2SO4) respectively, thus causing ‘acid rain’.


SO2 is a component of ‘classical’ smog (as exemplified by London in the 1950s (?check dates)).REMEMBER TO CHECK DATES.

Your Entry makes no mention of PM10 particles. These are particles of diameter less than 10 millionths of a metre (i.e. <10 microns). These are small enough to penetrate to the deepest recesses of our lungs. Normally we inhale around 500,000 such particles/breath, but in times of heavy pollution this may increase 100-fold (i.e. to 50 million). Some experts believe that these may be responsible for up to 1000 deaths/year.

One third of PM10's in urban air is from diesel vehicles. In towns, diesel is the biggest single source.

The increasing level of fine particles in the air has been linked to the increase in the incidence of asthma, which currently afflicts approximately 10% of children.

There is scope for links, e.g.

Asthma A408818
Global Warming A197499

Oh, and on this reaction sequence:

NO2 --> NO + O
O + O2 --> O3
O3 + NO --> O2 + NO2

you need to put 'dots'; next to the O's to indicate that they are free radicals. (I don't know iof there is a mechanism in GuideML for exaggerating these dots to make them more obvios. Then you could use this in the next free radical mechanism you show).

Also explain the meaning and significance of free radicals in a footnote.

Ooh! It may also be relevant in passing to mention 'noise pollution'. Thus, with the development of air, road and rail travel, the world has become uncomfortably noisy. Noise pollution can be described as being any noise which causes stress and strain, or is painful to the ear.

"The internal combustion engine contributes to the increased concentrations of CO2 in the atmosphere"

Whilst sorting my study I just found some notes I jotted down from a video' which you might consider inserting: 'Everyday, one car produces the amount of CO2 which would require 6 trees to remove in photosynthesis (compare with a conventional power station which gives an amount of CO2 which would require thousands of trees to compensate.

I just had a thought. There is evidence that crude oil has a dual origin, both biogenic and abiogenic

(The abiogenic route is from inorganic sources by Fischer-Tropsch type of reactions).

Hence, to be pedantic:

'Motor fuel is obtained from crude oil produced by the decay of marine organisms'. >

Motor fuel is obtained from crude oil produced PREDOMINANTLY by the decay of marine organisms.

Returning to the PM10's:

In addition to the physical effects of particles entering the lung, these particles can act as vectors that carry chemical pollutants deep into the lung. Such pollutants include acids and metals such as iron, which can catalyse the production of highly reactive - and thus damaging- oxygen free-radicals.

n.b. There is data from the USA which shows a clear correlation between fine particle concentration and death rate (I've got this in graphical form, which I could possibly translate into a tabular form for inclusion in your Entry)

Well, things suddenly sped up! Nice to see you back, BigAl. I'll get to work, so.

TRiG_Ireland.

Here in Ireland, the emissions of cars are monitored as part of the National Car Test. If your car isn't clean, you won't be allowed drive it. Is this the case in other countries? If not, should it be?

Well, it's certainly not the case in the States!