I've read a few reports recently that one of the biggest polluters is shipping.

>>>Hi,
>>>Looks like they are broadly speaking comarable. This claims to show the general picture:
>>>http://www.grida.no/publications/other/ipcc%5Fsr/?src=/climate/ipcc/aviation/125.htm
>>>(but it doesn't appear to add weighting to the additional problems of CO2 at high altitude)
>>>One transatlantic round trip would probably churn out more CO2 per head than most people generate from a year of car use....
>>
>>What about the military planes? They are probably the least fuel efficient, they don't serve any useful purpose (other than to take the pilot out for a ride and bring him back), plus they serve a few very damaging purposes - like destruction of other goods or bads, which will then have to be remade, using more resources.
>
>I won't argue about the neccessity or otherwise of these flights but, from a practical poluting POV, I'd hazard that they form a miniscule proportion of total air traffic.
>
>>
>>I'm just deurinated for not being able to hear what I say several times a day. They fly over our heads, very low. Ooops, they must be ships, as they belong to the navy.
>
>FWIW I probably, at least for the UK, get more than my share of military air traffic - we're in a low-flying fast-jet training area (used by other EU counries as well as the UK) plus, with the SAS just down the road, we get low-flying rotary stuff as well. Not unknown for the windows to get rattled...
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>And there are probably several times a day when others don't want to hear what I'm saying anyway :-{
>
>Best,
>Viv