Topic: | Re:Re:Re:Re:Re:Re:Re:Re:Re:Re:Air pollution in Putney | |
Posted by: | Andy Howard | |
Date/Time: | 28/02/14 17:39:00 |
Me neither. I'm just guessing here, but in the absence of air currents (of which in fact there are many), I'd expect the concentration of particulate pollutant to follow an inverse square law, a bit like light from a light source. So the effect of something 3000 feet away would be 10,000 less than something 30 feet away. So using Richard's figures, it would need 160 planes constantly overhead (ie 10,000/60), that is to say without the 40 second gaps to produce the same effect as 1 unregulated bus 30 feet away. Or very roughly, effect of 1 plane is much less than 1% of the effect of 1 bus. |