so we can't all save as much carbon emission as we'd like - maybe we have gas guzzling cars and planes - so how could we reduce our feetprint?
one way would be to turn off lights - this would obviously be quite dangerous, but it would certainly save fuel - but (a bit like going round plugging in lots of plugs to stop electricity leaks, but then unplugging all the phone chargers to stop wasting electricity) it is "in the noise" (as david mackay's excellent book explains so clearly)
A better solution (as outlined in aforementioned book) would be to stop using brakes - lots of stopping and starting is what messes up your engine efficiency (and requires you to push all that air out the way, especially when doing take offs, or pullin away with both turbos on the 5.8 liter engine spinin on max) - so we just need to drive (or fly) at crusin speed all the time
what about intersections? No problemo - all that happens is after a few days of mayhem, darwin will eliminate all the drivers and pilots with poor timeing, and then the total number of vehicles on the road (or in the air) will be far less anyhow, so then we will have succeeded globally and locally in optimising the greenicity of the world's car and air transport networks....
simple, doncha see?