Seriously? "assuage the conciense of the green lobby" at an airshow? Now I've heard everything.
How about, for starters, aviation only accounts for 3-5% of the total carbon emissions worldwide, so it hardly earns all the flak it gets in the press. And that's commercial jet transport. General aviation like us are negligible in comparison to even that small 3-5%! It's just an easy political target. If any of the green lobby attend said airshow, unless they walk to it, they've got no right to have their concienses assuaged.
But, if we're going to take this seriously, consider the following:
1. It's purely a daytime activity, requiring no power for massive banks of lights like a night rugby world cup game (for example)
2. Most attendents will be local, meaning the overall carbon footprint for the event will actually be quite small as there will be very little travelling per person attending
3. The organisers could do some research into what species of flora and fauna live on the airfield, making the airfield itself a green preservation environment BECAUSE of, not in spite of, it's use as an airfield. How many of said species live on the nearest housing/industrial estates?
4. How about other contractors (caters, loos, etc). Are they all local, not only meaning travel issues but support of local businesses?
There's probably some other stuff I could think of over time. I was the Ground Director of Mildenhall's Air Fete for two years (average attendence, 300,000 over two days). Give me a shout and I can give you a few other things to think about.
Cheers,
Pitts2112