Well, yes and no. The whole issue is so complicated. But the reason I ask is that a well know climate change activist who questioned my daughter’s school trip (by plane) recently told me about plans to fly to Mexico for the next round of climate talks. “Surely some flights are justified?” s/he asked.

How am I supposed to pass judgement? Surely the “planet” doesn’t care if your flight is for work, play or environmental justice? What really matters is that we all fly less and that we lobby for suitable alternatives (whether that’s web conferencing, trains or whatever).  A quick poll of my neighbours reveals that 8 out of ten of us haven’t flown at all in the past five years (either because of lack of money or inclination or both),  I’ve been to more than a dozen European cities by train or car and had amazing adventures, but I would certainly never make a “no fly” commitment.

So, forgive me for asking, but what do you think? Are some flights more justifiable than others? Is my once every ten year flight to visit familiy in the States more sinful than an academic flying across the Atlantic  several times a year to give a 20 minute presentation at a climate change conference  or an activist flying to Copenhagen and then being denied access to the talks because of an oversubscription of delegates then catching  a return flight home to get back to work?

I doubt there’s a definitive answer. But, if you want to know the carbon cost of your travel take a look at RouteRank, a new website which compares CO2 emissions from various methods of transport and for goodness sake, remember that offsetting does not “neutralise” your carbon and that yes, a tree might “reabsorb” the CO2 emitted by your flight – but by the time it’s done so, the real human damage has already been done. On the face of it, sometimes flying really is Plane Stupid?