This blog was originally posted on the website Valuing Nature.

The climate change debate is forever mired in statistics (or what George Bush would call 'fuzzy math'). But it seems that in the last couple of days one number has really spoken: 150,000.

It took 150,000 coconuts to produce the biofuel to fill one fifth of one of the four fuel tanks on a Virgin Boeing 747 flight from London to Amsterdam. In other words, 5% of the fuel carried, on a flight of about the same distance as from London to Newquay.

I can't visualise a world that is 2'C hotter. But I think I can kind of imagine what a pile of 150,000 coconuts might look like, and it's quite big. The weird juxtaposition between the pictures of a jumbo jet on the tarmac at Heathrow, and the mound of coconuts beneath Latin American palm-trees that I see in my mind's eye, is potent reminder of the scale of the environmental implications of flying, conveyed in terms of something as humble, organic, and reminiscent of low-lying tropical paradises, as a hairy coconut.