Earlier this year Rough Guide founder Mark Ellingham and I made a joint announcement in London on our concerns about the part that travel plays in the climate change equation. It prompted a headline in The Guardian: “Oops, we helped ruin the planet.”

Mark and I are good friends, but fierce business rivals, and we knew that making this announcement together would underline just how worried we are. The message that Mark and I were trying to put out was that we need to be aware of what we’re doing and travel responsibly. I wonder if the current craze in Europe for rushing to the other side of the continent for the weekend is sustainable?

Travelling not only contributes to causing the problem; it also makes you – if you just keep your eyes open – acutely aware of how severe the problem is and that abrupt changes in the earth’s climate have happened before.

The last couple of weeks I’ve been in China and south-east Asia where there’s plenty of everyday evidence of what we’re doing to the earth’s atmosphere. You hit the brown-grey pall that hangs over China hundreds of kilometres before you reach the coast. In Beijing or Shanghai you can sit in traffic jams which make Bangkok in the 80s (before they did something about it) look like toytown. Then in Kuala Lumpur I gazed out of my hotel window at an unrelenting grey haze from the unchecked burn-offs which have become an annual ritual in neighbouring Sumatra.

That’s today, but a visit to a rocky canyon in the Sahara Desert showed the huge impact climate change can have. Wadi In Galghien in southern Libya has a remarkable gallery of rock art notable for its remote location and the extraordinary quantity and quality of the carvings of giraffes, lions, elephants, rhinos, ostriches, cattle, antelope and even crocodiles: all animals which today are only found far to the south on the African continent. These rock carvings are not millions or even hundreds of thousands of years old. They date back only to 10,000 to 6,000 BC, a blink in time, but back to when the climate was clearly dramatically different.

Want a clear measure of how much travel hurts? One of the frightening comparisons from my own research is that a 747 carrying the Australian Grand Prix cars back to Europe after the race uses more fuel in the first half hour out of Melbourne than all the Formula One cars consume in practice and the race.

So what are we doing? All Lonely Planet travel is matched with carbon offset contributions to Climate Care. Is it enough? Like Darrell Wade of Intrepid in last Thursday’s Crikey I suspect it’s just the tip of the iceberg.