This is not an attempt to denigrate pachyderms. The eye-catching figure is the result of a study presented by the Lausanne-based International Institute for Sport Science and Technology who this week hosted a seminar of sustainable sports events.
The researchers observed that while the actual cycling was effectively near to zero carbon, the entourage of support vehicles, motorbike escorts and three helicopters used over the four days soon totted up to an impressive total of greenhouse gas emissions.
There is always more to events than meets the eye. We know from our own work here at London 2012 that there are numerous potential sources of environmental impact in the materials, equipment and services that go to put on major events.
But the good thing is that more and more people are nowadays looking into these issues and coming up with imaginative solutions. Many of these have applications beyond the particular events in question, so in this way sport can be a driver for positive change.
At the seminar we ran an exercise asking delegates to propose improvements to their own events by using London 2012's Sustainable Event guidelines. It was encouraging to see examples from sailing, cycling, athletics and football at many different levels from local events to World Cups all seeking more sustainable solutions.
We also learnt of energy saving initiatives used in staging the Superbowl finals, how offcuts from sail cloth may be used to make bags and other goods rather than being thrown to waste and how some merchandise products are being tagged so they can be traced all along the supply chain from original cotton growers to finished articles.