Lewis has a private jet.

His lifestyle and employment has an impact on the planet far out of proportion to the average person.

By picking up some plastic off a beach he is raising the profile of this current issue, and has been praised for it.

Are many geographers also 'guilty' of teaching about the virtues of particular activities, but not backing it up with their own lifestyle or day-to-day actions?

A reminder of the importance of geographical thinking... Here's Peter Jackson on this sort of thing...

The power of geographical thinking from The Geographical Association on Vimeo.