We placed a card in a place it couldn't be missed: on taximeters. The card placed a ‘°C’ symbol right next to the fare. So the further you travelled in a taxi, and the further the fare went up, the greater the rise in ‘temperature’ and the higher the real environmental cost of your journey.

The campaign was a hit on social networks. Thousands of posts about the card were shared on Facebook and Twitter in the first week, and the Friends of the Earth website saw a surge in visitors.