In the face of a staggering quantity of evidence to the contrary, politicians, journalists and science pundits continue to insist that global climate change isn't real. But this June there's a new opportunity for the world to act to save our planet.
In a few weeks, world leaders will meet in Brazil for the Rio+20 summit. Sometimes it feels like the facts won't convince climate change sceptics – so maybe graffiti can. Guerrilla street artist Banksy authored this gem in 2009 during the hugely disappointing Copenhagen climate summit. As global delegations head to Rio, a city severely threatened by rising tides, the world needs leaders – artists, academics, policymakers, us – to speak out and act. Here's how Banksy took the initiative:
Take action: Use the Guardian's tool to measure your own carbon footprint.