Climate change helped cause Brexit, says Al Gore

Mr Gore, speaking at an event in which he previewed a sequel to his landmark 2006 documentary, An Inconvenient Truth, said the “principal” cause of the Syrian Civil War had been the worst drought in 900 years, which forced 1.5 million people to move from the countryside to the cities.

There they met a similar number of Iraqis who had fled the conflict in their homeland, creating powder keg conditions that Syrian government officials privately feared would explode.

The resulting war brought more refugees into Europe, causing political instability and helping convince some in the UK to vote to leave the European Union.

One of the most controversial Leave campaign posters showed a queue of refugees stretching into the distance with the caption “Breaking point: The EU has failed us all”. The then-Chancellor, George Osborne, described the poster as “disgusting and vile” and, like others who explicitly compared it to Nazi propaganda, said it had “echoes of literature used in the 1930s”.

Mr Gore, whose new film An Inconvenient Sequel: Truth to Poweris due out in the UK in August, told an audience at the Advertising Week Europe event in London: “This collision between the power of industrial civilisation and the surprising fragility of the Earth’s ecosystem now poses a great danger that could even threaten the future of human civilisation itself.

“One of the lines of investigation [scientists] have been pursuing has led them to the conclusion that significant areas of the Middle East and North Africa are in danger of becoming uninhabitable.

“And, just a taste of this, to link it to some of the events that the UK and European Union are going through – think for a moment about what happened in Syria. 

“Before the gates of hell opened in Syria, what happened was a climate-related extreme drought.

“From 2006 to 2010, 60 per cent of the farms in Syria were destroyed… and 80 per cent of the livestock were killed. The drought in the eastern Mediterranean is the worst ever on record – the records only go back 900 years, but it’s historic.

“And 1.5 million climate refugees were driven into the cities in Syria, where they collided with refugees from the Iraq War.

“Wikileaks revealed the internal conversations in the Syrian government where they were saying to one another ‘we can’t handle this, there’s going to be a social explosion’. There are other causes of the Syrian civil war, but this was the principal one.”