Amazon's record drought caused by climate change

The Amazon rainforest's record drought in at least half a century caused by climate change, according to a new study. Often described as the "lungs of the planet", the Amazon plays a key role in removing warming carbon dioxide from the atmosphere.

But rapid deforestation has left it more vulnerable to weather extremes.

While droughts in the Amazon are not uncommon, last year's event was "exceptional", the researchers say.

In October, the Rio Negro - one of the world's largest rivers - reached its lowest recorded level near Manaus in Brazil, surpassing marks going back over 100 years. As well as being a buffer against climate change, the Amazon is a rich source of biodiversity, containing around 10% of the world's species - with many more yet to be discovered.

The drought has disrupted ecosystems and has directly impacted millions of people who rely on rivers for transport, food and income, with the most vulnerable hit hardest.

Climate change has made a drought of this severity around 30 times more likely, according to the researchers, and one is now expected to happen every 50 years under current conditions. "This really is something quite exceptional," says Dr Ben Clarke, a researcher with the World Weather Attribution group.