A mighty river is flowing out of the Amazon rainforest, and it’s not the one you’re thinking of. In the first kilometre above the forest canopy, a “flying river” is transporting moisture evaporated from Amazonian trees southwards along the Andes mountains towards Rio Grande do Sul, the southernmost state in Brazil.
Almost the entire state – an area larger than the UK – is currently affected by unprecedented floods. The flying river has acted like a firehose, fuelling five months of rainfall in just two weeks, further enhanced by a strong jetstream located in just the wrong position above the region. And, based on future projections of climate change, this situation will likely get worse as the temperature rises.
Since the beginning of May, those massive floods in Rio Grande do Sul have made world headlines. In the state’s capital, Porto Alegre, the Guaíba river is more than five metres above its normal level, breaking a record set in 1941. The death toll is 149 and growing, with 108 still missing. The floods have displaced more than 600,000 people and directly or indirectly affected more than 2 million, in 446 of the 497 municipalities in the state.