Amazon’s ‘flying rivers’ dry up as drought takes hold


(Pic: Amazon/UN Photos)

(Pic: Amazon/UN Photos)

By Jan Rocha




Meteorologist Jose Marengo, a member of the Intergovernmental Panel on Climate Change, first coined the phrase “flying rivers” to describe these massive volumes of vapour that rise from the rainforest, travel west, and then − blocked by the Andes − turn south.


Alarming proportions

Deforestation all over Brazil has reached alarming proportions: 22% of the Amazon rainforest (an area larger than Portugal, Italy and Germany combined), 47% of the Cerrado in central Brazil, and 91.5% of the Atlantic forest that used to cover the entire length of the coastal area.

Latest figures from Deter, the Real Time Deforestation Detection System based on high frequency satellite images used by INPE, show that, after falling for two years, Amazon deforestation rose again by 10% between August 2013 and July 2014. The forest is being cleared for logging and farming.


As long ago as 2009, Antonio Nobre, one of Brazil’s leading climate scientists, warned that, without the “flying rivers”, the area that produces 70% of South America’s GNP would be desert.






“A big tree with a crown 20 metres across evaporates up to 300 litres a day, whereas one square metre of ocean evaporates exactly one square metre,” he said. “One square metre of forest can contain eight or 10 metres of leaves, so it evaporates eight or 10 times more than the ocean. This flying river, which rises into the atmosphere in the form of vapour, is bigger than the biggest river on the Earth.”



Nobre’s warning in 2009 was that if deforestation did not stop, there would be a catastrophe in five or six years time. Five years on, his words are now proving to be prophetic as São Paulo and all Brazil’s centre and southeast suffer their worst ever drought, with devastating effects on agriculture, energy and domestic water supplies. 

This article was produced by the Climate News Network


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