A massive drought in the Amazon in the late summer, is still having an impact 3 months later with scientists debating the long term effects.
The source of the drought conditions are believed to have been generated by warmer surface temperatures in the Atlantic Ocean, just to the north of the equator.The effect of this is to pull the trade winds and their moisture content away from the region, causing less precipitation in western and central Amazon.
To make matters worse, the subsequent reduction in cloud cover and rainfall over the rainforest has created higher land surface temperatures causing increasingly dry conditions and the likelihood of more forest fires than usual.
One of the Amazon’s main tributaries – the Rio Negro – is experiencing its lowest ever water levels which has made fishing and river transport very difficult. Even the river barges normally hauling soy products out of the Amazon have apparently been grounded. Human populations, too, have suffered negative impacts, not least due to smoke inhalation from widespread forest fires.
The drought is thought to be similar in size to that experienced by the Brazilian Amazon in 2005, an event that was described at the time as a once in a century phenomenon.
Dr. Luis Aragão – a remote sensing expert from the University of Exeter – claims this time the drought is less intense, though arguably broader in scope.
Scientists are still debating exactly what the impact of this year’s Amazon drought will be on the forest’s overall loss of biomass and ability to store and capture CO². While ground data show increased tree deaths, some have argued that the forest is more resilient to drought than previously thought and that leaf loss may lead to increased regeneration.
“I imagine that this second Amazonian drought in just 5 years will cause significant concern in the UN Climate Change Summit Meeting this week in Cancun,” suggests Matthew Owen, Director of UK NGO Cool Earth. “Hopefully, it will spur the decision-makers into action and positive multi-lateral agreements.”