If anyone ever thought climate sciences were anything but complex, they obviously weren’t looking hard enough. Recent research from prominent UK and Brazilian climate scientists have found a link between reducing sulphur dioxide emissions from burning coal, and the increase in sea surface temperatures in the tropical north Atlantic, that heightens the risk of drought in the Amazon rainforest.
The Amazon is without a doubt one of the planet’s most valuable and important ecological resources; and not for logging. The rainforest contains approximately one tenth of the total carbon stored in land ecosystems, and recycles much of the rain that falls upon its leafy canopy.
Thus, any major change to its vegetation has massive implications for the global climate system.
During the 70’s and 80’s, sulphate aerosol particles being emitted from the burning of coal have contributed to partly reducing global warming in the northern hemisphere, by reflecting sunlight and making clouds brighter. As a result, this pollution has helped to limit the warming in the tropical north Atlantic.
This has kept the Amazon wetter, than had the global warming been allowed to increase the temperature in that part of the world as well. Chris Huntingford of CEH, one of the studies co-authors, explains: “Reduced sulphur emissions in North America and Europe will see tropical rain-bands move northwards as the north Atlantic warms, resulting in a sharp increase in the risk of Amazonian drought”.
A team from the University of Exeter, Centre for Ecology and Hydrology, Met Office Hadley Centre and Brazilian National Institute for Space Studies used a climate carbon model at the Met Office Hadley Center to simulate the impacts of 21st century climate change on the Amazon. They then compared data from the 2005 drought – which had caused massive devastation to the Amazon basin – and found that by 2025, a drought on this scale could happen every other year, and by 2060 a drought could occur in nine out of every ten years.
There are a number of factors playing havoc with the Amazon, as co-Author Dr Carlos Nobre of the Brazilian Institute for Space Research explains: “Global warming, deforestation and increased forest fires are all acting in synergy to reduce the resilience of the Amazonian forests”.
While another of the co-authors, Dr Matthew Collins of the Met Office Hadley Centre, summed up the future: “The rainforest is under many pressures. Direct deforestation is the most obvious immediate threat, but climate change is also a big issue for Amazonia. We have to deal with both if we want to safeguard the forest.”
Image Courtesy of markg6 via Flickr
Source – Press Release