It's not good news:
Will Amazon drought worsen in 2007?
In the Southern Amazon, a region that has suffered the brunt of deforestation due to clearing for cattle pasture and agriculture, April or May mark the beginning of the dry season. Rains usually return in September or October, though in recent years, dry seasons have been prolonged, with increasingly severe impacts on the forest ecosystem. In 2005 and 2006 the Amazon experienced the worst droughts on record as thousands of square kilometers of land burned for months on end, releasing more than 100 million metric tons of carbon into the atmosphere. As rivers dried up, remote communities were isolated while commerce slowed to a standstill.
2007 is shaping up to be a similar year with meteorologists forecasting conditions akin to those seen in 2005: warming in the tropical North Atlantic (the same conditions that influence hurricane formation in the Caribbean and East Coast of the United States). Another year of drought is of great concern to researchers studying the Amazon ecosystem. Field studies by the Massachusetts-based Woods Hole Research Center suggest that Amazon forest ecosystems may not withstand more than two consecutive years of drought without starting to break down.
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Simulations by scientists from Woods Hole and other institutions suggest that 40 percent of the Amazon could be lost by 2050. Climate change, which may increase temperatures in the basin by as much as five degrees Celsius (eight degrees F), could exacerbate the loss.
"The threat of a “permanent El Niño” is therefore to be taken very seriously," said Dr. Philip M. Fearnside of the National Institute for Research in the Amazon (INPA) in an interview with mongabay.com last year. "Again, it depends on how seriously society takes the problem to be. If fossil-fuel combustion and deforestation are reduced to reflect the importance of the problem, then the worst could be avoided. If this does not happen, the danger of a “runaway greenhouse” escaping from human control becomes much greater. Disintegration of the Amazon forest, with release of the carbon stocks in the biomass and soil, would be a significant factor in pushing us into a runaway greenhouse."