Climate change in the Amazon basin

Scientific American has an interesting review of a report in Nature describing climate changes in the Amazon area resulting from human activity. Clearly there could be similar effects here in Guyana, if the deforested areas here get large enough, and the climate changes in the central Amazon could also indirectly affect the weather in southern Guyana which is on the edge of the Amazon basin.
From the article:

"The dry season is growing longer in areas where humans have been clearing the trees... Multiyear and more frequent severe droughts, like those in 2005 and 2010, are killing trees that humans don't cut down as well as increasing the risks of more common fires (both man-made and otherwise)."

"The trees are also growing fast — faster than expected for a "mature" rainforest..."

"On the whole, cutting down trees so that the Amazon covers only roughly 80 percent of the land it once did seems to have tipped the rainforest from being a sink for global CO2 emissions to a net source, although this calculation remains highly uncertain, the scientists noted."