The Amazon is no longer the overlooked region of its constituent countries or the remote region of the world that it once seemed. Vast as it is, it is clearly not impervious to human impact. Indeed, in this era of globalization, the Amazon is vulnerable, economically and environmentally, to outside forces and can, in turn, affect other parts of South America and the world.
Some 25 years ago the Brazilian scientist Eneas Salati shattered the age-old paradigm that vegetation is the consequence of climate and, in reverse, has no effect on climate. He demonstrated elegantly that the Amazon literally generates half of its own rainfall within the basin. That led, of course, to concerns about the potential of deforestation to cause the hydrological cycle to degrade.