This is more what worries me as a bigger picture. I am unclear what triggerd the climate changes in north Africa, causing the Sahara Dessert Where I believe 2000 years ago there were grain fields? However climate change on a major portion of a continent mus surely affect wider weather systems? an even more frightening prospect than loacal ecological disasters to my mind. On Wed, Dec 28, 2011 at 3:47 AM, lou jost <loujost@yahoo.com> wrote: > The most disturbing thing about the Amazon basin is its climatic > instability. Recent studies suggest that if mean temperature goes up just a > little, or precipitation declines, the climate will pass a threshold and > the forest will revert permanently to savannah, with no hope of returning > forest. Because deforestation increases temp and decreases rainfall, the > area is headed towards this threshold at an ever-accelerating rate. The > future does not look good. >