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.
Now we know that when the moisture-laden, westward-moving Amazonian air masses hit the high wall of the Andes, a significant fraction of the moisture is deflected south and provides rain to southern Brazil and northern Argentina. So now we understand that even if the Amazon as a forest -- and as probably the greatest repository of biological diversity on Earth -- is not viewed as important by some in southern Brazil, the Amazon as a rain machine is crucial to agribusiness and the production of hydropower.
We also know that the Amazon can be affected climatically by things that occur beyond Amazonia. In 1997 El Niño (which 30 years before had been considered a local phenomenon off the coast of Peru) showed that it not only can reach across the Pacific to cause drought and fires in Southeast Asia but that it also can reach across the Andes and cause drought on the eastern side of the continent, including in northeast Brazil and the Amazon.
In 2005 the Amazon suffered the most severe drought ever recorded. It was linked to changes in the Atlantic circulation and was completely independent of El Niño. This is probably a preview of what climate change could bring. The Hadley Center's global-climate model predicts drought and Amazon dieback if greenhouse-gas concentrations increase to double pre-industrial levels -- around 560 parts per million (ppm). (We are currently at 385 ppm.)
Recent analysis indicates that world tropical deforestation contributes more than 20 percent annually to the net increase of CO2 globally. Brazil is one of the largest contributors to that, almost entirely due to Amazon deforestation and burning. Of course it makes no sense for the Amazon to be contributing in this way to its own risk from climate change.
The Amazon River system is rich in fish diversity -- 3,500 species, more than in the entire North Atlantic -- some of which are very important for food, and some valued by the ornamental-fish trade. More than one fishery is showing signs of serious overfishing. Deforestation in headwaters can create serious problems downstream, and some fish species literally swim the length of the river system in the course of their lives. All of these links need to be integrated into a policy for a sustainable future for Amazonia, and that can only be achieved through policies that connect from the basin to the national level, and, ultimately, to the global level. The Amazon has to be managed as a system; anything short of that is bound to fail. The Amazon Cooperation Treaty (ACT) is a very useful instrument in this regard, especially now that it has a permanent secretariat in Brasília.
In the meantime, however, deforestation continues in almost all the Amazon countries. At the moment, Brazil, which does a far better job of measuring Amazon deforestation than the other countries, has made some serious progress in reducing the rate. Nonetheless, Amazon deforestation is getting perilously close to the tipping point where the hydrological cycle will irreversibly degrade. But the exact tipping point is unknown, and defining it is, in fact, a much more complicated problem than it might seem, depending as it does on the impact of deforestation and different kinds of replacement vegetation (for instance, soybeans vs. second growth) in different parts of the basin. It would be tragic to discover the tipping point by triggering it. We have reached the point where deforestation should be stopped, not slowed.
At the same time, any approach to manage the Amazon sustainably must take into account economic forces both within and without the basin. In parts of the Amazon, oil and gas concessions literally cover the map like quilt work. So too do forest concessions. Global interest in commodities like soybeans and timber bring market forces to bear, and not necessarily in good ways. Soybeans represent a threat to biodiversity and the hydrological cycle. Palm oil, while of little or no biodiversity value, at least is a tree crop and can contribute to the hydrological cycle. In the state of Pará some of the degraded land could be restored to productivity as palm plantations, although care should be taken to balance it with restoration of natural forest. There are real advantages to having palm plantations embedded in a matrix of natural forest.
Similarly, while sugarcane does not grow well in the Amazon, it can expand northward into the cerrado region of Brazil. Were it to do so, it could displace cattle ranching farther into the Amazon.
On the plus side of the agenda has been an impressive burst of activity in the creation of protected areas in virtually all of the Amazon nations. A new generation of political leaders has emerged at least in some places, including the Brazilian states Amazonas (Governor Eduardo Braga's government) and Acre (former Governor Jorge Viana), who embrace sustainability and see the future as dependent on the forest.
Ultimately, it is difficult to see a secure path to a sustainable future for the Amazon without considerably more resources from outside the region. That almost inevitably means resources from outside the Amazon nations, but global involvement needs to be perceived as supportive of national and regional actions, not as "internationalization." The Pilot Program to Conserve the Brazilian Rain Forest (PPG7) was and is just such an effort. Braga's government sees this, for example, as payment for environmental services such as carbon sequestration, rainfall generation, and maintenance of genetic resources. Probably the most promising way to achieve this would be to include "avoided deforestation" as part of carbon trading under the Clean Development Mechanism of the Kyoto Protocol, but there are probably other imaginative ways as well. What is critical is for a portion of the funds to end up in direct support of local communities so they can have a reasonable quality of life without destroying the forest.
In the end, the Amazon poses a challenge for each of the Amazonian nations, as well as for the entire planet. First, those nations have to work together to maintain the integrity of the Amazon as a system; they need the benefit of fairly uniform approaches. Second, because of the global importance of Amazonia, the rest of the world will need to pool financial and intellectual resources to foster Amazon sustainability. As complex as that is, and so easily clouded by concerns about biopiracy and sovereignty, there is no reason the obstacles can't be overcome. Indeed the Amazon itself provides every reason to do so.