The Amazon Rainforest

Forests cover 30% of Earth's total land area. They are an important part of the climate system in several respects. First, wood stores carbon: all green plants obtain the carbon in their tissues by extracting CO2 from the air, breaking out the carbon, and releasing the oxygen. Trees, the largest plants, store the most carbon, sequestering it in persistent woody tissues that can keep carbon out of the atmosphere for centuries or millennia (4,000 years, in the case of certain bristlecone pines). Second, large amounts of carbon are stored in forest soils, as dead branches, leaves, needles, trunks, and other tree parts accumulate and partly decay. By keeping CO2 out of the atmosphere, forests mitigate climate change (make it less severe). Because the vast majority of the Amazon rainforest has not been catalogued, the exact number of species in the Amazon rainforest is unknown. The World Bank estimates that 10% of all the world's species live in the Brazilian Amazon and most of them are found only in that area. Headlines around the world have clearly indicated that the problem of deforestation in the Amazon and elsewhere has been getting worse in the past decade. (Stone 50-57)

Third, trees are dark and so decrease the planet's surface albedo, especially in snowy northern regions, which tends to increase global warming. Fourth, deforestation to clear land for agriculture and to extract lumber and fuel-wood, which has been particularly severe in tropical regions for decades, releases carbon from forest trees and soils, enhancing global climate change. Throughout the 1990s, tropical deforestation was responsible for 20-30% of global anthropogenic (human-caused) greenhouse-gas emissions. Deforestation has slowed only slightly in the early 2000s. Planting and conservation of forests is a primary goal of schemes to mitigate global climate change, such as the Kyoto Protocol.

Location

The Amazonian Tropical Rainforest is an area of the South American continent that covers parts of five countries. Included under this umbrella are parts of Brazil, Venezuela, Colombia, Ecuador, and Peru. Hence it is not inconceivable that changing the fundamental type of ecosystem of an area this large will have potentially global consequences. The area defined as the Amazonian rainforest covers 914 million acres according to World Bank and World Wildlife Fund statistics. (Anderson 1191-1205)

The rainforest, because of its sheer size, is a self sustaining climate system. The rainforest creates its own weather patterns. It's not called the rainforest for nothing. Water that evaporates from one part of the rainforest eventually triggers rain on another part of the rainforest. If a large part of the periphery of the rainforest is cut down, that area dries up, becomes overgrown with brush and weeds, and ceases to be part of the system. And because the entire system is interconnected, there is a critical mass needed for the system to continue to be viable. If less than the critical mass remains, the climate patterns will probably shift enough to eliminate most of the rainfall for the rest of the system, thus putting the entire rainforest ...