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As vast tracts of rain forest are cleared, Brazil has become the world's fourth-largest producer of the greenhouse gases that cause global warming, after the United States , China and Indonesia , according to the most recent data from the U.S.-based World Resources Institute. And while about three-quarters of the greenhouse gases emitted around the world come from power plants, transportation and industrial activity, more than 70 percent of Brazil's emissions comes from deforestation.
Burning and cutting the forest releases hundreds of millions of tons of carbon dioxide, methane and other gases that the vegetation had trapped. Those gases collect in the atmosphere, prevent heat from escaping and help raise the Earth's temperature. Keeping greenhouse gases out of the atmosphere has become crucial to saving the planet from catastrophic climate change, scientists say. However, stopping the destruction of the vast Amazon rain forest means confronting the region's lawlessness and persuading Brazilians such as Pereira to leave the forest alone.
" Brazil has a huge amount of forest that's still there, and that means Brazil has a much greater role in terms of future deforestation," said Philip Fearnside , a research professor at Brazil's National Institute for Amazon Research . "Any changes that happen here have great influence on whether the Earth gets warmer."
The 1.5-million-square-mile Brazilian Amazon, larger than the entire nation of India , contains more than 40 percent of the world's rain forests, and about a fifth of it already has disappeared, mostly in an "arc of deforestation" along the forest's southern and eastern edges. Every year, another chunk of forest the size of Connecticut or larger disappears as farmers, illegal loggers and others clear jungle, mostly without government approval. Violent clashes over land are common, as are murders of environmentalists.
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http://news.yahoo.com/s/mcclatchy/20070910bcbrazildeforest_attn_national_foreign_editors_ytop