View of a deforested area in the Amazon rain forest in northern Brazil in 2005. Worry spots include the Greenland icesheet, the Amazonian forest as well as Siberia, where billions of tonnes of natural greenhouse gas could be freed from melting permafrost. (AFP Photo/Antonio Scorza)

New vegetation grows under a burnt trunk in the Amazon rain forest, Brazil. The upcoming Rio conference on sustainable development must yield a commitment to manage the world economy in a way that respects the environment and fights poverty, a Brazilian official says. (AFP Photo/Antonio Scorza)