Tree loss accounts for at least 20% of global carbon emissions. What would help cap that output is an international market — similar to that in the power industry or manufacturing — that allows tropical nations to preserve their rainforests in exchange for selling the carbon emissions contained within them. That doesn't exist, in part because major tropical countries like Brazil and Indonesia have been reluctant to accept international carbon finance, for fear of losing control over their natural resources. But Indonesia — the world's third biggest carbon emitter, thanks chiefly to its high deforestation rates — now seems ready to open up. At California Gov. Arnold Schwarzenegger's climate summit in November, Indonesian officials announced their government would set up a regulatory framework for carbon forestry programs, and signed an agreement with California to help shepherd those projects. Translation: Indonesia appears ready to help wealthy California help Indonesia preserve its rapidly dwindling rainforests — and the climate will benefit.