Because they care more about your grandchildren than you do. Or maybe even they strongly suspect that this is all a crock, but they're trying to cash in anyway

Sir Richard Branson, Ted Turner, Lord Stern & more than 100 leaders launch the world climate summit on Environmental Expert

Tomorrow, the most important and influential business, finance and government leaders in the climate change arena are coming together with more than 100 high-level speakers, and the largest coalition of financiers at the inaugural World Climate Summit, December 4-5, at The Ritz-Carlton, Cancun, Mexico, in parallel to the UNFCCC COP 16.
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The World Climate Summit is bringing more than 300 leading companies, financiers and government leaders to implement, scale and collaborate on bottom-up solutions to climate change to help reach regional and global 2020 targets. Participants will identify, initiate, and build out the business models, financing mechanisms, policies, projects, and practices needed for creating a global low-carbon economy.