“Warming of the climate system is unequivocal,” warned the Nobel Prize-winning Intergovernmental Panel on Climate Change in its hardest-hitting report yet, released on Saturday. Delegates from more than 140 countries came to agreement on the document, which summarizes three previous reports and warns of the grave dangers posed by climate change. The new report is intended to be a guide for policymakers — particularly the ones who’ll be meeting next month in Bali, Indonesia, to begin hammering out a new treaty to pick up where the Kyoto Protocol leaves off. “Today the world’s scientists have spoken, clearly and in one voice,” said U.N. Secretary General Ban Ki-moon. “In Bali, I expect the world’s policymakers to do the same.” Scientists reportedly managed to fend off efforts by U.S. representatives and others to weaken the report — and yet many experts say the final version still doesn’t capture how bad the situation really is. “The IPCC is a five-year process and the IPCC is struggling to keep up with the data,” said Hans Verolme of WWF. “And the new science is saying: ‘You thought it was bad? No, it’s worse.’”