But in many critical areas, IPCC scientists say the world is flying blind into the storm. By the time they publish their next report — at the end of this decade — there will be more clarity about where global temperatures will peak. Green policies will have triggered social and economic transformation, with major benefits — and major upheaval. That means there are still far too many unknowns to say with certainty how and when the most devastating impacts will hit. “Generally, science is still lagging policy,” said Piers Forster, an IPCC author and director of the Priestley International Centre for Climate at the University of Leeds. - Politico