Despite concern among scientists that politics have watered it down in distillation, the synthesis is expected to add urgency to next month's emissions meeting in Indonesia.
Sometimes warnings pack more punch when they come in a concentrated form – and at the right moment.
That's the hope United Nations officials have expressed after the weekend release of the last of four reports this year on global warming and options for trying to bring it under control.
The report reflects rising scientific confidence – and remaining uncertainties – in describing current and projected effects of global warming. That, plus the report's condensed size and terse talking points, virtually ensure it will play a key role in adding urgency to negotiations that begin on Dec. 3 in Nasu Dua, on the island of Bali in Indonesia.
The aim of next month's meeting is to gain consensus on a formal framework for reaching a new emissions-reduction pact over the next two years. A new pact would pick up where the 1997 Kyoto Protocol leaves off. Currently it only requires industrial countries to reduce their greenhouse-gas emissions by an average 5.5 percent below 1990 levels between 2008 and 2012.
Over the weekend, delegates from 140 nations meeting in Valencia, Spain, adopted the Intergovernmental Panel on Climate Change's (IPCC) "synthesis report." It's a thin volume distilled from three larger tomes the UN-sponsored group of scientists, economists, and other experts released earlier this year. It draws no new conclusions. But it does insist that some effects of global warming, such as sea-level rise, are inevitable and will continue for centuries, even if all heat-trapping greenhouse-gas emissions stopped tomorrow. Heading off the worst of the effects means moving aggressively to curb rising greenhouse gases, mainly carbon dioxide from burning fossil fuels, the report suggests.
The message "could not be simpler," says UN Secretary-General Ban Ki Moon. "Global, sweeping, concerted action is needed now; there is no time to waste."