We’ve all read plenty about the IPCC this year as the U.N.-organized scientific body rolled out the tomes that constitute its fourth assessment of climate change research. This weekend the IPCC delivered its summation, and the results are both disturbing and heartening.

Disturbing because it reaffirms that the climate is changing and we are the unwitting drivers. Heartening because its synthesis affirms economic research showing that action against climate change is affordable. The IPCC estimates that aggressive action to stabilize atmospheric concentrations of greenhouse gases would, at worst, slim annual global GDP growth by 0.12%.

For a sharp précis of the report, Carbon-Nation recommends you to Joseph Romm on Climate Progress: “Absolute must-read report: IPCC says debate over, further delay fatal, action not costly”