The Conservative Take Away

 The conservative take away from IPCC AR5 is the baseline model RCP8.5, and the projected impact. That is the "conservative" model, since it relies only on past and current observable human behavior, not some assumption of a sudden, radical change in that behavior.

So if you work on or are interested in adaptation matters, you may want to read up on the Paleocene–Eocene Thermal Maximum (PETM) which is similar (except for rate, ours is much faster) RCP8.5.