“Limits… for natural systems would largely be exceeded throughout the world”

If global mean temperature increases to 4 °C (7.2 °F) above preindustrial levels, the limits for human adaptation are likely to be exceeded in many parts of the world, while the limits of adaptation for natural systems would largely be exceeded throughout the world. Hence, the ecosystem services upon which human livelihoods depend would not be preserved.

source: http://en.wikipedia.org/wiki/Global_warming

Also cf:
http://rsta.royalsocietypublishing.org/content/369/1934/217.full