Carbon dioxide at the outer edge of the habitable zone

Atmospheric constraints for the CO₂ partial pressure on terrestrial planets near the outer edge of the habitable zone
http://arxiv.org/abs/1211.4367

Various effects of stellar insolation, etc.

One potentially interesting consequence:

Quote :

As has been shown above (Fig. 3), for planets orbiting within the HZ of K-G-F stars there is a region of liquid surface CO₂ combined with surface temperatures above 273 K, i.e. liquid surface H₂O. This means that it is possible to form H₂O-CO₂ oceans.