C. Heuzé, K.J. Heywood, D.P. Stevens and J.K. Ridley (2013), “Southern Ocean Bottom Water Characteristics in CMIP5 models“, Geophysical Research Letters, vol 40(7), pp 1409-1414, doi:10.1002/grl.50287
Assessment of the bottom water properties of 15 CMIP5 models over 1986-2005 against observations.
We found that CMIP5 models form dense water on the Antarctic shelf, but cannot export it to the open ocean.
Instead, models form their Antarctic Bottom Water by open ocean deep convection.
The models with the most accurate bottom properties are the ones with extensive deep convection in the Southern subpolar gyres.
Figure 1 of this publication is reproduced in the IPCC AR5, chapter 9 “Evaluation of Climate Models”