I think the part about differential warming of different layers of the ocean to be particularly clear and useful. (realclimate.org)
NH - SH differential warming and TCR «Isaac Held's Blog.» (skepticalscience.com)
The diagnostics, which are used to compare model - simulated and observed changes, are often simple temperature indices such as the global mean surface temperature and ocean mean warming (Knutti et al., 2002, 2003) or the differential warming between the SH and NH (together with the global mean; Andronova and Schlesinger, 2001). (ipcc.ch)