Of course, this is not the final word on ocean heat. Another analysis (Purkey & Johnson 2010) reconstructs ocean heat warming down to abyssal depths and find significant amounts of heat building up even at the bottom of the ocean.

Figure 4: Rate of ocean warming. Areas of warming are shaded in red and regions of cooling are shaded in blue with intensity scaled by the magnitude of the warming. The basins from south to north are the Southeast Pacific Basin, Chile Basin, Peru Basin, and Pacific Basin (Purkey & Johnson 2010).