A recently published study by Lyman et al shows that although whole-ocean temperatures have been rising over the last half century, the temperature of the top 750 meters of ocean has actually dropped. This isn't as happy as it might sound, however. Were the temperature simply dropping for some ocean-internal reason, sea level should show a matching decline. As sea level is actually increasing, it's likely that the cooling seen in the upper levels is either incidental to or because of large-scale glacial and ice floe melting.
In other words, our warm ocean is, indeed, melting away our ice.
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