This, of course, has implications for what ocean life can survive and where, for currents (like the Gulf Stream) and for sea ice.
Sea-surface temperatures worldwide have been the hottest on record over the last three months, the National Oceanic and Atmospheric Administration said Wednesday.
The report is based on data back to 1880.
Climate change has been raising the planet's average temperature steadily in recent decades. All of the 10 hottest years on record have occurred since 1997.
And yet, the world's people (for the most part) just go on about their business with little to no conern and do not experience this as the truly urgent issue it really is.