Scientists analyzing measurements taken in the deep ocean around the globe over the past two decades find a warming trend that contributes to sea level rise, especially around Antarctica. Greenhouse gases in the atmosphere, such as carbon dioxide, cause heating of the Earth. Over the past few decades, at least 80 percent of this heat energy has gone into the ocean, warming it in the process.
Everyone looks at air temperatures, since we live on land, but the ocean has been picking up most of the increasing heat being trapped on the planet. Luckily for us. If that heat had stayed in the atmosphere, it would be rising at over 5 °F a decade.
But this increased heat, especially in the deep ocean, not only raises sea level by thermal expansion but also has the real potential for disrupting the underwater rivers that move cold, deep water to the surface, and warm, shallow water to the deep.
Warmer deep waters means that it can take a long time to blow off the heat effects in the atmosphere. The human race may have to start learning pretty quick how to adapt to a rapidly changing world.