Having trouble getting yer "mind" around the concept that the ocean is a 3 dimensional heat sink?
The oceans are the flywheel of the climate system. As atmospheric concentrations of greenhouse gases increase, the Earth system is warming, and over 90 percent of that increase in heat goes into the ocean. Knowing how much heat the ocean absorbs is vital to understanding sea level rise (the oceans expand as they warm), and predicting how much, and how fast, the atmosphere will warm. Most estimates of ocean warming have been limited to the upper 700 meters of water, owing to the limited availability of ocean-temperature data below that depth. Since about the turn of the millennium, the Argo array, an international system of robotic profiling floats, has massively increased ocean sampling to 2,000 meters, and allowed scientists to show conclusively that ocean warming extends below 700 meters.
However, the ocean is also warming near the bottom, in the coldest waters of the abyssal zones. Oceanographers measure the abyssal ocean to depths of 6,000 meters by lowering accurate recording thermometers and other instruments to the ocean floor on long cables from research vessels. During the 1980s and 1990s, an international program called the World Ocean Circulation Experiment collected thousands of such profiles around the globe.
During the 2000s, we and our fellow oceanographers returned and re-measured ocean properties at many of those sites. We detected a consistent warming signal in the abyssal ocean around the globe. The strongest warming is occurring in the Southern Ocean, around Antarctica, at a rate of approximately 0.03 degrees Celsius per decade. [ Warming in Deep Southern Ocean Linked to Sea-Level Rise]
Further north, abyssal ocean waters are also warming, but at a rate of about one tenth of what we see in the deep Southern Ocean. Even though the temperature increases are small, because they are spread over huge ocean basins in layers a few kilometers thick, they quickly add up.
The warming in the deep Southern Ocean alone accounts for 34 terawatts of warming, roughly equivalent to the continuous operation of three 1,500-watt electric teakettles for each of the 7 billion people on the planet. This warming could offset some of a recently reported slowdown in the upper ocean's warming rate.
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