From the atmosphere to the abyss in the Southern Ocean- How the wind could be influencing the abyssal circulation

Recent observations of the warming of the abyssal layer of the world’s ocean raise the question of what controls the variability of Antarctic Bottom Water (AABW), the water mass filling the deepest parts of much of the oceanic basins. With co-workers at the National Oceanography Centre Southampton and the British Antarctic Survey, I have been trying to understand the relationship between atmospheric forcing, the local oceanic circulation and the properties of the Antarctic Bottom Water exported out of the Weddell Sea, the main formation region of this water mass. We found that an increase in the wind speed over the northern Weddell Sea result in the trapping of the coldest, most dense water in the Weddell Sea, creating, only a few months later, an apparent warming of the bottom water downstream. Could this be an indication of the influence of humanity on the circulation and properties of the abyssal ocean – an effect that could increase in the future?