Sea level anomalies affect the ocean circulation at abyssal depths.

Abyssal channels are the key points controlling bottom circulation of the World Ocean. They provide meridional transport of the coldest Antarctic Bottom Water between deep-water basins influencing the meridional overturning circulation and the climate on a global scale. Here we show that the synoptic variability of deep-water flows including blocking abyssal currents between deep ocean basins is related to sea level anomalies observed over the channels. Our results demonstrate that processes at the ocean surface have a more significant connection with the bottom circulation than it was considered earlier. This study opens a discussion of the importance of mesoscale eddies and air-sea interactions on water exchange between abyssal basins, meridional heat transport in the ocean, and possible responses of the ocean to the observed sea level rise in a changing climate.