Ch-Ch-Changes…

When scientists observed and analyzed four decades of hydrographic data, they found that tropical and subtropical Atlantic waters had become saltier over the course of 40 years (shown in top three globes) especially in the 1990s. Over the same 40-year period, deep waters became less salty in some key North Atlantic locations (bottom 3 globes), where salty, dense waters sink to drive the global ocean circulation system called the Ocean Conveyor. Scientists have been closely monitoring changes in the North Atlantic because it is a key turnaround point in the world’s ocean circulation system.
(Illustration by Ruth Curry and Jack Cook, Woods Hole Oceanographic Institution)