Decadal shifts in ocean basin mass detected in satellite observations



Global warming is changing the sea level on a global scale by melting ice and snow, but sea level variations on smaller scales are linked to change in ocean circulation. From 2003 to 2012, observations show that some of the world's ocean basins have lost mass while others have grown. For instance, changing circulation patterns have caused the North Pacific to rise by an extra 1.9 centimeters per decade, irrespective of sea level rise caused by water additions from melting ice or groundwater depletion. Parts of the South Atlantic, the Arctic, and the southern Indian Ocean are also rising, while regions of the North Atlantic, South Pacific, and northern Indian Ocean are falling, according to an analysis by Johnson and Chambers of the most recent observations made by NASA's Gravity Recovery and Climate Experiment (GRACE) satellites.