The scientists calculated that irrigation and the subsequent runoff into the oceans accounted for 6% of the total rise in sea levels for 1900-2008. Since 1950, groundwater depletion has increased significantly.
During 2000-2008, sea level rose 3.1 millimeters per year. Groundwater runoff accounted for 0.40 millimeters per year during that same time, 13% of the total sea level rise.
Image by kumaravel, used with Creative Commons license.