Groundwater depletion contributes to sea level rise



Groundwater depletion is contributing substantially to sea level rise and will likely continue to do so over the next several decades, according to a new study by Wada et al. Much of the groundwater extracted for irrigation, drinking, and other uses does not wind up back in the ground but instead evaporates to the atmosphere and then returns to the surface as precipitation, which eventually makes its way to the oceans and leads to sea level rise. The authors reconstructed past groundwater depletion and its contribution to global sea level change and developed new projections for the 21st century based on models. They found that the contribution of groundwater depletion to global sea level increased from 0.035 millimeter per year in 1900 to 0.57 millimeter per year in 2000 and is projected to increase to 0.82 millimeter per year by 2050.