Global sea level rise is not cruising along at a steady 3 mm per year, it’s accelerating a little every year, like a driver merging onto a highway, according to a powerful new assessment led by CIRES Fellow Steve Nerem. He and his colleagues harnessed 25 years of satellite data to calculate that the rate is increasing by about 0.08 mm/year every year—which could mean an annual rate of sea level rise of 10 mm/year, or even more, by 2100.