Figure 4. Annualized mean sea level changes from 1993 to 2011 at the Portland, ME tidal station, including seasonal signals. Over this time period, sea level has risen at a rate of about 4.2 mm per year, equal to about 16.5 inches per century. Error bars show the calculated standard error for the entire dataset. Data courtesy of NOAA's Tides & Currents website.
Last updated on April 30, 2012