evidence: Scientists have been tracking sea level along coastlines using tidal gauges for more than a century. And since the 1990s, satellite measurements have given them an even more complete view of sea level over the global ocean. Those data unequivocally show a rise in sea level. Averaged over the entire ocean, the increases are small—just three millimeters per year, or about the width of two grains of rice laid side by side. But those millimeters add up, with sea level rising more than seven centimeters (a little more than three inches) in just 25 years. What’s more, Piecuch says, "it’s not just rising, it’s accelerating. It’s rising faster every year." [...] Kopp, R.E. et al. 2016. Temperature-driven global sea-level variability in the Common Era. Proceedings of the National Academy of Sciences. doi: 10.1073/pnas.1517056113.