According to Worldwatch:

Sea level rise could be even higher than predicted this century.

Sea level rise could be even higher than predicted this century.

“The average sea level around the world has risen a total of 222 millimeters (mm) since 1875, which means an annual rate of 1.7 mm (See Figure 1.) Yet at the end of this long period, from 1993 to 2009, the sea level rose 3.0 mm per year—a much faster rate.

An estimated 30 percent of the sea level increase since 1993 is a result of warmer ocean temperatures that cause the water to expand (thermal expansion).

Another 55 percent of the increase results from the melting of land-based ice, mainly from glaciers and the Greenland and Antarctic ice sheets. (Sea ice that melts does not contribute to sea level rise, as the volume remains constant.)

The other 15 percent of the rise is due to changes in terrestrial freshwater dynamics, such as wetland drainage and lowered water tables.”

Image credit: Flickr/climatesafety