Sea Levels are Rising 60 Percent Faster than Anticipated

Sea levels are rising much faster than previously anticipated. Just how much sea levels will rise depends on what we do to reduce our greenhouse gas emissions.

The rate of sea level rise appears to be much faster than anticipated by the U.N. Intergovernmental Panel on Climate Change (IPCC).

According to a November 27th study, published in published in Environmental Research Letters, the ocean is rising much faster than predicted by the IPCC.

Based on satellite data, the 2012 study indicates that, “The rate of sea level rise of the past decades…is greater than projected by the IPCC models. This suggests that IPCC sea level projections for the future may also be biased low.”

As reviewed in Climate Central, the IPCC’s projections were significantly less than observed values due in large part to the fact that they did not adequately factor accelerated ice flows into the sea from Greenland and Antarctica.

The newly published figures still anticipate a 3-foot sea level increase by 2100. What is most shocking about the new study is the speed at which sea levels are rising. Between 1993 and 2011 the sea level has risen by about 3.2 millimeters per year. That’s 60 percent faster than the 2 millimeters per year the IPCC’s computer models suggested.

The report indicated that “Global warming has raised sea level about 8 inches since 1880.” The authors of the report expect the seas to rise another 20-80 inches by 2100.

Even at 3.2 millimeters per year, sea level would only go up by a foot by 2100; the extra 2 feet almost everyone expects will come from an accelerating sea level rise caused by ever increasing temperatures.

But 3 feet of sea level rise can be reversed if we act to reduce greenhouse gases. “A lot depends on what emissions path we follow,” Report co-author Grant Foster said. “If we get our acts together, it doesn’t have to go that high.”