The Marshall Islands and their Sea Level Changes

Ron Broberg says:
August 1, 2013 at 1:01 pm
[…] In short, look around and take Dr, Mörner with a grain or two of sea salt.

Why would you say that?
From THE EXECUTIVE SUMMARY, IPPC TAR (2001), Chapter 11, Page 641
http://www.grida.no/climate/ipcc_tar/wg1/pdf/TAR-11.pdf

The sum of these components indicates a rate of eustatic sea level rise (corresponding to a change in ocean volume) from 1910 to 1990 ranging from –0.8 to 2.2 mm/yr, with a central value of 0.7 mm/yr. The upper bound is close to the observational upper bound (2.0 mm/yr), but the central value is less than the observational lower bound (1.0 mm/yr), i.e., the sum of components is biased low compared to the observational estimates. The sum of components indicates an acceleration of only 0.2 mm/yr/century, with a range from –1.1 to +0.7 mm/yr/century, consistent with observational finding of no acceleration in sea level rise during the 20th century.

Tide gauge sea level rise for the 20th century is about 1.7mm/yr. For the satellite record (1992 – present), it is 3.1 mm/yr (or 2.8 without glacial isostatic adjustment).
policycritic posted a quote from the 2001 IPCC report. 12 years have passed and there is more information. IPCC 2007 (AR4) didn’t say much about acceleration, but the leaked AR5 coming out this year said:

While significant uncertainties remain, understanding of sea level rise, particularly over recent decades but also for the 20th century as a whole, has improved significantly and it is now possible to account for much of the observed global mean sea level rise using both observations and process-based models of ocean thermal expansion and the melting of glaciers and the Greenland Ice Sheet. These models simulate the observed increase in the rate of rise during the last two decades…

From my reading of the recent literature, there is at best moderate certainty about recent acceleration (global, not local).
davidmhoffer said:

Nice try Eli. Why does the graphic end in 2008? We got 20 years of data but let’s skip the last 25% of it?

A fair point, but it can equally be applied to Morner’s – rather brief – analysis, which only goes up to 2010. Include recent data and there does indeed appear to be accelerated sea level rise at Majuro.
But I’m skeptical of claims of local trends at such short time scales. I’d like to see a proper analysis with all data and confidence intervals. I hereby politely ask Morner to try again with the recent data, and to show the results he gets with uncertainties.
Off to see if Tamino did that.

Global Sea Levels are rising. Not sure why you bother cherry picking one location.