March 23, 2013 — Rev 0.7, added a spreadsheet with just the 45 NOAA-administered GLOSS-LTT tide stations,
and also one with just the 42 of those 45 for which there was data through 2011. (The other
stations were three Pacific Islands: Johnston Atoll, Pago Pago, and Chuuk.)
In 2012 NOAA recalculated sea-level trends for those
42 U.S. tide gauges
using data through 2011. The results were illuminating.
The sea-level records for the 42 gauges had an average duration of 87.4 years (through 2011),
and NOAA's calculated trends had an average confidence interval of ±0.515 mm/yr.
When new (through 2011) trends were compared to the old (through 2006) trends, 23 sites showed
slight declines in the rate of sea-level rise, and 19 showed slight increases.
A simple, unweighted average of the 42 gauges comes to 2.025 mm/yr average rate of SLR through 2006,
or 2.026 mm/yr through 2011 (a difference of one one-thousandth of a millimeter/year), or 1.286 mm/yr
if you include Peltier's VM2 GIA adjustments.
The bottom line is that, as measured by the 42 best U.S. long-term trend tide stations,
the average rate of sea-level rise over the 5-year period from 2006-2011 is virtually identical
to the rate for the full data record (averaging 87.4 years duration) -- more proof that there's
been no detectable acceleration in rate of sea-level rise in response to elevated CO2 levels.