The Search for Acceleration, part 8, HawaiiAugust 16, 2013
This is part 8 of a series of posts in which I am searching for a large acceleration in sea level rise rate in the latter part of the 20th century. Such a rise rate acceleration is needed to reconcile the 1.8 mm per year average rise rate for the century attributed to tide gauge data and the approximately 3 mm per year rise rate for the tail end of the century attributed to the satellite data.
There are only four tide gauge stations in Hawaii with at least 90% of the data from 1960 to 2008. One of them has good data back to 1910. Evaluation of this small set of data sites is very simple and I will use the usual technique of detrending, weighting, averaging and derivatives, as shown in the following slide show. (Note that you can pause or increment the slide show forward or backward by using the buttons that appear when your cursor is placed over the image.)
It is very hard to make an argument in support of a century end acceleration in sea level rise rate based on this Hawaiian data.
SInce I removed the ENSO correlated component of the sea level for Western North America and for Australia, it stands to reason that the same thing should be done for Hawaii. See here for the math.
The top graph in the following image shows the weighted, detrended, averaged Hawaiian sea level (white), ENSO3.4 sea surface temperature (blue), and the component of sea level data that is orthogonal to the ENSO3.4 data (red). The bottom graph shows the corresponding relative rise rates associated with sea level (white) and with the ENSO orthogonal component of the sea level (red). All data is through a 5 year FWHM Gaussian filter.
See an index of the Search for Acceleration series here.
20th century rise rate average of 1.8 mm/year
Satellite data (about 3 mm/year): CU Sea Level Research Group
RLR tide gauge data: Permanent Service For Mean Sea Level
ENSO/Global warming relationship: Cobb, et. al., Science, 339, 1/4/13