Sea Level Surprises at Hilo

While doing research for my comment to EPA on their Proposed Finding that CO2 is a dangerous air pollutant, I ran across some data for sea level in Hawaii, taken at Hilo which is on the Big Island of Hawaii.  The data has some surprises, and quite frankly, I am asking for comment and insight from those who have a better understanding than I have.   

The first graph below (Figure 1) shows the same time period as does University of Colorado's sea level as measured by satellites.  The upward trend is roughly the same as the global average from U. Colorado, which shows 3.3 mm/year.  Figure 1 has 2.9 mm/year, or roughly 10 percent lower than the global average.  This makes sense to me, as Hawaii is almost in the middle of the Pacific Ocean and very tropical.  The ocean there should be warm, and expand along with the Pacific Decadal Oscillation in its warm phase. 

                                            Figure 1.  Rate of increase 2.9 mm/yr

Figure 2, shown below, has me puzzled, however.  This shows the sea level from 1978 through 2002, with an almost zero slope to the trend-line.  The very slight downward trend is negative 0.1 mm/year.  My puzzlement arises because this time period was reportedly during the warming phase of the Pacific Decadal Oscillation, and the ocean water surrounding Hawaii should have been warming, and therefore expanding.  The sea level is a function of ocean temperature, according to the climate scientists who incessantly tell us the globe is warming due to man-made CO2 emissions into the atmosphere.   How, then, could the sea level at Hilo, Hawaii, not be rising during 23 years?  We know that the CO2 in the atmosphere was rising steadily all during that time.  

                                             Figure 2. Rate of increase -0.1 mm/yr

Finally, Figure 3 shown below shows the entire record of sea level measured by the University of Hawaii researchers, from 1927 through 2008.  The overall trend is positive, with the rate of sea level increasing at 3.2 mm/year.   The rather flat trend from 1978 through 2002 is what aroused my curiosity. 

Another odd thing about Figure 3 is the increase in sea level from 1945 through 1961.  This was the same time period as a cold phase of the PDO. 

                                            Figure 3. Rate of increase 3.2 mm/yr

The information on the PDO and its phases is taken from JISAO at the University of Washington.  Something just does not add up, at least not to me.  

Any comments?

Roger E. Sowell, Esq.