Sea Level Thoughts

The global sea level data shown above comes from the NASA website. It’s unfortunate that NASA uses two different data sets (satellite in the top chart and tide gauges in the lower) to highlight the sea level changes. There’s nothing wrong with having both sets but to do a proper evaluation, the evaluator needs to see how the two data sets compare to one another where they overlap. Sea level changes from the depths of the Little Ice Age have actually been relatively consistent at ±1.6 mm/year based on the tide gauge data. As shown sea level changes do fluctuate to some degree. Obviously, something other than atmospheric CO₂ concentrations is affecting sea level rise (since CO₂ is rising very smoothly (once yearly seasonal fluctuations are removed)). Given that most of mankind’s CO₂ contribution has occurred since 1950, it seems strange that the sea level rise post 1950 actually decreased to 1.75 mm/year. Correct me if I’m wrong, but CO₂ was steadily rising which should have lead to temperature increases which should then in turn lead to escalating sea level rises. The 2.6 mm/year rise from 1930 to 1960 (tide gauge data), is very similar to the 2.8 mm/year rise between 1990 and 2015 (satellite data). So nowhere in this NASA data is the sea level data escalating to catastrophic levels. In fact, sea levels, as shown by the red line on the satellite data, have been essentially flat since late 2015.

The tide gauge data from New York (and many other places in the world) has been rising very steadily. In fact, anyone with a pencil and a ruler could have extrapolated the data from the late 18^th and early 19^th century to show that New York was going to have some issues with rising sea levels. We did not need Al Gore and his super computers (and the billions of dollars) to confirm that. You also don’t hear much discussion on the drop in sea level at New York since the peak in 2010 back to an average baseline. It is very possible that sea levels will continue to decline as temperatures drop due to lower solar activity through the Grand Solar Minimum.