Sea Level As We Experience It
By Ed Caryl
Nils-Axel Môrner is a Swedish sea level specialist. He claims that sea level is not rising more than about 1.1 mm/year, that the satellite data has been wrongly calibrated, and uplift and subsidence errors have contaminated the tide gauge records. In my research on sea level, some articles and papers show facts that indicate he might not be wrong.
The majority of tide gauges are at population centers that are also in areas where uplift and subsidence occur. For example, most of the east coast of the U. S. is subsiding, and most of Scandinavia is rebounding. The Pacific rim is very tectonically active with a mixture of up and down. So the real question is:
What is the sea level trend that most people are experiencing?
It is the sea level average trend for all tide gauges without any correction for uplift or subsidence. Here is that figure, their Figure 10, from here,
Figure 1 is a simple mean trend of all raw data from all tide gauges, with no corrections, simply normalized relative to their 1961 to 1990 values. The lower plot is the number of extant stations in each year. The trend in the upper plot from 1900 to 2000 is about 0.5 mm/year or less.
Figure 1 would seem to indicate that sea level might have been higher in 1900 than at present. This is not true. The problem is that in 1900 there were only 40 or 50 stations, and they were skewed toward stations with subsidence problems showing rapidly rising sea level. As the station numbers increased, more stations were added with uplift or stability, rather than added stations with subsidence, skewing the data in the opposite direction. But, the upper plot in Figure 1 is the sea level experience of most of the population.