I believe this is what you are referring to;

Figure 5 is a "detrended" record of the sort that corrects for a phenomenon that places all European and North American tide gauge data in doubt. The phenomenon is known as "Post Glacial Rebound" (PGR). During the last Ice Age, the region in which Stockholm was located was buried under several kilometers of ice. The Ice Age ended about 10,500 years ago with a rapid melting of the ice sheets over Europe and North America. Their melting resulted in sea level rise. And, with the ice gone, the plasticity of the mantle below the solid crust of the earth began to force the crust upward because the dead weight of the ice no longer was present. This process has gone on since the last Ice Age, is happening now, and will continue to do so well into the future.
PGR is underway all over Europe, North America, and east Asia (see Figure 6). [34] These are the continents most affected by the enormous ice sheets. Those regions weighed down by ice (those bounded by the continuous red line) continue to uplift like Sweden. This, in turn, causes peripheral regions around the margins of the former ice masses (bounded by the dashed red line) to subside as the continental crusts adjust and rebalance to the weight redistribution.

The North Atlantic actually is a huge basin semi-enclosed by continental landmasses. A 1400 nautical mile gap between west Africa and South America connects it to the world's other oceans. This may explain partly why long-term tide gauge records from within that basin are not always consistent with records outside. It also is unfortunate that all the really old tide gauge records (those that extend back into the 19th Century) come from Europe – the center of the PGR zone. Later American records are affected similarly.

There is a clear example of PGR from the steady rise in relative sea level at Trieste, Italy. Trieste is located at the northern end of the Adriatic Sea where there are hardly any tides to complicate sea level measurements.

The Trieste record mirrors that of Venice, across the Gulf of Venice. Because northern Italy is on the margins of where the great ice sheets were located during the last Ice Age, the steady and largely linear rise in sea level from 1905 (amounting to about 15 cm or nearly 6 inches) clearly is unrelated to transient climate events. Rather, it has an underlying geological cause, namely PGR. This long-term rise pre-dates 1905. Compare paintings by 18th Century artists Francesco Guardi and Canaletto with modern photographs of Venice’s famous Rialto Bridge (Figure 8). The comparison reveals a sea level much lower than the 15 cm represented in Trieste’s 20th Century tide gauge record.

Part of the climate unrelated to sea rise theory of the article.