POL (Permanent Service for Oceanographic Levels)

POL is the Proudman Oceanographic Laboratory, the UK tidal and sea-level research institute at Bidston Observatory, later Liverpool, that hosted the Permanent Service for Mean Sea Level for decades before merging into the National Oceanography Centre in 2010. POL was not a predecessor of PSMSL and was not named the Permanent Service for Oceanographic Levels; it was the host laboratory, descended from the Liverpool Tidal Institute that Proudman founded in 1919 and where the analog tide-predicting machines were built. Its work covered harmonic tidal analysis, storm-surge modeling, and the long mean-sea-level records that PSMSL curates. The seed expansion and the predecessor claim are both incorrect.