The Permanent Service for Mean Sea Level’s (PSMSL) global mean sea level dataset

The Permanent Service for Mean Sea Level (PSMSL) is the internationally recognised global sea level data bank for long term sea level change information from tide gauges, responsible for the collection, publication, analysis and interpretation of sea level data. The PSMSL was founded 90 years ago, and today operates from the Liverpool site of the UK’s National Oceanography Centre. 

The PSMSL’s main product, a dataset of monthly and annual means from over 2000 locations worldwide aggregated from over 200 suppliers, is a cornerstone in our understanding of changes in sea level over the two centuries. For our highest quality Revised Local Reference (RLR) dataset, we ensure the data can all be referred to a fixed point on land, ensuring a consistent vertical reference frame is used throughout the record. Also, we provide vertical land movement information from permanent GNSS installations near each tide gauge, allowing users to compare our data to measurements from satellites and GNSS-IR data through our GNSS-IR data portal.

Here we present the PSMSL mean sea level dataset, ellipsoidal ties, and GNSS-IR, along with an overview of the dataset's status over the past few years. We also discuss ongoing efforts to improve the dataset and the quality of metadata we supply, and attempts to ensure they meet FAIR data practices (Findable, Accessible, Interoperable and Reusable).