SMHI oceanographic observations (Sweden)

What it is: Hourly and minute sea levels from Swedish stations, with a corrected hourly archive back to the start of each station.
Publisher: SMHI (Swedish Meteorological and Hydrological Institute).
What OTC takes: Gauge records that OTC fits. No harmonic constants are published. Tides are small except in the Skagerrak and Kattegat, so these sets mainly add completeness and Baltic datums.
Licence: Creative Commons Attribution 4.0 SE (CC BY 4.0 SE), as stated in SMHI's terms of use. Commercial use is allowed. Users must name SMHI as the source and say whether the material was changed.
Attribution line OTC uses: “Contains data from SMHI, CC BY 4.0 SE. Changed: OTC fitted harmonic constants from the sea-level records.”
Access and watching: Keyless REST API (CSV). SMHI asks users to avoid mass downloads and repeated fetches, so OTC fetches the corrected archive once and then only new records, weekly.
Coverage: 71 Swedish sea-level stations.
Rank: Gauge fit.