Water levels

Water levels are the observed sea and lake surface heights at a station, the core CO-OPS time series: 301 active and 2,922 historic stations deliver 1-minute through monthly-mean intervals with per-request window limits by interval.

In this catalog it appears concretely: - NOAA CO-OPS coverage.geographic — "301 active water-level stations, 2,922 historic water-level stations". - NOAA CO-OPS coverage.temporal Per-request limits: 4 days (1-min), 1 month (6-min), 1 year (hourly/high-low), 10 years (daily), 200 years.

Conventions decide whether two sources can be joined at all. Buy one side of an analysis that ignores this convention and every reconciliation step — calendar alignment, unit conversion, entity matching — lands on your team instead of the vendor's.

The failure mode is concrete: the label appears in a listing, the delivered files tell a different story, and the gap surfaces mid-project when fixing it is most expensive.

You rarely have to take a vendor's word for it. 82.4% of the 1,744 datasets Datadory catalogs are free to access, and NOAA CO-OPS coverage.geographic lets you inspect the real artifact before any budget is committed.

Treat every claim of this attribute as testable:

1. Open NOAA CO-OPS coverage.geographic and confirm its record — "301 active water-level stations, 2,922 historic water-level stations" — against the files you actually receive.
2. Open NOAA CO-OPS coverage.temporal Per-request limits: 4 days (1-min), 1 month (6-min), 1 year (hourly/high-low), 10 years (daily), 200 years and compare its listing against the delivered artifact before paying for a commercial equivalent.
3. Pin down update cadence in writing. Across this catalog, 22.6% of 1,744 datasets refresh daily and 64 still arrive only through a manual request form, so ask exactly how fresh each release is.
4. Check whether definitions are verified at all. Field definitions are verified for 1495 of 1,744 datasets (85.7%), and any source you license should meet that bar.
5. Price the delivery route before the license. In this catalog bulk download is the most common access method (725 datasets) ahead of official APIs (574), and 379 sources still require scraping — a maintenance cost that lands on you, not the vendor.

See the term applied to real records: marine-ports-services data, marine-transportation data.

Adjacent concepts worth reading next: - currents - PORTS installations - Tide predictions