Same source. This site reads from the same Irish Lights buoy instrument (MMSI 992501301) as the CIL MetOcean website. The raw sensor data is identical.

Hourly observations come from the Irish Lights MetOcean API, which publishes once per hour. Irish Lights sometimes retroactively correct these values after initial publication, so numbers on the CIL website may shift slightly after the fact.

Live AIS updates (when the green dot is showing) come directly from the buoy’s radio broadcast every ~3 minutes - fresher and more frequent than what the CIL website shows.

Minor differences with the CIL website can occur due to rounding, post-processing corrections applied by Irish Lights after we’ve already captured the reading, and timing (our snapshot vs. their later-corrected value). Neither is wrong - the raw instrument reading is the same.

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