QUALITY ASSESSMENT OF SEA LEVEL DATA by the UH SEA LEVEL CENTER/NATIONAL OCEANOGRAPHIC DATA CENTER JOINT ARCHIVE FOR SEA LEVEL update: 27 Apr 2015 Station : Clipperton-C Latitude: 10 16.8N Country : France Longitude: 109 13.3W JASL # : 391C Time Meridian: 105W (GMT - 7 hr) GLOSS # : 165 Originator #: NODC #: 71100901 Contributor : Service Hydrographique Et Oceanographique (SHOM) De La Marine Establissement Principal 13 rue du Chatellier, Brest, Cedex, FRANCE Originator : SHOM/French Navy Original Data: digital Instrmnt Type: pressure tide gauge Digitzd Intvl: unconfirmed Present Data : Hourly, daily, and monthly values obtained by: Hourly : unconfirmed Daily : 119-point convolution filter (Bloomfield, 1976) centered on noon applied to the hourly data with respective periods of the 95, 50, and 5% amplitude points at 124.0, 60.2, and 40.2 hours Monthly: Simple average of all daily values; calculated if 7 or fewer days are missing Span of data : 09 Apr 2007 - 28 May 2008 Gaps > 1 mon : none Time Refernce: GMT (00-23 hours) Space-filler Flag :-9999 Units : millimeters Missing Data Flag : 9999 Existing : No Operational : No Sat. Trans. : No Distribution : 2007-2008 Refernce Levl: Chart Datum at Clipperton is defined 2.82m below benchmark A (nail sealed into a rock in the south of the island and 26.59m below IAG-GRS80 of ITRF08 (August 2011). The same referencing was tried between deployments of pressure gauges 2007-2008 and 2011-2012. Uncertainty of ~15cm exists between deployments. Difference of daily data with satellite altimeter (AVISO) also suggest ~15cm difference. Thus, the series are separated for 2007-08 and 2011-12, as 391C and 391D respectively. Historic short series are also available as 391A and 391B. Comment : Timing is of good quality. CI MISSING REPLACED GAPS QUESTIONABLE YEAR (%) DATA OR BAD DATA FLUCTUATIONS ---- --- -------------------- --------------- -------------------- 2007 73 none none none 2008 40 none none none