QUALITY ASSESSMENT OF SEA LEVEL DATA by the UH SEA LEVEL CENTER/NATIONAL OCEANOGRAPHIC DATA CENTER JOINT ARCHIVE FOR SEA LEVEL updated: 30 Oct 2019 Station : Apia-B Latitude: 13 49.2S Country : Western Samoa Longitude: 171 45.4W JASL # : 401B Time Meridian: 165W (GMT - 11 hr) GLOSS # : none Originator #: ID070012 NODC #: 51173101 Contributor : National Tidal Centre, Bureau of Meteorology PO Box 421 Kent Town SA 5071 South Australia AUSTRALIA Originator : same Original Data: digital Instrmnt Type: Aquatrak acoustic gauge (SEAFRAME) Digitzd Intvl: 6 minute (average of 181 one minute samples) Present Data : Hourly, daily, and monthly values obtained by: Hourly : Cosine-Lanczos filter with cutoff of 120 min. 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 : 27 Feb 1993 - 31 Dec 2018 Gaps > 1 mon : 08 Oct 2002 - 11 Dec 2002;24 May 2010 - 29 Jun 2010 02 Jul 2010 - 31 Aug 2010;18 Jul 2018 - 22 Aug 2018 Time Refernce: GMT (hours 00-23) Space-filler Flag :-9999 Units : millimeters Missing Data Flag : 9999 Existing : Yes Operational : Yes Sat. Trans. : Yes Distribution : 1993-2018 Refernce Levl: All heights have been referred to the station Tide Gauge Zero (TGZ), which is linked to fixed bench marks. The height datum is Mean Sea Level derived from BM 48 in the 1993 survey. Height of Seaframe Sensor Bench Mark (SSBM) above TGZ is 4.8706m. Comment : High resolution coordinates are: Lat: 13 deg 49 min 09 sec S Lon: 171 deg 45 min 21 sec W The daily and monthly values are reasonable and do not reveal any obvious reference level shifts. Comparisons with daily means from satellite altimetry suggest a subsidence of the island ~8cm causing an apparent sea level rise after the earthquake of 29 Sep 2009. SPECIAL NOTE TO USERS OF NAT. TIDAL CENTRE DATA: As a user of this information, you are deemed to have read and accepted the conditions described in the Copyright Notice and Disclaimer at: http://www.bom.gov.au/other/copyright.shtml CI MISSING REPLACED GAPS QUESTIONABLE YEAR (%) DATA OR BAD DATA FLUCTUATIONS ---- --- -------------------- --------------- -------------------- 1993 84 none none none 1994 100 none none none 1995 100 none (00)355-(00)356 none 1996 99 302-304 none none 1997 100 none none none 1998 100 none none none 1999 100 none none none 2000 100 none none none 2001 100 none none none 2002 83 281-345 none none 2003 100 none none none 2004 100 none none none 2005 98 58-67 none none 2006 100 none none none 2007 97 203-213,272-275 none none 2008 100 none none none 2009 100 none none none 2010 63 124-132,139-142,144- none none 180,183-272 2011 88 61-83,139-140,166- none none 180,236-242 2012 100 none none none 2013 100 none none none 2014 100 none none none 2015 100 none none none 2016 100 none none none 2017 100 none none none 2018 90 199-234 none none