QUALITY ASSESSMENT OF SEA LEVEL DATA by the UH SEA LEVEL CENTER/NATIONAL OCEANOGRAPHIC DATA CENTER JOINT ARCHIVE FOR SEA LEVEL updated: 09 Sep 2020 Station : Seldovia, Cook Inlet,AK Latitude: 59 26.4N Country : USA Longitude: 151 43.2W JASL # : 561A Time Meridian: 150W (GMT - 10 hr) GLOSS # : none Originator #:9455500 NODC #: 75159101 Contributor : National Ocean Service (NOS) National Ocean. and Atmos. Administration (NOAA) N/OES22 SSMC4, STATION 7109 1305 East West Highway Silver Spring, MD. 20910-3233 Originator : same Original Data: digital Instrmnt Type: analog-to-digital (ADR) recorder (1975-1991); Aquatrak acoustic gauge, NOAA Next Generation Water Level Measuring System (NGWLMS) (1991-) Digitzd Intvl: six-minute NGWLMS sampling is three-minute average Present Data : Hourly, daily, and monthly values obtained by: Hourly : spot sampling on the hour 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 : 12 Jul 1975 - 31 Dec 2019 Gaps > 1 mon : 01 Jan 1976 - 01 Mar 1976;31 Mar 1976 - 01 Oct 1979 29 Dec 2010 - 10 Mar 2011;01 Nov 2015 - 30 Sep 2016 Time Refernce: GMT (hours 00-23) Space-filler Flag :-9999 Units : millimeters Missing Data Flag : 9999 Existing : Yes Operational : Yes Sat. Trans. : Yes Distribution : 1975-2019 Refernce Levl: All heights have been referred to the station tide staff zero which is linked to fixed bench marks. While standard mechanical or ADR instrument was the primary gauge, leveling calibration factors were applied monthly based on tide staff comparisons. Comment : The daily and monthly means reveal no apparent reference level changes. CI MISSING REPLACED GAPS QUESTIONABLE YEAR (%) DATA OR BAD DATA FLUCTUATIONS ---- --- -------------------- --------------- -------------------- 1975 43 281-295 none 280,296 1976 8 1-61,91-366 none none 1977 0 1-365 none none 1978 0 1-365 none none 1979 25 1-273 (14)365-(00)001 281-285,291-312,351 1980 95 59-76 none 16-26,36,223-231, 239,241-243,268-272, 329-332,354-360 1981 100 none (07)040-(00)041 125-129,144-146,152- 153,215,227,233,244, 283-305 1982 100 none none none 1983 100 none none none 1984 100 none none none 1985 100 none (18)200-(03)201 214-216 1986 100 none none none 1987 100 none none none 1988 100 none none none 1989 100 none none none 1990 100 none none 225 1991 100 none (14)365-(23)365 none 1992 100 none none none 1993 99 36-38 none none 1994 99 365 none none 1995 99 1-2 none none 1996 100 none none none 1997 99 314-317 none none 1998 100 none (00)011-(13)011 none 1999 100 none none none 2000 100 none none none 2001 100 none none none 2002 100 none none none 2003 100 none none none 2004 100 none none none 2005 100 none none 153-155,159 2006 100 none none none 2007 100 none none 80-86 2008 100 none none none 2009 100 none none 139 2010 94 281-300,363-365 none 195-196,202-205, 336,362-363 2011 81 1-69 none 151,160 2012 100 none none 28,149 2013 100 none none none 2014 100 none none none 2015 83 305-365 none none 2016 25 1-274 none none 2017 100 none none none 2018 100 none none none 2019 100 none none none