QUALITY ASSESSMENT OF SEA LEVEL DATA by the UH SEA LEVEL CENTER/NATIONAL OCEANOGRAPHIC DATA CENTER JOINT ARCHIVE FOR SEA LEVEL updated: 05 Nov 2019 Station : Baltra-B,Galapagos Is. Latitude: 00 26.2S Country : Ecuador Longitude: 090 17.1W JASL # : 003B Time Meridian: 090W (GMT - 6 hr) GLOSS # : 169 TOGA #: P082 NODC #: 50090001 Contributor : UH Sea Level Center 1000 Pope Rd. MSB 317 Honolulu, Hawaii 96822 Originator : Dept. of Oceanography University of Hawaii 1000 Pope Rd. MSB 317 Honolulu, Hawaii 96822 Original Data: digital Instrmnt Type: 1. Leupold and Stevens Analog-to-Digital Recorder (ADR); 1985-2003 2. Handar Encoder 436A (ENC) 1991- 3. Handar Encoder 436A (ENB) 10/1997-07/2007 4. radar (RAD) gauge (Vega Vegapuls 62), 2/2008- 5. pressure transducer, 2/2000- Primary channel used in JASL set: 1985-1990: ADR 1991-2007,2015-2018: ENC 2008-2014: RAD *short gaps in primary channel filled with other channels as available; see UHSLC for specific dates Digitzd Intvl: 15 (ADR,ENB); 2, 3 or 4 (ENC, RAD) minutes Present Data : Hourly, daily, and monthly values obtained by: Hourly : (pre-1987) Nine-point triangular filter centered on the hour with respective periods of the 95, 50, and 5% amplitude point of the filter response at 623.6, 177.0, and 103.7 minutes;(1987+) three-point Hanning filter centered 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 : 25 Mar 1985 - 31 Dec 2018 Gaps > 1 mon : 05 Jan 1988 - 04 Feb 1988;30 Jan 1995 - 08 Mar 1995 11 Feb 2002 - 18 Jul 2004;03 Jul 2007 - 13 Feb 2008 20 Jun 2015 - 30 Jul 2015 Time Refernce: GMT (hours 00-23) Space-filler Flag :-9999 Units : millimeters Missing Data Flag : 9999 Existing : Yes Operational : Yes Sat. Trans. : Yes Distribution : 1985-2018 Refernce Levl: Heights are referred to the station tide staff zero, which is linked to land-based benchmarks. This reference zero is unique to this station and is not an official datum (chart, national, etc.) and is not relative to local tidal parameters, such as mean lower low water. See the Originators for benchmark descriptions, maps, and the geodetic levelling history. Comment : The daily and monthly means do not reveal any reference level changes or trends and agree well with Santa Cruz. This station is distinguished from station Baltra-A because the tide staffs have not been levelled to common bench marks. The hourly data contain significant timing errors in 1988-1990 as noted below. Encoder data, as noted by * below, were used to fill some gaps. The primary calibration device (a reference level switch) had many questionable readings during 1995-1997; however, the level appears steady as seen in differences with Santa Cruz and La Libertad. Data not recoverable for 02/2002 - 07/2004. The JASL update of 05 Nov 2019 replaces 01 Jan 2016 - 05 Oct 2017. CI MISSING REPLACED GAPS QUESTIONABLE YEAR (%) DATA OR BAD DATA FLUCTUATIONS ---- --- -------------------- --------------- -------------------- 1985 77 none none none 1986 90 280-308,330-338 none none 1987 100 none none none 1988 92 5-35,107-108 (14)061-(23)061 121-140,152-153 (18)152-(23)152 *(00)035-(20)048 *(17)091-(11)107 1989 100 none (12)334-(23)334 152-161,168- *(18)001-(13)152 169,184-185,204,232- 234,258-264,271-280, 284-292,318-319,336- 362 1990 100 none (02)151-(21)151 30-32,56-60,84-092, (12)213-(23)213 098-105,113-150, 159-161 1991 100 none (10)202-(23)202 none *(00)274-(23)315 1992 99 317-322 (21)014-(20)015 none 1993 96 197-211 none none 1994 100 none (23)196-(11)197 none 1995 90 30-67 (21)082-(20)083 none (20)149-(13)150 1996 97 212-223 none none 1997 99 298-301 none none 1998 99 293-298 (02)040-(16)040 none 1999 100 none none none 2000 100 none none none 2001 98 1-5,25-27 none none 2002 12 42-365 none none 2003 0 1-365 none none 2004 45 1-200 none none 2005 100 none none none 2006 100 none none none 2007 50 184-365 none none 2008 88 1-44 none none 2009 100 none none none 2010 100 none (13)332-(23)332 none 2011 100 none (11)181-(18)181 none 2012 100 none none none 2013 100 none (13)174-(00)175 none (01)235-(08)235 2014 100 none (15)178-(23)178 none 2015 82 107-110,112-114,124- (19)133-(11)134 none 126,128-133,135-149, (18)169-(12)170 151-152,171-211 2016 100 none none none 2017 100 none none none 2018 100 none (21)233-(13)234 none