QUALITY ASSESSMENT OF SEA LEVEL DATA by the UH SEA LEVEL CENTER/NATIONAL OCEANOGRAPHIC DATA CENTER JOINT ARCHIVE FOR SEA LEVEL updated: 17 Nov 2000 Station : La Union-A Latitude: 13 20.0N Country : El Salvador Longitude: 087 49.0W JASL # : 086A Time Meridian: 090W (GMT - 6 hr) GLOSS # : none TOGA #: none NODC #: 71083701 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 : U.S. Coast and Geodetic Survey; Dept. of Commerce Original Data: analog Instrmnt Type: standard float/well Digitzd Intvl: hourly 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 : 01 Jan 1954 - 12 Nov 1980 Gaps > 1 mon : 18 May 1954 - 23 Jul 1954;20 Jan 1955 - 07 Mar 1955 20 Jun 1955 - 15 Aug 1955;10 Oct 1955 - 28 Nov 1955 16 Apr 1957 - 11 Jun 1957;05 Aug 1960 - 23 Sep 1960 01 Jun 1964 - 01 Jul 1964;01 Dec 1965 - 01 Jan 1966 Time Refernce: GMT (hours 00-23) Space-filler Flag :-9999 Units : millimeters Missing Data Flag : 9999 Existing : No Operational : No Sat. Trans. : No Distribution : 1954-1980 Refernce Levl: All heights have been referred to the station tide staff zero which is linked to fixed bench marks. For 1954-1966, data were digitized at the Univ. of Hawaii Sea Level Center. Tide staff readings were provided; however, it appears the corrections to a fixed datum were already applied to the tabulated heights. For 1971-1980, Dr. Doug Luther oversaw the key entry of the data. It appears that the two segments (1954-1966 and 1971-1980) are tied to the same datum; however, this has not been confirmed. The long term difference with Balboa, Panama agrees well with La Union. Comment : There are no obvious reference level shifts. Timing is good except for select periods as noted below. La Union-A is separate from La Union-B due to a difference in reference levels. CI MISSING REPLACED GAPS QUESTIONABLE YEAR (%) DATA OR BAD DATA FLUCTUATIONS ---- --- -------------------- --------------- -------------------- 1954 76 1,138-204,281-288, (06)034-(05)035 none 295-302,351-358 (06)090-(05)091 1955 39 20-66,73-80,87-94, (18)008-(05)009 99-101 101-108,143-150,171- (05)243-(21)243 227,234-241,255-262, 269-276,283-332, 339-360 1956 75 22-29,36-43,113-120, none 251-254 155-162,204-211,218- 225,232-239,260-267, 274-302,323-330 1957 77 106-162,169-176,323- (18)236-(05)237 300-301 330,337-344,351-358 1958 100 none (00)204-(14)204 265 (00)204-(14)204 1959 71 155-162,190-197,204- none none 211,218-225,232-239, 246-253,260-267,274- 281,288-309,316-323, 330-337,344-351, 358-365 1960 73 120-134,141-148,190- (16)088-(23)088 none 197,204-211,218-267, 295-302,351-358 1961 100 none (06)025-(15)025 none (02)076-(18)076 (00)317-(08)317 1962 100 none (22)194-(06)195 343-344 1963 100 none (00)181-(08)181 none (01)244-(13)244 1964 92 153-183 1965 92 335-365 (00)223-(09)223 none (00)230-(07)230 (22)253-(05)254 1966 99 1 (04)091-(11)091 350,361 (07)136-(14)136 (04)289-(17)289 1967 0 1-365 none none 1968 0 1-366 none none 1969 0 1-365 none none 1970 0 1-365 none none 1971 99 95-97 (12)066-(23)066 none (07)095-(03)096 (04)239-(13)239 (05)326-(22)326 1972 100 none (22)262-(05)263 none 1973 98 23-26,29-32 (14)001-(23)001 none (21)014-(05)015 (14)016-(23)016 (10)077-(20)077 (04)242-(17)242 (00)298-(07)298 1974 100 none (12)063-(21)063 none (12)063-(21)063 (00)273-(09)273 (14)302-(23)302 1975 100 none (06)119-(17)119 none (07)190-(14)190 (02)214-(11)214 (02)240-(09)240 (12)245-(20)245 (04)309-(11)309 1976 92 33-38,122-128, (10)018-(21)018 none 137-153 (00)118-(07)118 (23)186-(14)187 (01)243-(08)243 1977 100 none (06)039-(19)039 none (15)060-(22)060 (08)095-(15)095 (04)236-(11)236 (01)250-(10)250 1978 99 333-335 (07)052-(16)052 none (08)074-(17)074 (19)076-(02)077 (07)181-(16)181 (04)195-(11)195 (17)304-(23)304 1979 96 343-357 (06)183-(14)183 335-336 (12)329-(19)329 1980 86 96-98 (00)063-(07)063 193-201 (02)202-(09)202 (05)217-(16)217