QUALITY ASSESSMENT OF SEA LEVEL DATA by the UH SEA LEVEL CENTER/NATIONAL OCEANOGRAPHIC DATA CENTER JOINT ARCHIVE FOR SEA LEVEL updated: 08 Oct 2020 Station : Galveston,Pier 21,TX Latitude: 29 18.6N Country : USA Longitude: 094 47.6W JASL # : 775A Time Meridian: 090W (GMT - 6 hr) GLOSS # : 217 Originator #:8771450 NODC #: 72099401 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 : US Coastal Geodetic Survey (1904-1972);NOS (1973+) Original Data: analog (1904-1974); 1974+ digital Instrmnt Type: 1) float/well system, standard analog (1904-1974); 2) float/well system, Fischer and Porter ADR punch-paper tape (1974-1992); 3) Aquatrak acoustic gauge, NOAA Next Generation Water Level Measuring System (NGWLMS) (1993-) Digitzd Intvl: spot hourly (1904-1974); 6 min (1974-) NGWLMS sampling is three-minute average Present Data : Hourly, daily, and monthly values obtained by: Hourly : The original digitizing interval was hourly (standard); spot sampling on the hour (adr/NGWLMS) 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 1904 - 31 Oct 2019 Gaps > 1 mon : 02 Aug 1915 - 08 Sep 1915;11 Oct 1929 - 05 Dec 1929 03 Jan 1930 - 08 Feb 1930;02 Jul 1943 - 15 Oct 1943 01 Jan 1972 - 31 Dec 1973;08 Oct 1976 - 13 Jan 1977 02 May 1984 - 27 Oct 1984;23 May 2009 - 23 Oct 2009 Time Refernce: GMT (hours 00-23) Space-filler Flag :-9999 Units : millimeters Missing Data Flag : 9999 Existing : Yes Operational : Yes Sat. Trans. : Yes Distribution : 1904-2019 Refernce Levl: The sea level heights are referred to the tide gauge datum. Additional information available from the data originators. 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. Pier 21 is on the inside of the island. Pleasure Pier is located nearby yet facing the Gulf of Mexico. CI MISSING REPLACED GAPS QUESTIONABLE YEAR (%) DATA OR BAD DATA FLUCTUATIONS ---- --- -------------------- --------------- -------------------- 1904 99 1 none none 1905 100 none none none 1906 100 none none none 1907 100 none none none 1908 100 none none none 1909 100 none none none 1910 100 none none none 1911 100 none none none 1912 100 none none none 1913 100 none none none 1914 100 none none none 1915 90 214-251 none none 1916 67 32-152 none none 1917 100 none none none 1918 100 none none none 1919 100 none none none 1920 100 none none none 1921 95 274-293 none none 1922 100 none none none 1923 100 none none none 1924 100 none none 136-139 1925 100 none none none 1926 100 none none none 1927 100 none none none 1928 100 none none none 1929 80 284-339,342-345, none none 352-364 1930 90 3-39,54-56 (02)059-(19)059 none 1931 100 none none none 1932 100 none none none 1933 96 76-91 none none 1934 100 none none none 1935 94 56-80 none none 1936 100 none none none 1937 100 none none none 1938 100 none none none 1939 100 none none none 1940 100 none none none 1941 100 none none none 1942 100 none none none 1943 71 183-288 none none 1944 100 none none none 1945 100 none none none 1946 100 none none none 1947 100 none none none 1948 100 none none none 1949 100 none none none 1950 100 none none none 1951 100 none none none 1952 100 none none none 1953 100 none none none 1954 100 none none none 1955 100 none none none 1956 96 117-130 none none 1957 100 none none none 1958 100 none none none 1959 100 none none none 1960 100 none none none 1961 100 none none none 1962 100 none none none 1963 100 none none none 1964 100 none none none 1965 100 none none none 1966 100 none none none 1967 100 none none none 1968 98 36-43 none none 1969 100 none none none 1970 100 none none none 1971 100 none none none 1972 0 1-366 none none 1973 99 10-11,26-28 none none 1974 100 none none none 1975 96 266-282 none none 1976 73 52-61,64-67,214-218, (14)272-(12)273 none 282-366 1977 96 1-13 none none 1978 97 230-240 none none 1979 77 47-68,124-153,177- (05)210-(23)210 none 180,214-244 1980 99 354-357 (17)056-(08)057 130,140 (23)259-(19)260 1981 100 none none none 1982 99 85-89 (19)202-(15)203 none 1983 100 none none none 1984 51 123-301 none none 1985 99 36-37 none none 1986 100 none none none 1987 100 none none none 1988 99 243-246 none none 1989 100 none none none 1990 100 none none none 1991 100 none (04)036-(21)036 none 1992 100 none none none 1993 100 none none none 1994 97 34-35,42-45,49-51, none none 70-73 1995 100 none none none 1996 100 none none none 1997 100 none none none 1998 100 none (19)253-(13)254 none 1999 99 19-21,167-169 (20)017-(13)018 none (17)018-(13)019 (19)166-(04)167 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 none 2006 100 none none none 2007 100 none none none 2008 99 257-259 none none 2009 58 143-296 none none 2010 100 none none none 2011 100 none none none 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 100 none none none 2019 83 none none none