QUALITY ASSESSMENT OF SEA LEVEL DATA by the UH SEA LEVEL CENTER/NATIONAL OCEANOGRAPHIC DATA CENTER JOINT ARCHIVE FOR SEA LEVEL update: 26 May 1999 Station : Hong Kong-A,North Point Latitude: 22 18.0N Country : China Longitude: 114 12.0E JASL # : 329A Time Meridian: 120E (GMT + 8 hr) GLOSS # : 077 TOGA #: P003 NODC #: 12112401 Contributor : Hong Kong Observatory 134A Nathan Road, Kowloon Hong Kong Originator : same Original Data: analog Instrmnt Type: mechanical (float type) tide gauge Digitzd Intvl: one hour Present Data : Hourly, daily, and monthly values obtained by: Hourly : the one-minute average on the hour is taken as the mean hourly tide data 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 1962 - 31 Dec 1985 Gaps > 1 mon : 9 May - 5 Jul 1984 Time Refernce: GMT (00-23 hours) Space-filler Flag :-9999 Units : millimeters Missing Data Flag : 9999 Existing : No Operational : No Sat. Trans. : No Distribution : 1962-1985 Refernce Levl: The data are assumed to have been corrected to tide staff zero or fixed bench marks by the originators. This series is at a different location than 329B (Quarry Bay) and has not been geodetically survey to the same datum. Comment : The residuals (observed minus predicted data) contain a high degree of noise with periods of 3 to 8 hours. This may be due to the insufficient approximation of the observed data by the tidal analysis. The residuals contain fluctuations of up to 75 cm with periods of 1 to 3 days associated with meteorological events. Otherwise, the daily and monthly means do not reveal any reference level shifts or obvious problems. CI MISSING REPLACED GAPS QUESTIONABLE YEAR (%) DATA OR BAD DATA FLUCTUATIONS ---- --- -------------------- --------------- -------------------- 1962 97 102-104,244-246, (12)263-(23)263 7-8,92-94,109,218, 251-258 (16)336-(00)337 349,363 1963 99 44-46 none 39,40,227,334,343- 344 1964 99 18-20,250-252 (16)201-(15)202 25,131-133,220-222, (16)230-(15)231 248-250,253-254, 298,335 1965 100 none (16)274-(15)275 107,121,136,160, (16)280-(15)281 195-197,213,329, 358-359 1966 100 none none 43,54,68,77,84-85, 334 1967 92 269-283,285-296 (15)227-(23)227 71,93-94,264 (12)307-(23)307 1968 99 133-135 (03)170-(23)170 233-235,273 (05)179-(23)179 1969 100 none (11)035-(23)035 13,15,209 (07)328-(15)328 1970 100 none none 256-257 1971 100 none (15)360-(23)360 28,55,168-169,203, 228,244,278-280,333 1972 100 none (06)084-(13)084 91,100,326,337-338 (03)095-(11)095 (12)267-(18)267 1973 100 none (14)101-(00)102 50,257-259,287-291, (16)243-(23)243 293,335-336 (15)246-(23)246 1974 100 none none 285-286,291-292, 317-319,349,352 1975 100 none none 2,41,131,295-296 1976 100 none (05)030-(18)030 31-34,79,103-104 1977 100 none (16)328-(23)328 83,267,318 (01)359-(08)359 1978 99 58-59 (06)084-(13)084 8,16,63-64,81,83, (03)095-(11)095 207,238-239,262- (12)267-(18)267 263,300,318,356-359 1979 100 none none 92-95,103-104 1980 99 296-298,315-317 none 9,16-17,92,105,203- 204,271-272 1981 99 320-322,348-349 (01)338-(23)338 none (04)350-(20)350 (04)351-(20)351 (00)352-(15)352 (05)354-(23)354 1982 87 169-187,323-349, (15)243-(23)243 none 360-362,363-365 1983 93 1-7,224-225, (17)030-(23)030 25-29,31-33,41-45, 238-255 66,141,286 1984 78 109-121,125-128, (00)026-(23)026 70-71 130-187,191-195, 245-249,364-366 1985 97 49-56,225-226, (16)009-(22)009 88 237-239,333-336, (03)172-(10)172 365 (18)232-(00)233 (10)233-(00)234