QUALITY ASSESSMENT OF SEA LEVEL DATA by the UH SEA LEVEL CENTER/NATIONAL OCEANOGRAPHIC DATA CENTER JOINT ARCHIVE FOR SEA LEVEL updated: 30 Sep 2015 Station : Nouakchott Latitude: 17 59.4N Country : Mauritania Longitude: 016 02.2W JASL # : 806A Time Meridian: 015W (GMT - 01 hr) GLOSS # : none Originator #: NODC #: 71018501 Contributor : National Oceanography Centre Joseph Proudman Building 6 Brownlow Street Liverpool L3 5DA United Kingdom Originator : Port Autonome de Nouakchott Original Data: digital Instrmnt Type: OTT Kalesto radar sensor 2 x OTT ODS4-K pressure sensor (backup) Digitzd Intvl: 1 or 3 min Present Data : Hourly, daily, and monthly values obtained by: Hourly : Data provided to JASL at 15-minute intervals. Spot readings on the hour were made. 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 : 05 Jan 2007 - 09 Feb 2015 Gaps > 1 mon : 24 Feb 2008 - 10 Jun 2008;12 Sep 2009 - 02 Nov 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 : 2007-2015 Refernce Levl: All data refer to bolt on steel tube used as stilling well. Benchmark Description Bolt Bolt soldered onto pressure sensors steel tube near radar arm Datum Relationships: Chart Datum = 6.517m below Bolt Comment : 1) BODC notes: Amplitudes and phases of main tidal constituents have been compared with previously calculated values. Records have been visually inspected for spikes, datum shifts and timing errors. 2) JASL: gaps 24 hour or less were interpolated at the JASL. Many short gaps filled by interpolation Jul-Sep 2010. Difference with AVISO altimeter suggests a sinking of the tide station. The tide gauge is situated at the end of the main pier of the new jetty of Nouakchott harbour, near the meteorological observatory. CI MISSING REPLACED GAPS QUESTIONABLE YEAR (%) DATA OR BAD DATA FLUCTUATIONS ---- --- -------------------- --------------- -------------------- 2007 97 25-29,120-121, (11)164-(19)164 none 235-236 (18)205-(15)206 (10)275-(17)275 2008 69 613,55-162 (06)023-(14)023 none (19)054-(05)055 (17)171-(00)172 (12)245-(19)245 (14)254-(21)254 2009 83 133-145,255-306 (04)227-(11)227 none (14)227-(04)228 (11)362-(23)362 2010 93 101-110,202-203,206- (13)089-(04)090 none 208,213-215,221-223, (11)095-(18)095 227-230,239-242,251- (09)096-(04)097 256 (10)097-(19)097 (12)100-(22)100 (12)170-(19)170 (10)200-(22)200 (08)201-(20)201 (04)204-(22)204 (07)205-(22)205 (06)206-(20)206 (09)209-(23)209 (01)210-(20)210 (04)211-(20)211 (06)212-(20)212 (23)212-(11)213 (01)216-(20)216 (07)217-(22)217 (06)218-(21)218 (23)218-(21)219 (02)220-(20)220 (07)223-(00)224 (10)224-(02)225 (05)225-(19)225 (05)226-(20)226 (09)230-(02)231 (05)231-(21)231 (06)232-(00)233 (03)233-(00)234 (07)234-(21)234 (05)235-(21)235 (23)235-(17)236 (11)237-(23)237 (08)238-(22)238 (11)242-(01)243 (09)243-(16)243 (18)243-(04)244 (06)244-(22)244 (10)245-(05)246 (07)246-(23)246 (01)247-(23)247 (07)248-(21)248 (00)249-(22)249 (00)250-(14)250 (16)250-(01)251 (08)252-(23)252 (07)256-(23)256 (01)257-(08)257 (10)257-(00)258 (03)258-(23)258 (01)259-(12)259 (14)259-(23)259 2011 100 none (19)138-(13)139 none 2012 100 none (05)240-(12)240 none (21)266-(08)267 (15)271-(00)272 2013 93 62-63,170-191, none none 231-233 2014 97 227-228,247-249, (10)033-(17)033 none 256-265 (10)235-(19)235 (08)242-(17)242 (22)255-(07)256 (19)267-(03)268 (19)271-(02)272 (01)305-(20)305 (13)321-(11)322 (01)323-(10)323 (18)331-(11)332 2015 10 33-37 (07)018-(19)018 none