QUALITY ASSESSMENT OF SEA LEVEL DATA                
                                           by the                               
                   UH SEA LEVEL CENTER/NATIONAL OCEANOGRAPHIC DATA CENTER     
                                 JOINT ARCHIVE FOR SEA LEVEL                    
                                                                                
              Station  : Christmas                 Latitude:  10 25.0S          
              Country  : Australia                Longitude: 105 40.0E          
              JASL #   : 170A                 Time Meridian: 105E (GMT + 7 hr)  
              GLOSS #  : 047      TOGA #: I049       NODC #: 31100501           
              Contributor  : CSIRO                                              
                             Division of Oceanography                           
                             GPO Box 1538                                       
                             Hobart, Tasmania 7001                              
              Originator   : same                                               
              Original Data: digital                                            
              Instrmnt Type: Leupold Stevens analog-to-digital recorder         
              Digitzd Intvl: 15 minute 
              Present Data : Hourly, daily, and monthly values obtained by:     
                    Hourly : three-point Hanning 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 : 29 Sep 1986 - 19 Nov 1993
              Gaps > 1 mon : 18 Mar - 18 Apr 1987; 13 Jun - 25 Jul 1987
                             09 Oct 1987 - 10 Aug 1990;05 Apr - 24 May 1991
                             31 Aug 1992 - 29 Nov 1992
              Time Refernce: GMT (hours 00-23)   Space-filler Flag   :-9999     
              Units        : millimeters         Missing Data Flag   : 9999     
              Existing     : Yes                 Operational         : Yes      
              Sat. Trans.  : No                  Distribution        : 1986-1993
              Refernce Levl: All heights have been referred to the station tide 
                             staff zero which is linked to fixed bench marks.
                             The primary Tide Gauge Benchmark is labeled "CHS 1"
                             and is a circular brass plaque set in bedrock
                             between the two cantilever loaders in Flying
                             Fish Cove.
              Comment      : The daily and monthly means reveal no              
                             apparent reference level changes or trends and
                             agree reasonably well with Cocos Island.
                                                                                
                    CI MISSING              REPLACED GAPS     QUESTIONABLE      
              YEAR (%) DATA                 OR BAD DATA       FLUCTUATIONS      
              ---- --- -------------------- --------------- --------------------
              1986  27 none                 none            none                
              1987  57 77-108,164-206,      none            none                
                       282-365                                                  
              1988   0 1-366                none            none                
              1989   0 1-365                none            none                
              1990  33 1-222,275-299,333-   none            none                
                       334
              1991  78 7-35,95-144          none            none                
              1992  75 244-334              none            none
              1993  99 228-229              none            none