QUALITY ASSESSMENT OF SEA LEVEL DATA                
                                           by the                               
                   UH SEA LEVEL CENTER/NATIONAL OCEANOGRAPHIC DATA CENTER     
                                 JOINT ARCHIVE FOR SEA LEVEL                    
                                       updated: 23 Sep 2003
              Station  : Rarotonga-A               Latitude:  21 12.4S
              Country  : Cook Islands             Longitude: 159 46.5W
              JASL #   : 023A                 Time Meridian: 150W (GMT - 10 hr) 
              GLOSS #  : 139      TOGA #: P064       NODC #: 52151901           
              Contributor  : UH Sea Level Center                              
                             1000 Pope Rd. MSB 317                              
                             Honolulu, Hawaii 96822                             
              Originator   : same
              Original Data: digital                                            
              Instrmnt Type: 1. (Apr 1977 - Dec 1984 )Fischer and Porter       
                                 Analog-to-Digital Recorder (ADR)               
                             2. (Dec 1984-1997) Leupold and Stevens 
                                 Analog-to-Digital Recorder (ADR);              
                             3. (Dec 1984-1997) Handar Encoder (ENC) 
                             Primary gauge: ADR:1977-90, ENC 1991-1997
              Digitzd Intvl: 15 (ADR); 3 or 4 (ENC) minutes
              Present Data : Hourly, daily, and monthly values obtained by:     
                    Hourly : (pre-1987) Nine-point triangular filter centered   
                             on the hour with respective periods of the 95, 50, 
                             and 5% amplitude point of the filter response at   
                             623.6, 177.0, and 103.7 minutes;(1987+) three-point
                             Hanning filter centered on the hour (UHSLC)
                    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 : 24 Apr 1977 - 09 Dec 1997
              Gaps > 1 mon : 2 Jan - 14 Feb 1987                                
              Time Refernce: GMT (hours 00-23)   Space-filler Flag   :-9999     
              Units        : millimeters         Missing Data Flag   : 9999     
              Existing     : Yes                 Operational         : Yes      
              Sat. Trans.  : Yes                 Distribution        : 1977-1997
              Refernce Levl: Heights are referred to the station tide staff 
                             zero, which is linked to land-based benchmarks. 
                             This reference zero is unique to this station and
                             is not an official datum (chart, national, etc.) 
                             and is not relative to local tidal parameters, 
                             such as mean lower low water.  See the Originators
                             for benchmark descriptions, maps, and the geodetic
                             levelling history.

                             Series 023A is separate from 023B (National Tidal
                             Facility, Australia) because they are at different
                             locations.  
              Comment      : The daily and monthly means reveal no apparent     
                             changes in the reference level.  The severe weather
                             events of 22-26 Feb 1986, 1 - 4 Jan 1987, and 9
                             Dec 1997 caused data loss and extreme levels.

                    CI MISSING              REPLACED GAPS     QUESTIONABLE      
              YEAR (%) DATA                 OR BAD DATA       FLUCTUATIONS      
              ---- --- -------------------- --------------- --------------------
              1977  69 none                 none            none                
              1978  98 28-30,56-60          none            55-56               
              1979  97 16-24,62-64          none            none                
              1980  91 8-14,142-143,        none            none                
                       167-189                                                  
              1981  94 15-16,49-69          none            none                
              1982  97 66-69,117-119,       none            none                
                       260-264                                                  
              1983  94 26-31,114-117,       none            none                
                       262-264,340-349                                          
              1984  96 12-20,27-31          none            356-366             
              1985 100 none                 none            none                
              1986 100 none                 none            57-58               
              1987  88 2-45                 none            none                
              1988 100 none                 none            none                
              1989 100 none                 none            none                
              1990 100 none                 none            45-47,334           
              1991 100 none                 none            none
              1992 100 none                 none            none
              1993 100 none                 none            none
              1994 100 none                 none            none
              1995 100 none                 none            none
              1996 100 none                 none            none
              1997  94 none                 none            none