Appendix Table 4.  Summaries of Titration Alkalinity Data
                          for Replicate Sea Water Samples

    Tables 4a to 4e summarize the laboratory ALK measurements by potentiometric
titration of replicate samples collected on the five expedition legs of 1991,
presented in the following order:

  Table 4a.   TUNES Leg 1  WOCE Line  P17C
  Table 4b.   TUNES Leg 2  WOCE Lines P17S,P16S
  Table 4c.   TUNES Leg 3  WOCE Line  P16C   
  Table 4d.   Meteor 15    WOCE Line  A9
  Table 4e.   Meteor 18    WOCE Line  A1E

Comments on each column in the table follow:

LEG to SAMPLE   The identifying information for each Niskin bottle sampled at 
STN     DATE    sea.

ANALYSIS        The date of potentiometric titration of an aliquot of sea water
  DATE          taken from a replicate sample bottle. After the aliquot for DIC
                extraction was removed from a bottle, the bottle was  
                immediately resealed and stored at room temperature for short
                periods of time or refrigerated for longer periods of time
                until titration.

TITR            The system used for titration is identified: G, the gravimetric
SYST            system; V, the volumetric system. Sometimes aliquots from the
                same bottle were titrated on both systems.

SAMPLE          The label number for the individual replicate sample bottle
BOTTLE          filled at sea. The prefix "S" indicates a standard 500 ml 
                Corning borosilicate glass bottle with a hollow stopper 
                (individually lapped to the bottle joint with carborundum grit)
                equipped with an aluminum bale type fixture for holding the
                stopper in its sealed position. The prefix "R" indicates a 
                500 ml borosilicate glass bottle equipped with a standard taper 
                (24/40 size) joint and solid stopper with a Rodawiss plastic   
                knurled nut system for holding the stopper. 

TRIAL           This number indicates whether more than one titration was made
                on water from a replicate sample bottle. Sometimes titrations
                were deleted before reaching the data base at all, for example
                if the titration cell was filled improperly. Quite often, one or
                more of multiple trials are flagged in the data set: usually
                multiple trials were made because of a problem with the first 
                trial.

FLAG            The flag code identifies trials that are rejected from further
                consideration due to identifiable experimental reasons. The 
                flags  used have the following meanings: F, evidence indicated 
                that the sample had no mercuric chloride added (see text for 
                further discussion); X, the titrator malfunctioned for some 
                definable reason; EX, a general flag for some other  
                experimental rejection, such as a very poor fit of the  
                titration data.




       Appendix Table 4.  Summaries of Titration Alkalinity Data 
                          for Replicate Sea Water Samples (cont.)

S.I.O           The ALK in micromoles per kilogram of sea water of hydrogen ion 
TRIAL           equivalent is listed for an individual trial titration.

TRIAL           The trial difference for two trials as discussed above, if both
DELTA           trials are unflagged.

BOTTLE          The average bottle ALK for unflagged trials. In most cases 
  ALK           (single trials), the S.I.O. TRIAL and the BOTTLE ALK are 
                identical. 

BOTTLE          The difference in ALK between two bottles collected from a 
 DELTA          single Niskin bottle is listed. 

"NISKIN"        Here is listed the average S.I.O. laboratory ALK result for
   AVG          water from a particular Niskin bottle sampled at sea. If two
                titration systems were used (see TUNES Leg 3, station 222,
                bottle number R4569), the averages for both systems are listed.

{INSTITUTION}   The shipboard ALK result from a shipboard titration. 
   ALK          The institution abbreviations indicate the shipboard CO2 
                analytical group operating on that expedition leg, as follows:
                WHOI, the group of Dr. Catherine Goyet, P.I., of Woods Hole
                Oceanographic Institution, on TUNES Leg 1; CDRG, the group 
                of Dr. Charles Keeling, P.I., of Scripps Institution  of
                Oceanography, on TUNES Leg 3. The TUNES Leg 1 data is considered
                to be final, as reported to the Carbon Dioxide Information and
                Analysis Center. The TUNES Leg 3 data is NOT FINAL pending
                completion of a report in preparation. The remaining legs had no
                shipboard ALK measured by the U.S. CO2 group on board.
                No inference should be made from the listed data as to the 
                imprecision of the data. Here we choose to list data to more
                places than are significant.

{INSTITUTION}   The difference between the shipboard ALK result and the 
 - S.I.O.       average laboratory replicate sample ALK. Note again that for 
                the case discussed above, the differences for both systems are 
                listed.

NOTE:           At the end of the Table 4 section for each leg is a note 
Dilution Factor detailing the multiplicative dilution factor applied to account
                for the addition of the HgCl2 poison solution to the S.I.O. 
                replicate sample bottles. The nominally 500 ml bottles actually
                hold about 585 ml. Thus for the addition of 0.1 ml of saturated
                aqueous HgCl2, a dilution factor of 1.00017 is calculated.
                The shipboard data listed in the last two columns have also 
                been appropriately corrected for dilution by each shipboard
                analysis group.