                NH0307A                 
GLOBEC cruise on the New Horizon, July 2-8

 All Stations except 1 and 34: Use primary sensor pair 
 with no correction. Stations 1 and 34: use secondary sensor
 pair with a correction:
    Ccorr = C * 1.00009930

Use ~/lib/binav2c2.nh0307a.f or ...s2.f for *c files. 
Data has tr, fl, ox. Transmissometer has a correction,
Oxygen has a correction in the SeaBird configuration file:
 SOC and Voffset were recomputed using the Winkler sample 
 results. Alignctd used a 5 second delay for oxygen.

  Trans = SN-CST-492DR, factory cal 30 Aug 01 (Scripp's)
   Two atsea aircals were done, but used the first one since
        the second one had a note in the log book that there was 
        a lot of salt spray and it read high. 
        Note this transmissometer 
        uses a different formula to determine % light transmission.
        Used SeaBird's recommended method to determing slope and
        offset values for transmissometer. (Application Note #07, Aug.01rev.)
      trn = (20.4296 * trn) - 1.1475

August 14, 2003
 
nh0307a CTD Calibration

    During cruise nh0307a a total of 37 CTD stations were completed, 
with Scripps' CTD #0675. The pressure sensor, s/n 88907, was calibrated 
on July 12, 2003. Stations were completed along the Newport, Five Mile,
Crescent City, and Heceta Head Hydro lines
(NH-1 to NH-85 on 3-4 July, CR-1 to CR-11 on 4-5 July, FM-9 to FM-1
on 6 July, HH-7 to HH-5 on 7 July, and on a 2nd leg: HH-1 to HH-4 on 8 July), 
with a maximum sampling depth of 1005m.
  
   The seabird CTD was attached to a rosette and at most 
stations 12 10-liter Niskin bottles were fired. Most of the bottles 
were for Pat Wheeler's biological analysis  with 1 bottle 
reserved specifically for the ctd calibration. At most stations 1 
or 2 of the biologist's sample depths also coincided with a 
reasonable mixed area for a salinity sample, and duplicate 
salt samples were drawn from 1-3 Niskin bottles at each station. 
All of the salinity samples were run on Autosal (#6) 
back in the lab in Corvallis. Five points were edited out of 
both sensor's data that had large differences (>2 std. dev.)
A final comparison of the bottle and CTD conductivity was made.
  The results of the run was as follows:

 Bottle salinity - CTD PRIMARY sensor pair (T0=2166, C0=1879
                                        Cal:12Jun03(by SIO),23May03(by SB)
 
 All means and std. dev. are in mmhos/cm2.

First Run:
      N       Mean      Std Dev     Mean    Std Dev
               C1         C1         S1       S1
     69     -0.008       0.077     -0.009    0.084
After editing out 5 points:
      N       Mean      Std Dev     Mean    Std Dev
               C1         C1         S1       S1
     64      0.001       0.002      0.001    0.002

 Bottle salinity - CTD SECONDARY sensor pair (T1=2165,C1=2569
                                        Cal:12Jun03(by SIO), 23May03(by SB)

First Run: 
      N       Mean      Std Dev     Mean    Std Dev
               C1         C1         S1       S1
     69     -0.006       0.077     -0.006    0.084
After editing out 5 points:
      N       Mean      Std Dev     Mean    Std Dev
               C1         C1         S1       S1
     64      0.003       0.002      0.004    0.002


CONCLUSION: Results of the comparison between in situ sample data and 
the CTD output are summarized above. The sample conductivity was 
calculated using the CTD  temperature and sample salinity. The analysis 
of the nh0307a sample and CTD conductivity differences showed 
corrections were needed for the secondary sensor pair. The conductivity 
differences had means of 0.001 (primary sensor), and 0.003 
(secondary sensor); and standard deviations of 0.002 and 0.002 
respectively. 
  The primary sensor pair correction had no correction,
  and the secondary pair correction is:
   Ccorr = C * 1.00009930
     The primary sensor pair was the sensor pair used for 
final processing for all casts except Stations 1 and 34 which
had areas of minor clogging in pair 1.
