US JGOFS Antarctic Environments Southern Ocean Process Study (AESOPS) Palmer Leg 96-05, November 1996 Documentation file for: THE HYDROGRAPHIC BOTTLE DATA L.A. Codispoti (lou@ccpo.odu.edu) Old Dominion University, October, 1997 General Comments: This "readme" file pertains to the salinity data taken from sampling bottles with the hydrographic rosette that was equipped with 24 ~10-liter "Niskin-like" Bullister Bottles made mostly of PVC and equipped with orange silicone o-rings during Palmer leg 96-05 (Nov., 1996). Dr. Jack Dymond of Oregon State University was the chief scientist during this leg (jdymond@oce.orst.edu). This cruise was the third AESOPS Leg on the PALMER, and its main purpose was the emplacement of moorings, but a few CTD/hydrocasts were taken. The only hydrographic bottle data reported here were salinity samples that were run on an Autosal salinometer under less than ideal temperature control conditions. After eliminating some questionable values, these bottle salinities appear to be accurate to about 0.004 or better. Some questionable data are not included in this report. These data are retained in files at Old Dominion University and are available upon request. No units are given for salinity in this report because the most recent definitions of salinity define it as a dimensionless number. Methods: The method employed for the bottle salinity data does not differ significantly from the method in the JGOFS protocols that were distributed in 1994 (UNESCO, IOC Manual and Guide #29). Salinities were determined with a Guildline Autosal salinometer. New vials of standard sea-water were used to standardize before and at the end of every run. Agreement between bottle salinities and the recently calibrated sensors on the Sea Bird CTD systems was usually better than 0.015 (except in regions of strong gradients) before post-cruise data processing which employs the bottle salinities to correct the CTD salinities. More information on the quality of the salinity data is given in the companion CTD report. Both the CTD salinity data at the time of bottle tripping and the salinities run on the Niskin bottle samples with an Autosal salinometer are reported here. Temperature: The temperature data associated with each bottle depth were taken by the CTD system during the bottle tripping process. Consult the companion CTD data report for this cruise to learn more about the CTD system. Sampling: Because there is little or no lag time between triggering a bottle and bottle closure with the new SeaBird rosette systems, bottles were generally held at the sampling depth for 30 seconds before tripping. This was not the case at stations 4 and 7 because of sea conditions and proximity to a mooring at station 7. NOTE THAT THE MID-POINT OF THE SAMPLING BOTTLES WAS 0.8 METER ABOVE THE CTD SENSORS. THE DATA HAVE NOT BEEN CORRECTED FOR THIS OFFSET. ALSO NOTE THAT SOME FROZEN NUTRIENT SAMPLES WERE COLLECTED ON THIS LEG, AND SUBSEQUENTLY ANALYZED DURING PALMER LEG 97-01. THESE SAMPLES APPEARED TO SUFFER FROM VARIOUS STORAGE AND LABELING PROBLEMS, SO THEY ARE NOT INCLUDED IN THIS REPORT. If you have guestions about these data, please contact: Dr. L.A. Codispoti CCPO Crittenton Hall Old Dominion University Norfolk, VA 23529 lou@ccpo.odu.edu phone: 757-683-5770 fax: 757-683-5550