Gases database version 2.0 Authors: Roberta Hamme, Steven Emerson, and Jeff Severinghaus Date: April 10, 2007 These databases contain data on dissolved gas measurements published in Hamme, R.C., J.P. Severinghaus (2007) "Dissolved inert gases as tracers of the imbalance between cooling and gas exchange during deep-water formation", Deep-Sea Res. I, in press. Hamme, R.C., S.R. Emerson (2006) "Constraining bubble dynamics and mixing with dissolved gases: Implications for productivity measurements by oxygen mass balance", J. Mar. Res. 64(1), p. 73-95. Hamme, R.C. (2003) "Applications of neon, nitrogen, argon and oxygen to physical, chemical and biological cycles in the ocean", Ph.D. thesis, University of Washington Hamme, R.C., S.R. Emerson (2002) "Mechanisms controlling the global oceanic distribution of the inert gases argon, nitrogen and neon", Geophys. Res. Lett., 29(23), 2120, doi:10.1029/2002GL015273. Several very small corrections have been made to the earlier gas data since 2003, so the numbers will not match Appendix A of Hamme's thesis exactly. This data is provided free for educational and non-profit research purposes. We ask that you acknowledge the authors and appropriate publications in any work that uses this database. Please also send an e- mail to rhamme@uvic.ca, letting us know that you have downloaded the data, so that we can keep you apprised of any further corrections or changes. Both MatLab .mat databases and comma-delimited text files are provided. These two formats contain identical information. NaN = missing data. In particular, Ne samples were not collected at all depths. Also, obvious flyers in both the ONAr and Ne measurements have been removed from the data. Variable naming convention: Databases for three time-series locations are provided, HOT (Hawaii Ocean Time-series at 23oN 158oW), BATS (Bermuda Atlantic Time-series Study at 32oN 64oW) and KNOT (Kyodo North Pacific Ocean Time-series at 44oN 155oE). The HOT data is split into two databases. Data collected in 2000-01 is presented in the HOTgases_2000 database. This data generally includes O2, Ar, N2, Ne measurements. Data collected on HOT cruise 162 (August 2004) is presented in the HOT162gases database. This data includes Ar (by the isotope dilution method, see Hamme and Severinghaus 2007), Kr and Xe measurements. cruisenumber - In the case of HOT and BATS, this is the official cruise number, ie HOT 117-127 or BATS 154. In the case of KNOT, the cruise numbers translate to the official numbers as follows: 1) BO98-22, 2) HO99leg1, 3) HO99leg3, 4) BO99m, 5) MR00-K01, 6) MR00-K03. date - This is the approximate date that samples were collected. In the MatLab database this is in the MatLab datenum format. In the text files it is listed as separate year, month, and date. cast - This is the cast number. For HOT, only data for casts at Station 2 (ALOHA) is provided. For BATS, the shallower casts were taken on a small spatial survey very near the BATS site. For KNOT, casts are not uniformly named due to different naming conventions aboard the different ships. Also, KNOT5 contains some shallow casts which were not collected directly at the KNOT site (14-10, 6-L3, 7-L3). niskin - This is the number of the Niskin bottle that samples were drawn from. depth - Depth in meters. ptmp - Potential temperature in degrees Celsius and referenced to the surface. sal - Salinity expressed on the Practical salinity scale. For HOT and BATS, these are bottle salinities measured at University of Washington where available, and CTD salinities when UW bottle salinity samples were not drawn. For KNOT, these are bottle salinities measured by Japanese collaborators where available, and CTD salinities where bottle salinity samples were not drawn or the data was unavailable. sigma - Potential density of the seawater expressed in sigma units and referenced to the surface. inmixedlayer - 1 = sample was in the mixed layer, 0 = sample was beneath mixed layer Ar - Ar concentration in umol/kg determined from O2/Ar mass spectrometry measurements and O2 titration measurements. For more information on the Ar measurement method see Emerson et al. (1999) "Accurate measurement of O2, N2, and Ar gases in water and the solubility of N2", Marine Chemistry, volume 64, pp. 337-347. For HOT 162, Ar was measured by isotope dilution. See Hamme and Severinghaus (2007) referenced above. Arsat - Supersaturation of Ar in percent. 0% indicates that the Ar concentration is in equilibrium for the potential temperature and salinity of the water. ie. Arsat = (Ar- Areq)/Areq*100 Ar supersaturation is calculated relative to the solubility curve of Hamme, R.C., S.R. Emerson (2004) "The solubility of neon, nitrogen and argon in distilled water and seawater", Deep-Sea Research I, 51(11), p. 1517-1528. N2 - N2 concentration in umol/kg determined from O2/N2 mass spectrometry measurements and O2 titration measurements. For more information on the N2 measurement method see Emerson et al. (1999) "Accurate measurement of O2, N2, and Ar gases in water and the solubility of N2", Marine Chemistry, volume 64, pp. 337-347. N2sat - Supersaturation of N2 in percent. N2 supersaturation is calculated relative to the solubility curve of Hamme, R.C., S.R. Emerson (2004) "The solubility of neon, nitrogen and argon in distilled water and seawater", Deep-Sea Research I, 51(11), p. 1517-1528. Ne - Ne concentration in umol/kg determined by isotope dilution on a quadrupole mass spectrometer. See Hamme, R.C., S.R. Emerson (2004) "Measurement of dissolved neon by isotope dilution using a quadrupole mass spectrometer", Marine Chemistry, 91(1-4), p. 53-64 for more information on the Ne measurement method. Nesat - Supersaturation of Ne in percent. Ne supersaturation is calculated relative to the solubility curve of Hamme, R.C., S.R. Emerson (2004) "The solubility of neon, nitrogen and argon in distilled water and seawater", Deep-Sea Research I, 51(11), p. 1517-1528. O2 - O2 concentration in umol/kg determined from Winkler titration measurements with a visual endpoint. For more information on the O2 measurement method see Emerson et al. (1999) "Accurate measurement of O2, N2, and Ar gases in water and the solubility of N2", Marine Chemistry, volume 64, p. 337-347. O2sat - Supersaturation of O2 in percent. O2 supersaturation is calculated relative to the solubility curve of Garcia and Gordon (1992) "Oxygen solubility in seawater: Better fitting equations", Limnology and Oceanography, 37, p. 1307-1312. Kr - Kr concentration in umol/kg determined by measurement of the Kr/Ar ratio and isotope dilution measurement of the Ar concentration. See Hamme, R.C., J.P. Severinghaus (2007) for more information on the Kr measurement method. Krsat - Supersaturation of Kr in percent. Kr supersaturation is calculated relative to the solubility curve of R.F. Weiss and T.K. Kyser (1978) "Solubility of Krypton in Water and Seawater", Journal of Chemical Thermodynamics, 23(1), 69-72. Xe - Xe concentration in umol/kg determined by measurement of the Xe/Ar ratio and isotope dilution measurement of the Ar concentration. See Hamme, R.C., J.P. Severinghaus (2007) for more information on the Xe measurement method. Xesat - Supersaturation of Xe in percent. Xe supersaturation is calculated relative to a fit to the solubility data of D. Wood and R. Caputi (1966) "Solubilities of Kr and Xe in fresh and sea water", U.S. Naval Radiological Defense Laboratory, Technical Report USNRDL-TR-988, San Francisco, CA, pp. 14. NOTE that the Wood and Caputi Xe solubility data appear to be about 2% too high, so that these Xe saturations are 2% too low. See discussion in Hamme and Severinghaus (2007). N2Ar - N2/Ar ratio determined by mass spectrometry. For more information on the N2/Ar measurement method see Emerson et al. (1999) "Accurate measurement of O2, N2, and Ar gases in water and the solubility of N2", Marine Chemistry, volume 64, p. 337-347. N2Arsat - Supersaturation of N2/Ar ratio. N2/Ar ratio determined by mass spectrometry divided by the equilibrium ratio for the potential temperature and salinity of the water - 1 * 100, ie. N2Arsat = ((N2/Ar) / (N2eq/Areq) - 1) * 100. O2Ar - O2/Ar ratio determined by mass spectrometry. For more information on the O2/Ar measurement method see Emerson et al. (1999) "Accurate measurement of O2, N2, and Ar gases in water and the solubility of N2", Marine Chemistry, volume 64, p. 337-347. O2Arsat - Supersaturation of O2/Ar ratio. O2/Ar ratio determined by mass spectrometry divided by the equilibrium ratio for the potential temperature and salinity of the water - 1 * 100, ie. O2Arsat = ((O2/Ar) / (O2eq/Areq) - 1) * 100. KrArsat - Supersaturation of Kr/Ar ratio. Kr/Ar ratio determined by mass spectrometry divided by the equilibrium ratio for the potential temperature and salinity of the water, ie. KrArsat = ((Kr/Ar) / (Kreq/Areq) - 1) * 100. XeArsat - Supersaturation of Xe/Ar ratio. Xe/Ar ratio determined by mass spectrometry divided by the equilibrium ratio for the potential temperature and salinity of the water, ie. XeArsat = ((Xe/Ar) / (Xeeq/Areq) - 1) * 100.