Batch Number Bottling Date Salinity Total CO2 micromol/kg Total Alkalinity micromol/kg NB Batch 01 Jan 29, 1990 33.508 2020.15 - - Batch 02 Oct 01, 1990 33.363 1978.70 2248.27 A Batch 03 Jan 08, 1991 batch not stable B Batch 04 Mar 20, 1991 batch not stable B Batch 05 May 07, 1991 batch not stable B Batch 06 May 22, 1991 38.43 2304.64 2375.61 A,C Batch 07 Aug 08, 1991 37.12 1926.63 - C,D Batch 08 Aug 26, 1991 batch not stable B Batch 09 Sep 20, 1991 batch not stable B Batch 10 Nov 15, 1991 34.572 1960.61 2257.50 A Batch 11 Jan 07, 1992 38.50 2188.89 - C,D Batch 12 Feb 27, 1992 33.494 1984.26 2226.56 A Batch 13 Jun 25, 1992 32.864 2015.13 2203.79 A Batch 14 Jul 23, 1992 not distributed as RM E Batch 15 Nov 30, 1992 33.199 2031.65 2202.38 A Batch 16 Dec 04, 1992 33.203 2034.54 2206.78 A Batch 17 Apr 08, 1993 33.226 2044.54 2219.15 A Batch 18 Sep 10, 1993 35.298 2115.15 2297.77 A Batch 19 Sep 15, 1993 33.705 2004.08 - D Batch 20 Nov 23, 1993 33.145 1983.40 2211.53 A Batch 21 Jan 28, 1994 34.534 1991.98 2258.36 A Batch 22 Apr 01, 1994 33.561 1995.19 2217.16 A Batch 23 May 04, 1994 33.483 1993.10 2212.71 A Batch 24 Aug 26, 1994 33.264 1987.53 2215.51 A Batch 25 Nov 10, 1994 34.910 2127.21 2299.79 A,F Batch 26 Dec 13, 1994 33.258 1978.34 2176.59 A Batch 27 Dec 21, 1994 33.209 1988.10 2214.89 A Batch 28 Feb 27, 1995 33.407 1994.64 2223.47 A Batch 29 Apr 19, 1995 33.701 1902.33 2184.76 A Batch 30 Jun 14, 1995 33.420 1988.78 2201.88 A Batch 31 Aug 16, 1995 32.899 1876.57 2130.33 A Batch 32 Oct 17, 1995 33.745 1997.57 2221.48 A Batch 33 Feb 27, 1996 33.781 2009.85 2234.92 - Batch 34 Apr 23, 1996 34.514 2061.52 2284.35 - Batch 35 Aug 06, 1996 35.661 2111.62 2354.05 - Batch 36 Nov 07, 1996 35.368 2050.21 2283.83 - Batch 37 Apr 02, 1997 34.983 2044.15 2314.11 - Batch 38 May 08, 1997 34.932 2089.99 2300.89 - Batch 39 Jul 24, 1997 batch not stable B Batch 40 Sep 16, 1997 33.383 1985.76 2196.41 - Batch 41 Oct 31, 1997 33.368 1977.71 2195.78 - Batch 42 Dec 16, 1997 33.364 1985.10 2210.54 - Batch 43 Mar 25, 1998 33.598 1988.64 2202.86 - Batch 44 May 18, 1998 34.271 2030.66 2258.24 - Batch 45 Aug 19, 1998 33.487 1994.17 2204.38 - Batch 46 Oct 27, 1998 33.769 1992.92 2191.27 - Batch 47 Jan 26, 1999 33.716 2006.61 2227.93 - Batch 48 May 14, 1999 33.442 1999.91 2189.62 G Batch 49 Oct 07, 1999 33.935 1991.14 2172.06 G Batch 50 Jan 21, 2000 33.411 2006.21 2211.11 G Batch 51 Jun 08, 2000 34.217 2050.28 2269.86 G Batch 52 Aug 23, 2000 33.608 2005.57 2224.72 G Batch 53 Dec 13, 2000 33.453 2012.03 2222.68 G Batch 54 Apr 20, 2001 35.228 2107.35 2342.09 G Batch 55 May 15, 2001 33.506 2012.06 2227.85 G Batch 56 Sep 14, 2001 33.408 2014.16 2219.69 G,H Batch 57 Nov 29, 2001 33.485 2005.98 2230.33 G Batch 58 Feb 20, 2002 33.487 2010.94 2223.66 G Batch 59 May 3, 2002 33.316 2007.10 2220.98 G Batch 60 Aug 30, 2002 33.012 1991.24 2199.55 G Batch 61 Jun 23, 2003 33.076 1998.17 2202.04 G Batch 62 Aug 21, 2003 35.224 2126.46 2338.20 G Batch 63 Dec 12, 2003 33.369 2016.02 2222.27 G Batch 64 Jan 15, 2004 37.339 2090.89 2427.60 G Batch 65 Feb 20, 2004 33.049 1993.68 2206.00 G Batch 66 Jul 23, 2004 32.962 1969.57 2193.27 G Batch 67 Oct 15, 2004 34.411 1983.75 2258.27 G Batch 68 Dec 10, 2004 33.758 2003.78 2233.71 G Batch 69 Jan 4, 2005 31.569 1907.63 2114.42 G Batch 70 Apr 27, 2005 33.016 1989.53 2160.46 G Batch 71 May 19, 2005 33.923 2032.84 2254.50 G Batch 72 Jul 27, 2005 35.015 2091.61 2312.79 G Batch 73 Nov 17, 2005 34.523 2057.30 2253.50 G Batch 74 Dec 15, 2005 34.739 2085.53 2305.34 G Batch 75 Mar 2, 2006 33.222 2005.98 2210.09 G Batch 76 May 18, 2006 34.835 2101.69 2314.49 G Batch 77 July 13, 2006 33.129 1998.44 2199.33 G Batch 78 September 21, 2006 33.285 1991.93 2185.57 G Batch 79 November 21, 2006 34.236 2038.63 2262.31 G Batch 80 January 9, 2007 33.357 2006.50 2214.49 G Batch 81 April 26, 2007 33.378 2011.49 2201.20 G Batch 82 June 28, 2007 35.356 2118.25 2335.02 G Batch 83 July 26, 2007 34.611 2055.57 2286.34 G Batch 84 September 6, 2007 33.391 2001.23 2201.01 G Batch 85 October 12, 2007 33.326 2000.44 2184.03 G Batch 86 December 20, 2007 33.097 1988.37 2175.56 G Batch 87 April 15, 2008 33.191 2012.01 2201.16 G Batch 88 June 5, 2008 33.328 2013.42 2205.41 G

(A) Total alkalinity was not measured when the batch was originally certified; the total alkalinity value is based on measurements performed on archived samples of the batch.

(B) The measured values of total dissolved inorganic carbon and of total alkalinity changed with time, probably due to the effects of microbial growth in the bottles. This batch was not certified as reference materials.

(C) This batch was a synthetic solution of sodium bicarbonate in sodium chloride prepared directly in the holding tank by diluting concentrated, filtered solutions of the two salts with deionized (Milli-Q®) water. The salinity value was assigned so as to allow the correct density at 20^oC to be calculated using the density-salinity relationship for sea water.

(D) Total alkalinity was not measured as archived samples were not available; value is expected to have been stable.

(E) This batch was used as a basis of a collaborative study for the analysis of total dissolved inorganic carbon by coulometry.

(F) This batch was prepared in England by using North Atlantic near surface water. All analyses were performed, as with all previous batches, in the laboratories of Andrew G. Dickson and Charles D. Keeling.

(G) This batch was certified for total dissolved inorganic carbon using a Ruska electronic constant-volume manometer rather than the mercury column manometer for Batches 1 - 47.

(H) This batch was used in a collaborative study involving the analysis of CO₂ in air from glass ampoules.