WHP CRUISE SUMMARY INFORMATION WOCE section designation A17 Expedition designation (EXPOCODE) 3230CITHER2_1-2 Chief Scientist(s) and their affiliation Laurent Mémery, LODYC Dates 1994.01.04 - 1994.02.13 1994.02.17 - 1994.03.21 Ship M. EWING Ports of call Montevideo, Uruguay to Falklands Islands to Salvador de Bahia, Brazil to Cayenne to Fort de France Number of stations 117 (leg 1), 118 (leg 2) Geographic boundaries of the stations 13°39.74''N 57°13.62''W 29°59.98''W 50°42.31''S Floats and drifters deployed none Moorings deployed or recovered none Contributing Authors none listed WFP Ref. No.: A17 Updated: 19 November 1996 CRUISE REPORT A17 section (CITHER 2: CIrculation THERmohaline) Ship: Maurice Ewing Chief Scientist: Laurent Mémery Laboratoire d'Océanographie Dynamique et de Climatologie (LODYC) Université Pierre et Marie Curie, Case 100, 4 Place Jussieu 75252 Paris Cedex 5 Tel: 01 44 27 49 66 Fax: 0144 27 7158 email: memery@lodyc.jussieu.fr Leg 1 Ports: Montevideo (Uruguay) - Falklands Islands - Salvador de Bahia (Brazil) Date: Jan. 4 - Feb. 13, 1994 117 small volume stations (no large volume) Chief scientist: Laurent Mémery CTDO2: Michel Arhan (LPO/Brest/France) ADCP: Michel Arhan (LPO/Brest/France) Nutrients, pH, alkalinity, phytoplankton, DOC: Aida Rios (IIM/Vigo/Spain) Total carbon: Linda Bingler (MSL, Sequim, WA, USA) CFCs: Laurent Mémery (LODYC/Paris, France) Tritium - Helium: Philippe Jean Baptiste (LMCE/Gif/France) Leg 2 Ports: Salvador de Bahia - Cayenne - Fort de France Date: Feb. 17- Mar. 21, 1994 118 small volume stations (no large volume) Chief Scientist: Laurent Mémery CTDO2: Herlé Mercier (LPO/Brest/France) ADCP: Herlé Mercier (LPO/Brest/France) Nutrients, pH, alkalinity, phytoplankton, DOC: Aida Rios (IIM/Vigo/Spain) Total carbon: Linda Bingler (MSL, Sequim, WA, USA) CFCs: Laurent Mémery (LODYC/Paris, France) Tritium - Helium: Philippe Jean Baptiste (LMCE/Gif/France) CITHER 2 (A17) is part of the French component of WOCE focused on the South Atlantic Ocean (CITHER 1: WHP A6 - A7 in 1993 and CITHER 3: WHP A13 - A14 in 1995). The track has been elaborated taking into account several basic principles: - optimal description of all the water masses and of their meridional evolution between 50°S and 10°N. - definition of the western boundary conditions of the South Atlantic Ocean. - resolution of the western boundary currents and definition of closed "boxes" in order to be able to use conservation constrains - horizontal (30nm) and vertical (32 bottles) coverage in agreement with the WOCE recommendations, with increased horizontal resolution (down to several nm) on the western boundary sections. During the cruise, 235 hydrographic stations with complete CTDO2 profiles using a rosette of 32 bottles (8 liters) have been performed. Measurements of salinity, oxygen, nutrients, pH and CFCs have been made at every station. Alkalinity and total dissolved inorganic carbon have been measured one every third station along the main section, and one every other station for the 4 western boundary sections. At every station, at the surface, alkalinity has been measured, and a sample for phytoplankton measurements has been taken. The data set has been completed by 10 stations sampled in dissolved organic carbon (DOC) on the main section from the Falkland Islands to 10°N. Finally, 30 stations have been sampled in Tritium, with 20 stations in Helium 3 as well, with a strong emphasis on the western boundaries. Moreover, deep SF6 samples on 7 stations have been taken in the Brazil Basin and sent to Woods Hole. These samples will give the background level of SF6 before a tracer release experiment is done in the framework of Deep Basin Experiment. During most of the cruise, the Hydrosweep central beam has been used to get the bottom depth, and direct current profiles have been obtained with the ADCP. Figures 1a and 1b show the track of the two legs of the cruise and tables 1a, 1b the position of the stations (see text for more explanations). First leg (fig. 1a). - Jan. 4: departure from Montevideo (point A) towards East South East to get 50 liters of nutrient free surface waters needed for nutrient measurements, before going South (where there is no such nutrient free waters). - Jan. 5: direction Argentina basin towards bottom depths larger than 6000m to test and wind the wire. Two test-stations in between. - Jan. 8: direction Falklands Islands for the beginning of the main section. - Jan. 10: beginning of the main South - North section by a "western" boundary sub section between the Falklands plateau (point B) and the abyssal plain of the Argentina basin. Closed station (down to 5nm) according to the topography. - Jan. 12: end the Falklands western boundary section and beginning of the "regular" section (spacing between stations = 30nm). - Jan. 14 -15: strong depression arriving during station 23. Work stopped during a day. - Jan. 21: after station 41 (point C), direction towards Brazil (North - West: point D). - Jan. 23: beginning of the Porto Alegre western boundary section towards East, with closed stations according to the bathymetry (line D-C). - Jan. 26: end of the western boundary section (station 59) and new very strong depression. After major problems with the wire and the rosette, nothing done during almost two days. - Jan. 31: station 72 at the Vema channel, between the Argentina basin and the Brazil basin. Because of the delay due to the two depressions, spacing between stations not decreased and kept at 30nm. - Feb. 5 - 6: several "closed" stations (20nm) near the Martin Vaz islands (very variable topography: point E). - Feb. 10: station 115 (point F), last point before transit to Salvador de Bahia. Test stations 116 (at 3000m for CFCs blanks) and 117 at the same position. - Feb. 13: arrival at Salvador de Bahia (point G). End of the first leg. Second leg (fig. 1b). - Feb. 17: departure from Salvador de Bahia (after 4 days of Carnival!) and beginning of the Salvador western boundary section, with very closed stations (line H-I). - Feb. 21: after many problems with the rosette, end of the western boundary section two days late on the schedule (point F). Because of the problems, decision to stop in Recife (point I) to pick up a colleague coming from France. - Feb. 24: last station (149) before transit to Recife. - Feb. 26: back to station 150 to continue the main North South section. - Feb. 28: at sta. 153, the first 500m of the wire are cut, because of a bad reception of the CTD signal, which is getting worst and worst. After that operation, no more problems until the end of the cruise. - March 14: end of the main North - South section at station 210 (point K). - March 15: beginning of the last section between the Mid Atlantic Ridge and Cayenne (line L-K-M-N). - March 20: last station in front of Cayenne (station 235: point N). - March 21: end of the CITHER 2 cruise; beginning of the transit towards Fort de France (Martinique). ACKNOWLEDGMENTS Despite some problems encountered during that cruise (weather, wire, ...), CITHER 2 has been a total success. All the objectives of the program have been reached in terms of spatial coverage, types of measurements and data quality. Obviously, those results should have not been obtained without the very efficient help and the availability of every member of the crew. The work has always been done in a very constructive and nice atmosphere. Moreover, some work on the ship was needed before the beginning of the cruise (concerning the CTD lab or the electrical alimentation). Everything was done when we arrived at Montevideo, and without those modifications, the cruise would have been much more difficult: we thank the technical team who has done that very useful work. During the first leg, the role of the captain Ian Young and of the first mate Louis Mello were crucial. Moreover, the science officer Bruce Francis (and his team) must be more specifically thanked. He has made a fantastic job during the whole cruise: with kindness and efficiency, he has always been present to help us as soon as we were facing a problem. Finally, that program could not have been possible without Michael Rawson, who has received us when the "Maurice Ewing" was in Florida to understand our needs and make the modifications needed on the ship, and who has been obliged to deal with extremely difficult administrative problems. CITHER 2 CRUISE SCIENTISTS First and Second Leg NAME FUNCTION AFFILIATION J. ALVAREZ SALGADO Nutrients IIM, Vigo, Spain L. ARLEN TCO2 NOAA/NMFS, Highlands, NJ, USA L. BINGLER TCO2 Battelle, Sequim, Wash., USA S. CHIHAOUI CFCs LODYC, Paris, France A. FERNANDEZ RIOS Alk, pH IIM, Vigo, Spain J. A. FONTAINHA Brazilian Obs. Rio, Brazil C. GONZALES Nutrients IIM, Vigo, Spain J. P. GOUILLOU CTD LPO, Brest, France L. MÉMERY Ch. Sci., CFCs LODYC, Paris, France M. J. MESSIAS CFCs LODYC, Paris, France G. ROSON PORTO Alk, pH IIM, Vigo, Spain First Leg M. ARHAN CTD LPO, Brest, France J. BALLE CTD LODYC, Paris. France P. BRANELLEC S, O2 LPO, Brest. France P. CHANTRY CTD LODYC, Paris, France E. CHARTIER O2 LPO, Brest, France N. DANIAULT CTD LPO, Brest, France J. C. DUTAY Tritium, S LMCE, Gif/Yvette, France M. FICHAUT CTD IFREMER, Brest, France C. HEMON CTD LPO, Brest, France P. LE BOT S LPO, Brest, France H. LOUKOS CTD LODYC, Paris, France G. MADEC CTD LODYC, Paris, France Second Leg A. BILLANT S, O2 LPO, Brest. France E. BRAGA O2 USP, São Paulo, Brazil S. DELEVILLE CTD LODYC, Paris, France J. P. GIRARDOT CTD LPO, Brest, France Y. GOURIOU CTD ORSTOM, Brest, France A. LAZAR CTD LODYC, Paris. France C. LEVY CTD LODYC, Paris, France M. LEVY CTD, CFCs LODYC, Paris, France O. MARTI Tritium, S LMCE, Gif/Yvette, France G. MAUDIRE CTD IFREMER, Brest, France H. MERCIER CTD LPO, Brest. France O. PEDEN CTD LPO, Brest, France J. PEDREIRA S LPO, Brest, France Table 1a: CITHER II - Leg 1 ALL STATIONS STAT. DATE TIME (GMT) LATITUDE LONGITUDE DEPTH NO. OF BOTTLES NO. 001 08/01/1994 19:58:08 S 46 49 W 053 42 6041 32 002 09/01/1994 16:16:50 S 49 35 W 056 10 0702 32 003 10/01/1994 00:43:42 S 50 42 W 057 13 0235 32 004 10/01/1994 04:38:40 S 50 17 W 056 47 0449 32 005 10/01/1994 08:58:16 S 49 51 W 056 21 0589 12 006 10/01/1994 13:06:53 S 49 26 W 055 56 0770 32 007 10/01/1994 17:19:19 S 49 01 W 055 31 1082 16 008 10/01/1994 21:00:51 S 48 40 W 055 11 1737 18 009 11/01/1994 00:19:29 S 48 30 W 055 02 2883 24 010 11/01/1994 05:01:44 S 48 27 W 054 58 4205 29 011 11/01/1994 11:14:15 S 48 15 W 054 47 5007 31 012 11/01/1994 17:16:49 S 48 06 W 054 38 5575 32 013 12/01/1994 00:04:31 S 47 41 W 054 14 5817 32 014 12/01/1994 07:24:25 S 47 16 W 053 52 6014 32 015 12/01/1994 14:14:51 S 46 51 W 053 32 6068 32 016 12/01/1994 21:34:31 S 46 25 W 053 09 6088 32 017 13/01/1994 04:41:45 S 46 00 W 052 48 6072 32 018 13/01/1994 12:03:56 S 45 35 W 052 27 6031 32 019 13/01/1994 19:39:26 S 45 10 W 052 05 6012 32 020 14/01/1994 03:11:31 S 44 46 W 051 45 5889 32 021 14/01/1994 11:24:06 S 44 20 W 051 21 5752 32 022 14/01/1994 19:08:38 S 43 55 W 051 00 5568 32 023 15/01/1994 23:08:13 S 43 29 W 050 39 5397 32 024 16/01/1994 07:35:05 S 43 05 W 050 18 5525 32 025 16/01/1994 14:07:34 S 42 40 W 049 57 5683 32 026 16/01/1994 20:58:05 S 42 16 W 049 35 5809 32 027 17/01/1994 04:05:00 S 41 50 W 049 14 5749 32 028 17/01/1994 11:07:40 S 41 25 W 048 53 5574 32 029 17/01/1994 18:15:42 S 41 00 W 048 31 5443 32 030 18/01/1994 01:17:30 S 40 35 W 048 10 5340 32 031 18/01/1994 07:55:21 S 40 10 W 047 48 5293 32 032 18/01/1994 14:13:56 S 39 45 W 047 27 5269 32 033 18/01/1994 20:50:28 S 39 20 W 047 06 5238 32 034 19/01/1994 03:31:44 S 38 55 W 046 44 5207 32 035 19/01/1994 10:36:07 S 38 30 W 046 22 5190 32 036 19/01/1994 17:34:04 S 38 05 W 046 01 5172 32 037 20/01/1994 00:14:40 S 37 40 W 045 39 5156 32 038 20/01/1994 07:14:08 S 37 15 W 045 19 5114 32 039 20/01/1994 13:44:14 S 36 50 W 044 57 5057 32 040 20/01/1994 19:54:57 S 36 25 W 044 36 4984 32 041 21/01/1994 02:00:01 S 36 00 W 044 15 4905 32 042 21/01/1994 10:04:10 S 35 30 W 045 03 4841 32 043 22/01/1994 17:13:50 S 32 21 W 050 13 0234 09 044 22/01/1994 18:38:32 S 32 25 W 050 06 0972 16 045 22/01/1994 21:43:16 S 32 36 W 049 46 1505 18 046 23/01/1994 01:07:21 S 32 48 W 049 27 1748 19 047 23/01/1994 04:52:06 S 33 00 W 049 07 2570 23 048 23/01/1994 09:00:58 S 33 12 W 048 48 3023 27 049 23/01/1994 13:02:18 S 33 24 W 048 28 3204 27 050 23/01/1994 17:57:48 S 33 36 W 048 09 3358 27 051 23/01/1994 22:20:34 S 33 48 W 047 51 3779 30 052 24/01/1994 03:50:28 S 34 04 W 047 23 4210 32 053 24/01/1994 10:22:58 S 34 21 W 046 56 4500 32 054 24/01/1994 18:59:24 S 34 37 W 046 29 4651 32 055 25/01/1994 00:46:47 S 34 53 W 046 02 4742 32 056 25/01/1994 06:44:13 S 35 10 W 045 35 4797 32 057 25/01/1994 12:52:45 S 35 26 W 045 08 4862 32 058 25/01/1994 19:25:29 S 35 43 W 044 42 4838 32 059 26/01/1994 14:14:16 S 36 00 W 044 14 4886 32 060 27/01/1994 23:05:27 S 35 35 W 043 53 4893 32 061 28/01/1994 05:29:16 S 35 12 W 043 33 4878 32 062 28/01/1994 11:55:11 S 34 49 W 043 12 4791 32 063 28/01/1994 18:04:30 S 34 25 W 042 51 4651 32 064 28/01/1994 23:52:54 S 34 01 W 042 30 4535 32 065 29/01/1994 05:47:46 S 33 37 W 042 09 4529 32 066 29/01/1994 11:33:33 S 33 14 W 041 48 4570 30 067 29/01/1994 18:06:06 S 32 50 W 041 27 4510 31 068 29/01/1994 23:55:25 S 32 27 W 041 06 4422 31 069 30/01/1994 06:13:28 S 32 03 W 040 46 4112 28 070 30/01/1994 12:03:37 S 31 40 W 040 25 3753 29 071 30/01/1994 17:41:14 S 31 16 W 040 04 3628 27 072 30/01/1994 23:03:25 S 30 53 W 039 44 4414 31 073 31/01/1994 05:06:23 S 30 29 W 039 22 4150 29 074 31/01/1994 10:24:56 S 30 05 W 039 02 4220 30 075 31/01/1994 15:51:03 S 29 42 W 038 41 4293 30 076 31/01/1994 21:14:56 S 29 18 W 038 20 4315 30 077 01/02/1994 03:06:15 S 28 54 W 037 59 4407 31 078 01/02/1994 08:57:27 S 28 31 W 037 38 4450 31 079 01/02/1994 14:40:43 S 28 07 W 037 18 4529 32 080 01/02/1994 20:15:02 S 27 44 W 036 57 4678 32 081 02/02/1994 01:58:07 S 27 21 W 036 36 5022 32 082 02/02/1994 07:52:06 S 26 58 W 036 16 4605 32 083 02/02/1994 13:55:17 S 26 34 W 035 55 4484 32 084 02/02/1994 19:49:22 S 26 11 W 035 34 4253 31 085 03/02/1994 01:26:41 S 25 47 W 035 14 4278 31 086 03/02/1994 07:18:26 S 25 24 W 034 53 4401 32 087 03/02/1994 13:02:39 S 25 01 W 034 32 4545 32 088 03/02/1994 18:51:40 S 24 37 W 034 11 4625 32 089 04/02/1994 00:40:19 S 24 14 W 033 51 4583 32 090 04/02/1994 06:32:12 S 23 50 W 033 30 4627 32 091 04/02/1994 12:20:20 S 23 27 W 033 10 4754 32 092 04/02/1994 18:24:38 S 23 04 W 032 49 4783 32 093 05/02/1994 00:14:23 S 22 40 W 032 28 4598 32 094 05/02/1994 05:57:09 S 22 17 W 032 08 4559 32 095 05/02/1994 16:35:29 S 21 54 W 031 47 4550 32 096 05/02/1994 22:35:39 S 21 31 W 031 27 4614 32 097 06/02/1994 03:36:59 S 21 15 W 031 13 4632 32 098 06/02/1994 08:34:02 S 21 00 W 030 59 4651 32 099 06/02/1994 13:40:30 S 20 39 W 030 58 4545 32 100 06/02/1994 18:38:59 S 20 20 W 030 57 4499 32 101 06/02/1994 23:34:17 S 20 00 W 030 56 4552 32 102 07/02/1994 04:38:51 S 19 39 W 030 55 4548 32 103 07/02/1994 09:30:40 S 19 20 W 030 54 4530 32 104 07/02/1994 15:23:03 S 18 50 W 030 52 4507 32 105 07/02/1994 21:13:59 S 18 21 W 030 51 4582 32 106 08/02/1994 03:10:42 S 17 51 W 030 49 4763 32 107 08/02/1994 09:13:28 S 17 22 W 030 48 4874 32 108 08/02/1994 15:17:44 S 16 52 W 030 46 4933 32 109 08/02/1994 21:19:35 S 16 23 W 030 44 4930 32 110 09/02/1994 03:55:33 S 15 53 W 030 43 4927 32 111 09/02/1994 09:59:44 S 15 24 W 030 41 4825 32 112 09/02/1994 16:16:42 S 14 54 W 030 40 4871 32 113 09/02/1994 22:20:54 S 14 25 W 030 38 4904 32 114 10/02/1994 04:26:11 S 13 55 W 030 36 5312 32 115 10/02/1994 10:29:00 S 13 26 W 030 35 5199 32 116 10/02/1994 18:40:06 S 13 26 W 030 35 5205 32 117 11/02/1994 00:19:47 S 13 26 W 030 35 5205 32 Table 1b: CITHER II - Leg 2 ALL STATIONS STAT. DATE TIME (GMT) LATITUDE LONGITUDE DEPTH NO. OF BOTTLES NO. 118 17/02/1994 23:24:32 S 12 21 W 037 37 0319 16 119 18/02/1994 01:54:33 S 12 23 W 037 35 1025 16 120 18/02/1994 04:49:47 S 12 24 W 037 34 1568 16 121 18/02/1994 17:46:50 S 12 25 W 037 32 1996 32 122 18/02/1994 12:21:48 S 12 29 W 037 27 2503 32 123 18/02/1994 18:17:37 S 12 34 W 037 20 3017 32 124 19/02/1994 00:15:56 S 12 42 W 037 07 3519 32 125 19/02/1994 05:40:49 S 12 57 W 036 47 3869 32 126 19/02/1994 11:47:13 S 13 12 W 036 27 4196 32 127 19/02/1994 17:49:25 S 13 13 W 035 57 4339 32 128 20/02/1994 00:02:01 S 13 14 W 035 28 4406 32 129 20/02/1994 07:20:50 S 13 15 W 034 59 4433 32 130 20/02/1994 14:17:39 S 13 16 W 034 30 4519 32 131 20/02/1994 18:35:47 S 13 16 W 034 29 4516 32 132 20/02/1994 23:17:00 S 13 18 W 034 00 3751 32 133 21/02/1994 04:57:18 S 13 19 W 033 31 4587 32 134 21/02/1994 10:24:42 S 13 19 W 033 31 4588 16 135 21/02/1994 14:35:01 S 13 20 W 033 01 4561 32 136 21/02/1994 20:47:39 S 13 21 W 032 32 4645 32 137 22/02/1994 01:08:58 S 13 21 W 032 32 4645 16 138 22/02/1994 05:40:41 S 13 22 W 032 03 4842 32 139 22/02/1994 10:30:05 S 13 22 W 032 03 4838 16 140 22/02/1994 16:38:32 S 13 24 W 031 34 4985 32 141 22/02/1994 23:08:08 S 13 25 W 031 04 5043 32 142 23/02/1994 05:42:40 S 13 26 W 030 35 5165 32 143 23/02/1994 12:10:25 S 12 56 W 030 33 5138 32 144 23/02/1994 18:29:53 S 12 26 W 030 32 5334 32 145 24/02/1994 01:04:00 S 11 56 W 030 30 5397 32 146 24/02/1994 07:37:49 S 11 26 W 030 29 5360 32 147 24/02/1994 14:06:14 S 10 57 W 030 27 5331 32 148 24/02/1994 20:40:34 S 10 27 W 030 25 5313 32 149 25/02/1994 03:35:19 S 09 57 W 030 24 5298 32 150 25/02/1994 10:04:25 S 09 27 W 030 22 5306 32 151 27/02/1994 22:33:50 S 08 57 W 030 21 5242 32 152 28/02/1994 04:46:52 S 08 28 W 030 19 5366 32 153 28/02/1994 10:58:54 S 07 58 W 030 17 5388 32 154 28/02/1994 17:58:10 S 07 28 W 030 16 5387 32 155 01/03/1994 00:25:03 S 06 58 W 030 14 5369 32 156 01/03/1994 06:44:06 S 06 28 W 030 13 5209 32 157 01/03/1994 12:56:25 S 05 59 W 030 11 5179 32 158 01/03/1994 19:18:22 S 05 29 W 030 09 5106 32 159 02/03/1994 01:34:05 S 04 59 W 030 08 4972 32 160 02/03/1994 08:00:12 S 04 29 W 030 06 4680 32 161 02/03/1994 13:58:31 S 03 59 W 030 05 4883 32 162 02/03/1994 20:08:30 S 03 30 W 030 03 4828 32 163 03/03/1994 02:06:26 S 03 00 W 030 01 4888 32 164 03/03/1994 08:17:24 S 02 29 W 030 00 4878 32 165 03/03/1994 13:19:39 S 02 12 W 029 59 4883 32 166 03/03/1994 18:21:34 S 01 54 W 030 00 4914 32 167 03/03/1994 23:26:36 S 01 35 W 030 00 4964 32 168 04/03/1994 04:25:59 S 01 18 W 029 59 4224 32 169 04/03/1994 09:13:20 S 00 59 W 030 00 3858 32 170 04/03/1994 14:30:27 S 00 44 W 030 25 4492 32 171 04/03/1994 18:37:09 S 00 45 W 030 25 4496 32 172 04/03/1994 22:35:48 S 00 30 W 030 51 4107 32 173 05/03/1994 04:07:01 S 00 14 W 031 17 4289 32 174 05/03/1994 09:39:18 N 00 00 W 031 43 4224 32 175 05/03/1994 15:33:30 N 00 14 W 032 09 4555 32 176 05/03/1994 21:18:43 N 00 29 W 032 34 4566 32 177 06/03/1994 03:03:58 N 00 44 W 033 00 3524 32 178 06/03/1994 08:26:52 N 00 59 W 033 26 3717 32 179 06/03/1994 14:20:42 N 01 17 W 033 56 4028 32 180 06/03/1994 20:23:07 N 01 35 W 034 26 3904 32 181 07/03/1994 02:11:13 N 01 52 W 034 56 4000 32 182 07/03/1994 08:09:39 N 02 10 W 035 26 4303 32 183 07/03/1994 14:19:26 N 02 27 W 035 56 3690 32 184 07/03/1994 20:02:29 N 02 45 W 036 27 4324 32 185 08/03/1994 02:11:20 N 03 02 W 036 57 4146 32 186 08/03/1994 08:17:02 N 03 19 W 037 27 4546 32 187 08/03/1994 14:30:54 N 03 37 W 037 57 4372 32 188 08/03/1994 20:43:36 N 03 54 W 038 27 4349 32 189 09/03/1994 02:51:52 N 04 12 W 038 57 4593 32 190 09/03/1994 09:01:46 N 04 29 W 039 27 4433 32 191 09/03/1994 15:03:53 N 04 47 W 039 58 4466 32 192 09/03/1994 21:14:23 N 05 04 W 040 28 4666 32 193 10/03/1994 03:35:49 N 05 22 W 040 58 4663 32 194 10/03/1994 08:09:15 N 05 22 W 040 58 4655 32 195 10/03/1994 12:40:59 N 05 39 W 041 28 4696 32 196 10/03/1994 18:55:03 N 05 57 W 041 59 4707 32 197 11/03/1994 01:11:43 N 06 15 W 042 29 4707 32 198 11/03/1994 07:20:13 N 06 32 W 042 59 4633 32 199 11/03/1994 13:32:25 N 06 49 W 043 29 4661 32 200 11/03/1994 19:47:28 N 07 07 W 044 00 46S 6 32 201 12/03/1994 02:03:21 N 07 24 W 044 30 4566 32 202 12/03/1994 08:20:58 N 07 42 W 045 00 4542 32 203 12/03/1994 15:01:06 N 08 00 W 045 31 4537 32 204 12/03/1994 21:18:10 N 08 17 W 046 01 4571 32 205 13/03/1994 03:58:14 N 08 35 W 046 31 4602 32 206 13/03/1994 10:21:06 N 08 52 W 047 02 4654 32 207 13/03/1994 16:33:32 N 09 09 W 047 33 4691 32 206 13/03/1994 22:36:27 N 09 27 W 048 03 4741 32 209 14/03/1994 04:48:07 N 09 45 W 048 34 4780 32 210 14/03/1994 10:51:06 N 10 02 W 049 04 4851 32 211 15/03/1994 11:19:10 N 13 12 W 047 13 4285 32 212 15/03/1994 16:37:03 N 13 39 W 046 57 3843 32 213 15/03/1994 22:09:02 N 13 12 W 047 13 4191 32 214 16/03/1994 03:59:18 N 12 45 W 047 29 4133 32 215 16/03/1994 09:35:39 N 12 18 W 047 45 4519 32 216 16/03/1994 15:28:10 N 11 51 W 048 01 4640 32 217 16/03/1994 21:13:10 N 11 24 W 048 17 4935 32 218 17/03/1994 03:25:31 N 10 56 W 048 32 4914 32 219 17/03/1994 09:25:15 N 10 29 W 048 49 4891 32 220 17/03/1994 15:16:02 N 10 02 W 049 04 4847 32 221 17/03/1994 21:10:29 N 09 36 W 049 19 4768 32 222 18/03/1994 03:06:39 N 09 10 W 049 35 4679 32 223 18/03/1994 08:58:30 N 08 44 W 049 50 4560 32 224 18/03/1994 14:35:21 N 08 18 W 050 05 4471 32 225 18/03/1994 20:24:50 N 07 52 W 050 20 4387 32 226 19/03/1994 02:40:02 N 07 26 W 050 34 4278 32 227 19/03/1994 08:37:21 N 07 00 W 050 50 4069 32 228 19/03/1994 14:31:41 N 06 34 W 051 05 3529 32 229 19/03/1994 18:54:35 N 06 19 W 051 14 2991 32 230 19/03/1994 23:22:48 N 06 09 W 051 21 2773 32 231 20/03/1994 04:03:04 N 06 01 W 051 24 2149 32 232 20/03/1994 07:21:47 N 05 57 W 051 26 1529 32 233 20/03/1994 10:16:53 N 05 55 W 051 28 0992 32 234 20/03/1994 12:42:36 N 05 53 W 051 28 0494 32 235 20/03/1994 16:13:03 N 05 53 W 051 30 0243 32 Fig.1a: EW9401 Montevideo - Salvador Jan 4 - Feb 13 1994* Fig.1b: EW - 9402 NAVIGATION TRACK LINE; SCALE = 0.3 inch/deg.* Figures shown in pdf file. -------------------------------------------------------------------------------- WOCE A17 DQE Notes: Dissolved Oxygen and Nutrients Joe C. Jennings, Jr. and Louis I. Gordon Overall impressions: The WOCE A17 section was comprised of two legs and roughly parallels the coastline of eastern South America from just north of the Falkland/Malvinas Islands to a point northwest of the mouth of the Amazon River in northern Brazil. A port call of several days separated the two legs. CTD temperature, salinity, and oxygen were not reported and so could not be used in evaluating the bottle oxygen data. Neither bottle numbers nor sample numbers were included in the data set. NO3 (nitrate) was reported, but not a separate NO2 (nitrite) determination. This suggests that the "nitrate" values in the data set are actually "nitrate plus nitrite" (N+N). For most of the water column, the difference between NO3 and N+N would be negligible, but near the bottom of the mixed layer, NO2 concentrations significantly different from zero could be expected. This point should be checked by the WHPO. The A17 section has a few noisy oxygen samples, which could have been caused by an inexperienced sampler(s). Overall, the nutrient and oxygen data are quite good, with few problems. Comparisons with other WOCE cruises: Detailed examinations of inter-cruise discrepancies have been separately funded. Some preliminary, general observations follow. A17/A10: These two sections intersect near the Rio Grande Rise, which separates the Brazil and Argentine basins at ca. 39°W, 30°S. There is some overlap of salinity in the broad salinity maximum between 2000 and ca. 3300 m, with greater variability in the deeper water. A10 nitrate and phosphate concentrations are mostly higher 1.4 µM and 0.07 µM, respectively, than for A17 in this depth interval. The oxygen and silicate concentrations overlap in the salinity maximum within WOCE specifications. In the bottom waters, the nutrient concentrations at the more southerly A17 stations all increase and become higher than the A10 concentrations. This is probably a real and due to the influence of the Argentine Basin waters, but the offset at mid-depths remains. A17/A08: These sections intersect at ca. 30.5°W, 11.5°S in the west- central Brazil Basin. Although the T/S plots of stations at the crossing are in good agreement [w/in WOCE specifications], there are large differences in the nutrient and oxygen concentrations between the two sections. A17 is higher in oxygen, silicate, and nitrate by 6 - 8 % over most of the water column. (Phosphate was not analyzed on the A08 cruise.) There is some overlap of the silicate data from the two cruises in the mid-depth range, but a clear difference between them in the deep waters. These observations may call into question the quality of the A08 or A17 data. A17/A06: These sections intersect at ca. 43°W, 7.5°N. Nitrate and phosphate concentrations for A17 exceeded A06 by 3- 6% while the A17 oxygen concentrations were 2 - 5 % lower than the A08 oxygen data. There is more overlap of the silicate data from the two cruises Comments on specific stations: A list of stations at which specific bottle data seems to be questionable follows. The Q2 data quality flags for these data have been set to "3." There are a number of Q1 data flags of "5" in the A17.HYD file. These indicate "not reported" data and the values of these oxygen and nutrient data have been reported as "-9" by the data originator. [WOCE specifications called for reporting of bad data, not eliminating it, unless the originator explicitly knew the cause of the problems. We assume that this is the case here but perhaps this should be checked by the WHPO.] "NOP" indicates that we could find "No Obvious Problem". Station Pressure O2 Silicate NO3 PO4 Comments 13 3300.5 NOP High High High All nutrients appear to be too high. 14 3299.3 High Low Low Low Nutrients appear to be low. 31 699.1 Low NOP NOP NOP Single bottle oxygen minimum. 38 300.7 High High High High Possible double-trip with bottle below. 52 3999 High NOP NOP NOP Oxygen appears to be too high. 72 3197.6 High NOP NOP NOP Oxygen appears to be too high. 77 1.8 NOP NOP NOP NOP Theta value is wrong. 80 300.6 High NOP NOP NOP 1 bottle oxygen max. in overall min. 85 500.6 NOP High High High Nutrients look like those from bottle below, possible double-trip? 129 2598.8 High NOP NOP NOP Maybe a sampling problem w/ oxygen. 129 2999 High NOP NOP NOP " " " " 129 4199.1 High NOP NOP NOP " " " " 134 650.3 High Low Low Low Kink in profile. 137 1601.3 High NOP NOP NOP Very high oxygen 142 2200.2 High High High High Odd high silicate. 143 885.8 High High Low Low Possible bottle problem. 143 2200.2 High High Low Low High silicate. This bottle was supposed to be a duplicate, but doesn't agree with its duplicate or the trend of the rest of the profile. 155 401.2 High NOP Low Low Oxygen up in the middle of a minimum; NO3 and PO4 low. 159 3198.4 High NOP NOP NOP Possible sampling problem 160 High NOP NOP NOP Possible sampling problem 167 3548.9 High NOP NOP NOP Possible sampling problem 174 1400.7 High NOP NOP NOP Sampling problems? Nutrients look ok. 174 3398.3 High NOP NOP NOP " " " 174 3697.3 High NOP NOP NOP " " " 174 3997.1 High NOP NOP NOP " " " 175 2699 High NOP NOP NOP Possible sampling problem. 178 1999.9 High NOP NOP NOP Odd 3-bottle oxygen maximum w/ no salt or nutrient feature. 178 2198.2 High NOP NOP NOP See above 178 2398.9 High NOP NOP NOP See above 181 1401.4 High NOP NOP NOP Possible sampling problem. 182 2598.5 High NOP NOP NOP Possible sampling problem. 182 3678.5 High NOP NOP NOP Possible sampling problem. 183 301.8 High NOP NOP NOP High oxygen in the midst of a minimum. 185 200.1 High Low Low Low Bottle problem? 189 2199.7 High NOP NOP NOP Possible sampling problem. 196 3997.3 High NOP NOP NOP Possible sampling problem. 211 3003.4 NOP NOP 0/-9 NOP NO3 not reported. Should be "-9" and not zero. 228 3000.5 Low High High High 1 bottle silicate max. Leaking bottle?