Acquisition/Processing Journal¶

This document contains the status and comments about the acquisition and processing of each cast

Meaning of problems:

P = removed pressure spikes (we can ignore these problems according to A. Thurnerr)
S = increased error because of shear-inverse difference

Log¶

991.01: day 80, 35S/21E, 52 m deep, 39 m off the bottom: processed but stopped at step 5.6 (do_tstim). Cause of error:

??? Attempted to access ts_up(2,1); index out of bounds because size(ts_up)=[1,13].

Error in ==> ld_merge at 63
dt_tmp = ts_up(1,1) - ts_up(2,1);

Error in ==> do_tstim at 63
   ld_merge

possibly because the cast was too shallow?

992.01: day 81, 34S/24E, 53 m deep, 68 m off the bottom: not processed
993.01: day 82, 33S/28E, 1980 m deep, ? m off the bottom: not processed

scanbb gives us zmin: -1433 m, zmax: 1723 and zend: 1723

This is a problem which happened to Jules on I8S 2007. It means that the LADCP, while mounted downward-looking, thinks he is looking upward. To confirm talk to the instrument as follow:

>PS0

>Break                    (might not be a good command)

>CR1

>CK

>PS0

One of the output of PS0 should tell you if the instrument is looking upward or downward (see ORIENTATION). In our case, the ORIENTATION is up and we had to remove the LADCP from the Rosette. We tried to rotate the instrument vertically by 180 deg. without success of putting the orientation back to normal (use the PS0 command to know the orientation). We even tried to unconnect the instrument and wait for about 10 min, the time for the condensators inside the LADCP to discharge, before plugging it again and test the orientatiton. To no avail. We then have to open it. Open the instrument is a delicate operation that only specialized engineers should endeavor. In the big manual, section 4-13.1 describes how to fix the sensor and to definitively put the instrument on an always-downward or always-upward-looking position internally. We did not, however, finalize the procedure and only shake up the mercury-containing component, the so-called MT1. We then tested the orientation and it was now DOWN. We closed the LADCP (the longest and hardiest part of the surgery) and new O-rings were used during this operation. Order new O-rings one size smaller though. We kept checking that the orientation was good. After each try, we let the instrument unplugged to settle down for the 10 minutes necessary to avoid any change. We put the LADCP back to the Rosette and then proceed to the next cast which was the first real cast.

001.01: day 83, 31S/30E, 244 m deep, 26 m off the bottom: UH processed

This is the first real cast and this time the LADCP seems to be ok. We hope it will stay like that during the whole cruise. Insh’Allah. Because the cast was shallow, however, the UH software does not give me any profile for U and V. I will need to try with the LDEO software. Furthermore, because the ctd time series and ctd 2db are not yet available, those processings will have to be re-done.

UH processed and LDEO processed

Problem with LDEO (from warning): “198 horizontal velocities > 3m/s during the middle of cast”. Probably ok according to A. Turnherr.

002.01: day 83, 31S/30E, 843 m deep, 15 m off the bottom: UH processed and LDEO processed

This time the UH software gave me some profiles.

Problem with LDEO (from warning): “large U bottom track bias”: reprocessed without bottom-tracking and compared to UH solution. UH solution seems to be in-between the two LDEO solutions. Waiting for an answer from Andreas to know which solution is the best.

003.02: day 83, 31S/30E, 1206 m deep, 18 m off the bottom: UH processed and LDEO processed
004.01: day 83, 31 6.39S/30 25.51E: UH processed and LDEO processed

Problem with LDEO (from warning): S. Nothing can be done.

005.02: day 83, 31 8.75S/30 32.2E: UH processed and LDEO processed

Problem with LDEO (from warning): S. Nothing can be done.

006.01: day 83, 31 11.25S/30 37.5E, 2817 m deep, 18 m off the bottom: UH processed and LDEO processed

Problem with LDEO (from warning): S. Nothing can be done.

007.01: day 84, 31 19.9S/30 46.6E, 2974 m deep, 17 m off the bottom: UH processed and LDEO processed
008.01: day 84, 31 29.7S/30 58.4E, 2939 m deep, 10 m off the bottom: UH processed and LDEO processed
009.02: day 84, 31 38.2S/31 11.15E, 3164 m deep, 11 m off the bottom: UH processed and LDEO processed
010.01: day 84, 31 47.5S/31 23.5E, 3347 m deep, 15 m off the bottom: UH processed and LDEO processed
011.01: day 85, 31 56.5S/31 36E, 3568 m deep, 16.3 m off the bottom: UH processed and LDEO processed
012.01: day 85, 32 03S/31 57 E: UH processed and LDEO processed
013.02: day 85, 32 10.8S/32 19.2E, 3598 m deep, 9.0 m off the bottom: UH processed and LDEO processed
014.01: day 85, 32 18.0S/32 40.7E, 3539 m deep, 11.0 m off the bottom: UH processed and LDEO processed
015.01: day 86, 32 25.5S/33 2.4E, 3577 m deep, 12.5 m off the bottom: UH processed and LDEO processed

Problem of bottom track with LDEO software. This station might not be the only one with that problem. NEED TO REVIEW ALL PROFILES PROCESSED WITH LDEO SOFTWARE.

016.01: day 86, 32 32.7S/33 24.0E, 3555 m deep, 14.0 m off the bottom: UH processed and LDEO processed
017.01: day 86, 32 37.0S/33 45.0E, 3059 m deep, 9.6 m off the bottom: UH processed and LDEO processed
018.01: day 86, 32 41.0S/34 7.3E, 2512 m deep, 8.0 m off the bottom: UH processed and LDEO processed
019.02: day 86, 32 46.4S/34 29.1E, 1522 m deep, 13.8 m off the bottom: UH processed and LDEO processed
020.01: day 87, 32 53.5S/35 2.1E, 1587 m deep, 13.9 m off the bottom: UH processed and LDEO processed
021.01: day 87, 32 59.5S/35 35.0E, 1460 m deep, 13.0 m off the bottom: UH processed and LDEO processed
022.01: day 87, 32 59.0S/36 9.0E, 2193 m deep, 12.0 m off the bottom: UH processed and LDEO processed
023.02: day 87, 32 59.0S/36 26.0E, 2934 m deep, 11.0 m off the bottom: UH processed and LDEO processed
024.01: day 87, 32 59.9S/36 28.7E, 3743 m deep, 27.6 m off the bottom: UH processed and LDEO processed
025.01: day 88, 32 59.9S/36 29.7E, 4568 m deep, 20.0 m off the bottom: UH processed and LDEO processed
026.01: day 88, 32 59.9S/36 56.0E, 5102 m deep, 9.7 m off the bottom: UH processed and LDEO processed
027.01: day 88, 32 59.9S/37 31.0E, 5134 m deep, 11.0 m off the bottom: UH processed and LDEO processed
028.01: day 88, 32 59.9S/38 6.3E, 5165 m deep, 12.0 m off the bottom: UH processed and LDEO processed
029.01: day 89, 32 59.9S/38 40.8E, 5137 m deep, 11.0 m off the bottom: UH processed and LDEO processed
030.01: day 89, 32 59.9S/39 15.0E, 5193 m deep, 9.0 m off the bottom: UH processed and LDEO processed
031.01: day 89, 32 59.9S/39 50.0E, 5185 m deep, 11.0 m off the bottom: UH processed and LDEO processed
032.01: day 90, 32 59.9S/40 24.0E, 5074 m deep, 11.0 m off the bottom: UH processed and LDEO processed
033.01: day 90, 32 59.9S/40 59.0E, 5044 m deep, 16.0 m off the bottom: UH processed and LDEO processed
034.02: day 90, 32 59.9S/41 33.8E, 4930 m deep, 11.0 m off the bottom: UH processed and LDEO processed
035.01: day 91, 32 59.9S/42 8.5E, 4310 m deep, 10.0 m off the bottom: UH processed and LDEO processed
036.01: day 91, 32 59.9S/42 42.0E, 4453 m deep, 11.0 m off the bottom: UH processed and LDEO processed
037.01: day 91, 32 59.9S/42 49.0E, 3565 m deep, 10.0 m off the bottom: UH processed and LDEO processed
038.01: day 91, 32 59.9S/42 52.0E, 2982 m deep, 12.0 m off the bottom: UH processed and LDEO processed
039.01: day 92, 32 59.9S/43 71.0E, 2140 m deep, ? m off the bottom: UH processed and LDEO processed

Problem with LDEO (from warning): P. Ignored.

040.01: day 92, 32 59.9S/43 21.6E, 1408 m deep, ? m off the bottom: UH processed and LDEO processed
041.01: day 92, 32 59.9S/43 54.5E, 902 m deep, 13.3 m off the bottom: UH processed and LDEO processed

Problem with LDEO (from warning): P. Ignored.

042.01: day 92, 32 59.9S/44 28.0E, 956 m deep, 12.0 m off the bottom: UH processed and LDEO processed
043.02: day 92, 33 4.3S/45 4.2E, 1138 m deep, 11.0 m off the bottom: UH processed and LDEO processed
044.01: day 92, 33 9.2S/45 39.6E, 1757 m deep, 11.0 m off the bottom: UH processed and LDEO processed

problem with winch; the rosette sat for about an hour at the end of the cast.

045.01: day 93, 33 13.5S/46 14.0E, 2419 m deep, ? m off the bottom: UH processed and LDEO processed
046.01: day 93, 33 18.0S/46 54.0E, 3037 m deep, 9.0 m off the bottom: UH processed and LDEO processed
047.01: day 93, 33 22.0S/47 25.0E, 3622 m deep, 10.0 m off the bottom: UH processed and LDEO processed
048.01: day 93, 33 27.5S/48 1.4E, 3913 m deep, 10.0 m off the bottom: UH processed and LDEO processed

Problem with LDEO (from warning): P. Ignored.

049.01: day 94, 33 32.0S/48 36.6E, 4137 m deep, 13.0 m off the bottom: UH processed and LDEO processed
050.01: day 94, 33 36.6S/49 11.9E, 4244 m deep, 9.0 m off the bottom: UH processed and LDEO processed
051.02: day 94, 33 41.3S/49 47.5E, 4116 m deep, 9.0 m off the bottom: UH processed and LDEO processed
052.01: day 94, 33 46.0S/50 23.2E, 4433 m deep, 10.0 m off the bottom: UH processed and LDEO processed
053.02: day 95, 33 50.2S/50 58.6E, 4532 m deep, 10.0 m off the bottom: UH processed and LDEO processed
054.01: day 95, 33 55.2S/51 34.2E, 4253 m deep, 11.0 m off the bottom: UH processed and LDEO processed
055.02: day 95, 33 59.9S/52 9.9E, 4490 m deep, 8.0 m off the bottom: UH processed and LDEO processed
056.01: day 96, 33 59.9S/52 48.0E, 5581 m deep, 24.0 m off the bottom: UH processed and LDEO processed

Problem with LDEO (from warning): P. Ignored.

057.02: day 96, 34 0.0S/53 7.5E, 4821 m deep, 10.0 m off the bottom: UH processed and LDEO processed
058.01: day 96, 33 59.8S/53 38.1E, 4511 m deep, 10.0 m off the bottom: UH processed and LDEO processed
059.01: day 96, 33 59.9S/54 10.8E, 4097 m deep, 20.0 m off the bottom: UH processed and LDEO processed
060.01: day 97, 33 59.9S/54 30.7E, 2023 m deep, 10.5 m off the bottom: UH processed and LDEO processed
061.01: day 97, 33 59.9S/54 52.9E, 3455 m deep, 10.0 m off the bottom: UH processed and LDEO processed
062.02: day 97, 33 59.9S/55 17.6E, 1661 m deep, 13.0 m off the bottom: UH processed and LDEO processed
063.01: day 97, 33 59.9S/55 45.1E, 4437 m deep, 10.0 m off the bottom: UH processed and LDEO processed
064.01: day 97, 33 59.9S/56 5.5E, 2267 m deep, 19.5 m off the bottom: UH processed and LDEO processed
065.01: day 98, 33 59.9S/56 26.8E, 3855 m deep, 12.0 m off the bottom: UH processed and LDEO processed
066.01: day 98, 33 59.9S/56 59.2E, 5148 m deep, 11.0 m off the bottom: UH processed and LDEO processed

Stations 66 to 70 are exploring the southern edge of the Atlantis II Fracture Zone.

067.01: day 98, 33 42.0S/57 2.0E, 5090 m deep, 10.0 m off the bottom: UH processed and LDEO processed
068.01: day 98, 33 12.0S/57 3.0E, 6002 m deep, 273.0 m off the bottom: UH processed and LDEO processed
069.01: day 99, 33 33.5S/57 2.5E, 5459 m deep, 20.0 m off the bottom: UH processed and LDEO processed
070.01: day 99, 33 50.8S/57 3.8E, 4683 m deep, 10.0 m off the bottom: UH processed and LDEO processed
071.02: day 99, 34 0.0S/57 31.2E, 5324 m deep, 9.0 m off the bottom: UH processed and LDEO processed
072.01: day 99, 33 59.9S/57 51.5E, 4482 m deep, 10.0 m off the bottom: UH processed and LDEO processed
073.02: day 100, 33 59.9S/58 10.8E, 5220 m deep, 9.0 m off the bottom: UH processed and LDEO processed
074.01: day 100, 33 59.9S/58 45.2E, 3900 m deep, 10.0 m off the bottom: UH processed and LDEO processed
075.02: day 100, 33 59.9S/59 19.1E, 5666 m deep, 11.0 m off the bottom: UH processed and LDEO processed
076.01: day 101, 33 59.9S/59 58.8E, 5017 m deep, 12.5 m off the bottom: UH processed and LDEO processed
077.01: day 101, 33 59.9S/60 33.1E, 5524 m deep, 15.0 m off the bottom: UH processed and LDEO processed

‘The Deadliest Cast’: cast started at the beginning of a tropical storm that reached upper 50 knots when the rosette was retrieved. The bottles were closed without stopping the winch. Problem with LDEO (from warning): P. Ignored.

078.01: day 102, 33 59.9S/61 7.45E, 5163 m deep, 10.0 m off the bottom: UH processed and LDEO processed

Problem with LDEO (from warning): P. Ignored.

079.01: day 103, 33 59.9S/61 41.7E, 4847 m deep, 9.8 m off the bottom: UH processed and LDEO processed
080.01: day 103, 33 59.9S/62 16.0E, 4983 m deep, 11.0 m off the bottom: UH processed and LDEO processed
081.02: day 103, 33 59.9S/62 50.4E, 4768 m deep, 9.0 m off the bottom: UH processed and LDEO processed
082.01: day 104, 34 00.0S/63 24.5E, 4822 m deep, 11.0 m off the bottom: UH processed and LDEO processed
083.01: day 104, 34 00.0S/63 58.9E, 4626 m deep, 10.0 m off the bottom: UH processed and LDEO processed
084.01: day 104, 34 00.0S/64 33.3E, 5208 m deep, 10.0 m off the bottom: UH processed and LDEO processed
085.02: day 104, 34 00.0S/65 7.5E, 4657 m deep, 8.0 m off the bottom: UH processed and LDEO processed
086.01: day 105, 34 00.0S/65 41.8E, 4508 m deep, 8.0 m off the bottom: UH processed and LDEO processed
087.02: day 105, 34 00.0S/66 15.9E, 4775 m deep, 10.0 m off the bottom: UH processed and LDEO processed

Problem with LDEO (from warning): P. Ignored.

088.01: day 105, 34 00.0S/66 50.3E, 4775 m deep, 11.0 m off the bottom: UH processed and LDEO processed

Problem with LDEO (from warning): P. Ignored.

089.01: day 105, 34 00.0S/67 24.7E, 4699 m deep, 10.0 m off the bottom: UH processed and LDEO processed
090.01: day 106, 34 00.0S/67 58.9E, 4593 m deep, 11.0 m off the bottom: UH processed and LDEO processed
091.02: day 106, 34 00.0S/68 33.3E, 4599 m deep, 10.0 m off the bottom: UH processed and LDEO processed
092.01: day 106, 34 00.0S/69 7.6E, 4561 m deep, 10.0 m off the bottom: UH processed and LDEO processed
093.01: day 107, 34 00.0S/69 41.9E, 4554 m deep, 11.0 m off the bottom: UH processed and LDEO processed
094.01: day 107, 34 00.0S/70 16.2E, 4053 m deep, 11.0 m off the bottom: UH processed and LDEO processed
096.01: day 107, 34 00.0S/71 24.7E, 4490 m deep, 11.0 m off the bottom: UH processed and LDEO processed
097.01: day 108, 34 00.0S/71 59.2E, 4833 m deep, 11.0 m off the bottom: UH processed and LDEO processed
098.01: day 108, 34 00.0S/72 33.4E, 4208 m deep, 11.0 m off the bottom: UH processed and LDEO processed
099.02: day 108, 34 1.0S/73 7.6E, 4185 m deep, 11.0 m off the bottom: UH processed and LDEO processed
100.01: day 108, 34 47.9S/72 48.0E, 4811 m deep, 11.5 m off the bottom: UH processed and LDEO processed

The next 15 stations follow a NE course across the Southeastern Indian Ocean Ridge

101.01: day 109, 34 24.2S/73 14.9E, 4987 m deep, 10.0 m off the bottom: UH processed and LDEO processed
102.02: day 109, 34 0.4S/73 41.9E, 4974 m deep, 10.0 m off the bottom: UH processed and LDEO processed

Problem with ctd data during the upper 1500 m of the downcast. UH processing is ok but LDEO needs to be processed without ctd data. The 2-dbar ctd data that are published are usually from the downcast. For this station, because of missing data, the upcast data has been published. The 2-dbar data has been reversed in time, however, so that it looks like it is a downcast. The differences with 2-dbar downcast data are: 1) the elapse time starts from zero although it starts usually with the amount of seconds since the start of the ctd cast and the arrival of the rosette in the water, 2) the time step for the pressure to change by 2 dbars changes because of the closing of bottles, while during the downcast the rosette goes down at a constant speed and the time step is about the same. The ctd time series is also different: it misses the first part until 1200 m deep.

103.01: day 109, 33 36.7S/74 9.0E, 4897 m deep, 10.0 m off the bottom: UH processed and LDEO processed
104.01: day 110, 33 12.7S/74 36.0E, 4893 m deep, 12.0 m off the bottom: UH processed and LDEO processed
105.01: day 110, 32 3.0S/75 3.0E, 3932 m deep, 11.0 m off the bottom: UH processed and LDEO processed
106.02: day 110, 32 25.2S/75 30.1E, 3604 m deep, 9.0 m off the bottom: UH processed and LDEO processed
107.01: day 110, 32 0.0S/76 0.2E, 3444 m deep, 10.5 m off the bottom: UH processed and LDEO processed
108.01: day 111, 31 46.0S/76 28.1E, 3095 m deep, 11.0 m off the bottom: UH processed and LDEO processed
109.01: day 111, 31 32.1S/76 56.0E, 2645 m deep, 9.0 m off the bottom: UH processed and LDEO processed
110.02: day 111, 31 18.2S/77 24.0E, 3160 m deep, 10.0 m off the bottom: UH processed and LDEO processed
111.01: day 111, 31 4.3S/77 51.8E, 3307 m deep, 12.0 m off the bottom: UH processed and LDEO processed
112.01: day 112, 30 50.4S/78 19.7E, 3281 m deep, 11.4 m off the bottom: UH processed and LDEO processed
113.01: day 112, 30 36.6S/78 47.4E, 3517 m deep, 11.0 m off the bottom: UH processed and LDEO processed
114.02: day 112, 30 22.8S/79 15.1E, 3893 m deep, 11.0 m off the bottom: UH processed and LDEO processed
115.01: day 112, 30 31.0S/79 33.1E, 3642 m deep, 13.7 m off the bottom: UH processed and LDEO processed
116.01: day 113, 30 55.2S/79 51.1E, 3727 m deep, 10.0 m off the bottom: UH processed and LDEO processed
117.01: day 113, 31 11.2S/80 9.1E, 3865 m deep, 10.0 m off the bottom: UH processed and LDEO processed
118.02: day 113, 31 11.3S/80 45.2E, 4094 m deep, 9.0 m off the bottom: UH processed and LDEO processed
119.01: day 113, 31 11.2S/81 21.4E, 4381 m deep, 10.0 m off the bottom: UH processed and LDEO processed
120.01: day 114, 31 11.2S/81 57.6E, 4035 m deep, 11.0 m off the bottom: UH processed and LDEO processed
121.01: day 114, 31 11.2S/82 33.8E, 3714 m deep, 9.0 m off the bottom: UH processed and LDEO processed
122.02: day 114, 31 11.2S/83 9.9E, 4062 m deep, 11.0 m off the bottom: UH processed and LDEO processed
123.01: day 114, 31 11.2S/83 46.0E, 3784 m deep, 11.0 m off the bottom: UH processed and LDEO processed
124.01: day 115, 31 11.2S/84 22.0E, 4097 m deep, 10.6 m off the bottom: UH processed and LDEO processed
125.01: day 115, 31 11.2S/84 58.4E, 4457 m deep, 11.0 m off the bottom: UH processed and LDEO processed
126.02: day 115, 31 17.5S/85 32.3E, 3948 m deep, 9.0 m off the bottom: UH processed and LDEO processed
127.01: day 115, 31 23.0S/85 5.4E, 3115 m deep, 9.3 m off the bottom: UH processed and LDEO processed
128.01: day 116, 31 21.5S/86 31.8E, 3614 m deep, 10.0 m off the bottom: UH processed and LDEO processed
129.01: day 116, 31 30.8S/86 51.8E, 2946 m deep, 10.0 m off the bottom: UH processed and LDEO processed
130.01: day 116, 31 34.3S/87 12.3E, 4457 m deep, 9.0 m off the bottom: UH processed and LDEO processed

Stations 130 to 132, the figure showing the number of shear samples in a given depth bin is a little bit odd with a peak largest than others in the middle of the water column. Spikes are usually caused by the rosette stopping for bottle sampling. There will also be lower numbers at two distances from the bottom because of previous ping editing. So it is probably normal.

131.02: day 116, 31 40.0S/87 45.7E, 1413 m deep, 11.0 m off the bottom: UH processed and LDEO processed
132.01: day 116, 31 44.9S/88 15.9E, 2253 m deep, 10.0 m off the bottom: UH processed and LDEO processed
133.01: day 117, 31 9.2S/88 41.7E, 3232 m deep, 11.0 m off the bottom: UH processed and LDEO processed
134.01: day 117, 31 54.5S/89 13.7E, 3500 m deep, 9.0 m off the bottom: UH processed and LDEO processed
135.02: day 117, 31 59.9S/89 45.6E, 3761 m deep, 10.0 m off the bottom: UH processed and LDEO processed
136.01: day 117, 32 5.2S/90 17.5E, 4210 m deep, 10.7 m off the bottom: UH processed and LDEO processed
137.01: day 118, 32 10.6S/90 49.4E, 4065 m deep, 8.0 m off the bottom: UH processed and LDEO processed
138.01: day 118, 32 24.2S/91 20.4E, 4125 m deep, 11.0 m off the bottom: UH processed and LDEO processed
139.02: day 118, 32 37.7S/91 51.5E, 3822 m deep, 10.0 m off the bottom: UH processed and LDEO processed
140.01: day 118, 32 51.4S/92 22.7E, 4665 m deep, 11.2 m off the bottom: UH processed and LDEO processed

Problem with LDEO (from warning): P. Ignored.

141.01: day 119, 33 5.0S/92 53.9E, 4387 m deep, 10.0 m off the bottom: UH processed and LDEO processed
142.01: day 119, 33 18.7S/93 25.2E, 4375 m deep, 10.0 m off the bottom: UH processed and LDEO processed
143.02: day 119, 33 32.3S/93 56.6E, 4452 m deep, 11.0 m off the bottom: UH processed and LDEO processed
144.01: day 119, 33 46.0S/94 28.0E, 4603 m deep, 11.0 m off the bottom: UH processed and LDEO processed
145.02: day 120, 33 60.0S/94 60.0E, 4513 m deep, 9.0 m off the bottom: UH processed and LDEO processed
146.01: day 120, 33 60.0S/95 33.6E, 4485 m deep, 9.0 m off the bottom: UH processed and LDEO processed
147.02: day 120, 33 60.0S/96 7.9E, 4415 m deep, 11.7 m off the bottom: UH processed and LDEO processed
148.01: day 120, 33 60.0S/96 42.3E, 4665 m deep, 11.0 m off the bottom: UH processed and LDEO processed
149.02: day 121, 33 60.0S/97 16.5E, 4505 m deep, 10.0 m off the bottom: UH processed and LDEO processed
150.01: day 121, 33 60.0S/97 51.0E, 4451 m deep, 10.0 m off the bottom: UH processed and LDEO processed
151.01: day 121, 33 60.0S/98 25.1E, 4840 m deep, 11.0 m off the bottom: UH processed and LDEO processed
152.01: day 122, 33 60.0S/98 59.4E, 4797 m deep, 12.0 m off the bottom: UH processed and LDEO processed
153.02: day 122, 33 38.0S/99 21.8E, 4219 m deep, 11.0 m off the bottom: UH processed and LDEO processed
154.01: day 122, 33 15.4S/99 44.2E, 4612 m deep, 10.0 m off the bottom: UH processed and LDEO processed
155.01: day 122, 32 53.1S/100 6.5E, 5759 m deep, 10.0 m off the bottom: UH processed and LDEO processed
156.01: day 123, 32 47.5S/100 12.3E, 4381 m deep, 12.0 m off the bottom: UH processed and LDEO processed
157.01: day 123, 32 45.1S/100 14.6E, 4040 m deep, 10.0 m off the bottom: UH processed and LDEO processed
158.01: day 123, 32 41.6S/100 18.2E, 3115 m deep, 9.0 m off the bottom: UH processed and LDEO processed
159.01: day 123, 32 22.2S/100 37.5E, 2406 m deep, 10.0 m off the bottom: UH processed and LDEO processed
160.01: day 123, 32 0.6S/100 59.4E, 2256 m deep, 10.0 m off the bottom: UH processed and LDEO processed
161.01: day 124, 32 0.6S/101 34.3E, 2149 m deep, 12.0 m off the bottom: UH processed and LDEO processed
162.01: day 124, 32 0.6S/101 52.1E, 3005 m deep, 9.0 m off the bottom: UH processed and LDEO processed
163.02: day 124, 32 0.6S/101 58.0E, 3759 m deep, 10.0 m off the bottom: UH processed and LDEO processed
164.01: day 124, 32 0.6S/102 5.0E, 4452 m deep, 10.0 m off the bottom: UH processed and LDEO processed
165.01: day 124, 32 0.6S/102 25.8E, 5217 m deep, 12.0 m off the bottom: UH processed and LDEO processed
166.01: day 125, 31 60.0S/102 59.4E, 5344 m deep, 9.0 m off the bottom: UH processed and LDEO processed
167.01: day 125, 31 48.2S/103 27.0E, 5349 m deep, 9.0 m off the bottom: UH processed and LDEO processed
168.01: day 125, 31 36.3S/103 54.5E, 5286 m deep, 10.0 m off the bottom: UH processed and LDEO processed
169.01: day 126, 31 24.5S/104 22.0E, 4902 m deep, 11.0 m off the bottom: UH processed and LDEO processed
170.02: day 126, 31 12.8S/104 49.3E, 5838 m deep, 9.0 m off the bottom: UH processed and LDEO processed
171.01: day 126, 31 9.4S/104 57.1E, 4218 m deep, 10.0 m off the bottom: UH processed and LDEO processed
172.01: day 126, 31 3.3S/105 11.5E, 2982 m deep, 12.0 m off the bottom: UH processed and LDEO processed
173.01: day 126, 31 4.0S/105 17.6E, 4430 m deep, 10.0 m off the bottom: UH processed and LDEO processed
174.01: day 127, 31 5.2S/105 27.5E, 5271 m deep, 10.0 m off the bottom: UH processed and LDEO processed
175.02: day 127, 31 9.4S/106 2.7E, 5239 m deep, 10.0 m off the bottom: UH processed and LDEO processed
176.01: day 127, 31 13.4S/106 38.0E, 5161 m deep, 11.4 m off the bottom: UH processed and LDEO processed
177.01: day 127, 31 17.6S/107 13.3E, 5147 m deep, 12.0 m off the bottom: UH processed and LDEO processed
178.01: day 128, 31 21.6S/107 48.6E, 5402 m deep, 9.0 m off the bottom: UH processed and LDEO processed
179.02: day 128, 31 25.7S/108 24.0E, 5426 m deep, 10.0 m off the bottom: UH processed and LDEO processed
180.01: day 128, 31 29.9S/108 59.3E, 5285 m deep, 10.0 m off the bottom: UH processed and LDEO processed
181.02: day 129, 31 35.7S/109 33.1E, 5327 m deep, 14.0 m off the bottom: UH processed and LDEO processed
182.01: day 129, 31 42.3S/110 6.1E, 5208 m deep, 10.0 m off the bottom: UH processed and LDEO processed
183.02: day 129, 31 49.0S/110 39.1E, 5169 m deep, 10.0 m off the bottom: UH processed and LDEO processed
184.01: day 129, 31 55.7S/111 12.3E, 5130 m deep, 10.0 m off the bottom: UH processed and LDEO processed
185.02: day 130, 32 2.4S/111 45.6E, 5094 m deep, 9.0 m off the bottom: UH processed and LDEO processed
186.01: day 130, 32 9.1S/112 18.7E, 5064 m deep, 10.0 m off the bottom: UH processed and LDEO processed
187.01: day 130, 32 15.8S/112 52.0E, 4847 m deep, 11.0 m off the bottom: UH processed and LDEO processed
188.01: day 131, 32 22.5S/113 25.3E, 4650 m deep, 9.0 m off the bottom: UH processed and LDEO processed
189.02: day 131, 32 29.3S/113 58.5E, 4090 m deep, 10.0 m off the bottom: UH processed and LDEO processed
190.01: day 131, 32 31.0S/114 7.1E, 3232 m deep, 10.0 m off the bottom: UH processed and LDEO processed
191.01: day 131, 32 31.9S/114 11.1E, 2601 m deep, 10.0 m off the bottom: UH processed and LDEO processed
192.01: day 131, 32 31.9S/114 22.4E, 1852 m deep, 15.0 m off the bottom: UH processed and LDEO processed
193.01: day 132, 32 35.2S/114 28.0E, 984 m deep, 7.0 m off the bottom: UH processed and LDEO processed
194.01: day 132, 32 37.9S/114 40.8E, 622 m deep, 8.0 m off the bottom: UH processed and LDEO processed
195.01: day 132, 32 39.8S/114 50.8E, 203 m deep, 8.0 m off the bottom: UH processed and LDEO processed

Summary of problems with LDEO processing:

Specific problems: 1 (ignored), 2 (being treated)
S problems: 4 thru 6 (nothing can be done)
P problems: 39, 41, 48, 56, 77, 78, 87, 88. These problems can be ignored.

Notes on the warning “shear-inverse difference”¶

Here are some notes concerning ways to correct the problem generating the warning “shear-inverse difference”. When I first got this warning, A. Thurnherr offered this first advice:

“1) The warning ” increased error because of shear - inverse difference” is very important as it points to a significant inconsistency between the inverse and a shear solution. All stations with this warning should be investigated in detail. Quite often, this warning has to do with insufficient range, but this is not the case for your data.

You should check to see whether the beginning and end positions calculated by the LDEO software (these are reported in the log files) are consistent with what the UH software uses. I say this because the vertically averaged u velocities calculated by the two processing methods are significantly different for both profiles. Some users furthermore report occasional problems with the LDEO software getting these values right.

Most importantly, you should re-process the data with the LDEO software without the BT [bottom-tracking] constraint. This will indicate whether the bogus shear (especially in the u component from station 20) is caused by bad editing of the LADCP ping data or by inconsistent velocity-referencing constraints. The way BT data are estimated for the BB150 instrument has never been tested and there are reasons to be suspicious of BT velocities collected during casts with significant ship drift. Note that the problem in both casts is in the component associated with significant drift.”

Then, I realized that there was indeed difference between the start/end positions of the cast read by the LDEO software and those given by the CTD group and read by the UH software. A. Thurnherr then gave me this follow-up:

“Ok, so the problem are incorrect start positions. I have heard about this problem but I have not yet encountered it myself.

Solve the immediate problem of the bad casts. You can do this by manually setting the start/end position. If you have my HowTo document you’ll find some pointers there in section 3. Essentially, what you need to do is set p.poss and p.pose in an if-statement in set_cast_params.m; for details on the format of poss and pose see defaults.m.”

Because in the manual, it is written that “Once GPS time-series data are included in processing it is important that the magnetic declination (p.drot, or p.poss and p.pose) are not set manually” [See p. 4, 5 and 11 in LDEO How-To [PDF] ], I was a bit confused of what to do exactly with p.poss and p.pose:

“Andreas, if I impose p.poss and p.pose, what is going on then with the magnetic declination; I am not sure I understand if these are related or not.”

Here was A. Thurnherr’s answer:

“That’s one of these things: yes, they are related but i am not entirely sure what happens if you set poss and pose. The software is very convoluted. Perhaps you’ll have to not load the GPS data for those casts (by setting f.nav = ' '; — note that there is a space between the ‘’; it might work without the space but I am sure that it will work with it). Perhaps you’ll have to set the magnetic declination manually, but I don’t think so. The way to deal with this is to try to set poss and pose without changing anything else and see whether it works as intended. If it does not, then set f.nav = ' '; If that does not give you the correct magnetic deviation, set that manually, too.”

Then, A. Thurnherr worked on the bug and provided me with a new version of the LDEO software, IX_6beta. Here was the text that was attached with the new software:

“A few months ago I fixed a bug related to the start/end position. It occurs primarily when the LADCP collects data for quite a while before the CTD is turned on. I think that’s what happened on your station 15. The bug is fixed in version 6beta, which you should find attached to this email. I have not checked carefully but at a quick glance the solutions calculated with this version seem to agree much better with the UH solution (2nd attachment). BTW, if you want the most up-to-date version, you should rename loadrdi.debugged to loadrdi.m. There’s a very simple-minded experimental wake-editing code in there that can try out if you want (I don’t expect much, though) by setting p.ignore_wake_beam = 1; Let me know if you do and what you find.”

Later on, A. Thurnherr found a mistake in my set_cast_params.m which resulted in the LDEO solution matching the UH one.

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