WHOTS Mooring Subsurface Instrumentation

UH Contributions to WHOTS-13 Cruise Report by Fernando Santiago-Mandujano, Daniel McCoy, Jefrey Snyder, R. Walter Deppe, Kellen Rosburg, Glenn Carter, Katrina Berry, and Roger Lukas WHOTS Mooring Subsurface Instrumentation 1. WHOTS-13 Deployment For the 13th WHOTS mooring deployment that took place on 26 June 2016, UH provided 16 SBE-37 MicroCATs and two RDI Workhorse ADCPs (300 and 600 khz). In addition to the instrumentation on the buoy, WHOI provided two Vector Measuring Current Meters (VMCM), two deep MircoCATs (SBE-37), and all required subsurface mooring hardware. The MicroCATs all measure temperature and conductivity, with 7 also measuring pressure. All MicroCATs were deployed with antifoulant capsules. Information about these instruments, including location on the mooring, is given in Table 1. Before deployment, a bag of ice was placed in contact with each MicroCAT s temperature sensor, except for the WHOI MicroCATs, to produce a spike in the data as a reference point to check the instrument clocks. WHOI MicroCATs were spiked by submerging them in a cold water bath. 1

Table 1. WHOTS-13 mooring subsurface instrument deployment information. All times are in UTC (MM/DD/YY hh:mm:ss) SN Instrument Depth (m) Pressure SN Sample Interval (sec) Start Logging Data Cold Spike Begin Cold Spike End Time in Water 6892 MicroCAT 7 51324 75 6/23/16 0:00:00 6/24/16 22:16:00 6/24/16 22:46:00 6/26/16 18:33:00 2016 VMCM 10 N/A 60 6/19/16 20:58:00 N/A N/A N/A N/A 6/26/16 18:33:00 3382 MicroCAT 15 N/A 180 6/23/16 0:00:00 6/24/16 22:16:00 6/24/16 22:46:00 6/26/16 18:29:00 4663 MicroCAT 25 N/A 180 6/23/16 0:00:00 6/24/16 22:16:00 6/24/16 22:46:00 6/26/16 18:20:00 2075 VMCM 30 N/A 60 6/19/16 22:05:00 N/A N/A N/A N/A 6/26/16 18:19:00 3633 MicroCAT 35 N/A 180 6/23/16 0:00:00 6/24/16 22:16:00 6/24/16 22:46:00 6/26/16 18:15:00 3381 MicroCAT 40 N/A 180 6/23/16 0:00:00 6/24/16 22:16:00 6/24/16 22:46:00 6/26/16 18:10:00 3668 MicroCAT 45 5579 240 6/23/16 0:00:00 6/24/16 22:16:00 6/24/16 22:46:00 6/26/16 18:05:00 13917 600 khz ADCP 47.5 N/A 600 6/23/16 0:00:00 N/A See Table 2 N/A See Table 2 6/26/16 19:37:00 3619 MicroCAT 50 N/A 180 6/23/16 0:00:00 6/24/16 22:16:00 6/24/16 22:46:00 6/26/16 19:37:00 3620 MicroCAT 55 N/A 180 6/23/16 0:00:00 6/24/16 22:16:00 6/24/16 22:46:00 6/26/16 19:39:00 3621 MicroCAT 65 N/A 180 6/23/16 0:00:00 6/24/16 22:16:00 6/24/16 22:46:00 6/26/16 19:40:00 3632 MicroCAT 75 N/A 180 6/23/16 0:00:00 6/24/16 22:16:00 6/24/16 22:46:00 6/26/16 19:42:00 4699 MicroCAT 85 10209 240 6/23/16 0:00:00 6/24/16 22:16:00 6/24/16 22:46:00 6/26/16 19:43:00 3791 MicroCAT 95 N/A 180 6/23/16 0:00:00 6/24/16 22:16:00 6/24/16 22:46:00 6/26/16 19:44:00 2769 MicroCAT 105 2949 240 6/23/16 0:00:00 6/24/16 22:16:00 6/24/16 22:46:00 6/26/16 19:45:00 4700 MicroCAT 120 9944 240 6/23/16 0:00:00 6/24/16 22:16:00 6/24/16 22:46:00 6/26/16 19:53:00 7637 300 khz ADCP 125 N/A 600 6/23/16 0:00:00 N/A See Table 2 N/A See Table 2 6/26/16 19:54:00 2965 MicroCAT 135 3021 240 6/23/16 0:00:00 6/24/16 22:16:00 6/24/16 22:46:00 6/26/16 19:55:00 4701 MicroCAT 155 10211 240 6/23/16 0:00:00 6/24/16 22:16:00 6/24/16 22:46:00 6/26/16 19:57:00 12246 MicroCAT 36m off bottom N/A 300 6/15/16 1:00:00 6/23/16 20:11:00 6/23/16 21:46:00 6/27/16 8:13:00 12247 MicroCAT 36m off bottom N/A 300 6/15/16 1:00:00 6/23/16 20:11:00 6/23/16 21:46:00 6/27/16 8:13:00 The ADCPs were deployed in an upward-looking configuration. The instruments were programmed as described in Table 2. Before deployment, each instrument s transducer was rubbed gently by hand for 10 seconds to produce a spike in the data as a reference point to check the instrument s clock. Table 2. WHOTS-13 mooring ADCP deployment and configuration information. All times are in UTC. ADCP S/N 7637 ADCP S/N 13917 Frequency (khz) 300 600 Number of Depth Cells 30 25 Depth Cell Size (m) 40 80 Pings per Ensemble 4 m 2 m Time per Ensemble (min) 10 min 10 min Time per Ping (sec) 4 sec 2 sec Time of First Ping 06/25/16, 00:10:05 06/25/16, 00:49:54 Transducer 1 Spike Time 06/25/16, 01:00:10 06/25/16, 00:50:30 Transducer 2 Spike Time 06/25/16, 01:00:20 06/25/16, 00:50:40 2

Transducer 3 Spike Time 06/25/16, 01:00:30 06/25/16, 00:50:50 Transducer 4 Spike Time 06/25/16, 01:00:40 06/25/16, 00:51:00 Time in Water 06/26/17, 19:54:00 06/25/16, 00:51:00 Depth (m) 125 m 47.5 m 2. WHOTS-12 Mooring For the 12th WHOTS mooring deployment that took place on 11 July 2015, UH provided 17 SBE-37 MicroCATs, and one RDI Workhorse ADCP (300 khz). Sea-Bird (David Murphy) provided three experimental SBE-37 MicroCATs. In addition to the instrumentation on the buoy, WHOI provided two Vector Measuring Current Meters (VMCM), one MicroCAT (SBE-37), one RDI Workhorse ADCP (600 khz), and all required subsurface mooring hardware. The MicroCATs all measure temperature and conductivity, with 6 also measuring pressure. All MicroCATs were deployed with antifoulant capsules. Tables 3a and Table 3b provide the deployment information for these instruments on the WHOTS-12 mooring. Before deployment, a bag of ice was placed in contact with each MicroCAT s temperature sensor, except for the WHOI MicroCAT, to produce a spike in the data as a reference point to check the instrument s clock. The WHOI MicroCAT was spiked by submerging it in a cold water bath. To produce a spike in the ADCP data each instrument s transducer was rubbed gently by hand for 20 seconds. Table 3a. WHOTS-12 mooring subsurface instrument deployment information. All times are in UTC (MM/DD/YY hh:mm:ss). SN: Instrument Depth (m) Pressure SN Sample Interval (sec) Start Logging Data Cold Spike Begin Cold Spike End Time in Water 3617 MicroCAT 7 N/A 180 07/08/15 0:00:00 07/10/15 02:00:00 7/10/15 02:30:00 07/11/15 19:52:10 19 VMCM 10 N/A 60 07/06/15 19:06:00 N/A N/A N/A N/A 07/11/15 19:32:25 6893 MicroCAT 15 N/A 60 07/08/15 0:00:00 07/10/15 02:00:00 07/10/15 02:30:00 07/11/15 19:28:15 6894 MicroCAT 25 N/A 60 07/08/15 0:00:00 07/10/15 02:00:00 07/10/15 02:30:00 07/11/15 19:22:45 69 VMCM 30 N/A 60 07/06/15 19:06:00 N/A N/A N/A N/A 07/11/15 19:19:16 6895 6896 6887 1825 6897 6898 6899 3618 3634 3670 6889 6890 4891 13584 6888 13585 13586 6891 MicroCAT 35 N/A 60 07/08/15 0:00:00 07/10/15 02:00:00 07/10/15 02:30:00 07/11/15 19:17:53 MicroCAT 40 N/A 60 07/08/15 0:00:00 07/10/15 02:00:00 07/10/15 02:30:00 07/11/15 19:13:17 MicroCAT 45 2651319 75 07/09/15 0:00:00 07/10/15 02:00:00 07/10/15 02:30:00 07/11/15 19:11:24 600 khz ADCP 47.5 N/A 600 07/08/15 0:00:00 N/A See Table 3b N/A See Table 3b 07/11/15 20:05:22 MicroCAT 50 N/A 60 07/08/15 0:00:00 07/10/15 02:00:00 07/10/15 02:30:00 07/11/15 20:06:27 MicroCAT 55 N/A 60 07/08/15 0:00:00 07/10/15 02:00:00 07/10/15 02:30:00 07/11/15 20:08:01 MicroCAT 65 N/A 60 07/08/15 0:00:00 07/10/15 02:00:00 07/10/15 02:30:00 07/11/15 20:08:47 MicroCAT 75 N/A 180 07/08/15 0:00:00 07/10/15 02:00:00 07/10/15 02:30:00 07/11/15 20:09:46 MicroCAT 85 N/A 180 07/08/15 0:00:00 07/10/15 02:00:00 07/10/15 02:30:00 07/11/15 20:11:08 MicroCAT 95 5701 240 07/08/15 0:00:00 07/10/15 02:00:00 07/10/15 02:30:00 07/11/15 20:12:05 MicroCAT 105 2651321 75 07/08/15 0:00:00 07/10/15 02:00:00 07/10/15 02:30:00 07/11/15 20:12:57 MicroCAT 120 2651322 75 07/08/15 0:00:00 07/10/15 02:00:00 07/10/15 02:30:00 07/11/15 20:22:56 300 khz ADCP 9988 MicroCAT 125 N/A 600 07/08/15 0:00:00 N/A See Table 3b N/A See Table 3b 07/11/15 20:23:06 XMC 134 N/A 75 07/10/15 0:00:00 07/10/15 02:00:00 07/10/15 02:30:00 07/11/15 20:27:31 MicroCAT 135 3418742 75 07/08/15 0:00:00 07/10/15 02:00:00 07/10/15 02:30:00 07/11/15 20:27:32 XMC 136 N/A 75 07/10/15 0:00:00 07/10/15 02:00:00 07/10/15 02:30:00 07/11/15 20:27:33 XMC 154 N/A 75 07/10/15 0:00:00 07/10/15 02:00:00 07/10/15 02:30:00 07/11/15 20:30:34 MicroCAT 155 2651323 75 07/08/15 0:00:00 07/10/15 02:00:00 07/10/15 02:30:00 07/11/15 20:30:36 36m off bottom N/A 300 07/10/15 0:00:00 07/10/15 02:00:00 07/10/15 02:30:00 07/12/15 01:33:17 3

10602 MicroCAT 36m off bottom 2136788 300 07/09/15 0:00:00 07/11/15 00:00:00 07/11/15 00:30:00 07/12/15 01:33:17 XMC - Experimental MicroCAT Table 3b. WHOTS-12 mooring ADCP deployment and configuration information. All times are in UTC. ADCP S/N 4891 ADCP S/N 1825 Frequency (khz) 300 600 Number of Depth Cells 30 25 Depth Cell Size (m) 40 80 Pings per Ensemble 4 m 2 m Time per Ensemble (min) 10 min 10 min Time per Ping (sec) 4 sec 2 sec Time of First Ping 07/08/15, 00:00:00 07/08/15, 00:00:00 Transducer 1 Spike Time 07/09/15, 20:00:00 07/09/15, 19:50:00 Transducer 2 Spike Time 07/09/15, 20:00:30 07/09/15, 19:50:30 Transducer 3 Spike Time 07/09/15, 20:01:00 07/09/15, 19:51:00 Transducer 4 Spike Time 07/09/15, 20:01:30 07/09/15, 19:51:30 Time in Water 07/11/15, 20:23:06 07/11/15, 20:05:22 Depth (m) 125 m 47.5 m 3. WHOTS-12 Recovery The WHOTS-12 mooring was recovered on 29-30 June 2016 (UTC). All instruments on the mooring were successfully recovered. Most of the instruments had some degree of biofouling, with the heaviest fouling near the surface. Fouling extended down to the ADCP at 125 m, although it was minor at that level. MicroCATs All MicroCATs except SN 6899 (65 m) were in good condition after recovery. MicroCAT 6899 was recovered without its conductivity guard, but the conductivity cell was in apparent good conditions (Fig. 1a), it also lost both antifoulant plugs and a barnacle was attached to the bottom end of its conductivity cell, partially blocking the flow. The 50 m MicroCAT also lost its bottom antifoulant plug (Fig. 1a). The MicroCATs at 7 and 15 m had pieces of fishing line wrapped around their trawl guards, but the instruments seemed to be in good condition (Fig. 1b). After recovery and before stop recording, a bag of ice was placed in contact with each MicroCAT temperature sensor, to produce a spike in the data as a reference point to check the instrument s clock. To produce a spike in the ADCP data, each instrument s transducer was rubbed gently by hand for 20 seconds. The data from all instruments were downloaded on board the ship, and all instruments returned full data records. Table 4 gives the post-deployment information for the C-T and ADCP instruments. 4

Figure 1a. WHOTS-12, MicroCAT SN 6899 at 65 m (left), recovered without its cell guard and antifoulant plugs, and MicroCAT SN 6897 at 50 m (right), recovered without its bottom antifoulant plug. 5

Figure 1b. WHOTS-12, MicroCAT SN 3617 (7 m; left) and SN 6893 (15 m; right), recovered with fishing lines wrapped around their frames. Table 4. WHOTS-12 mooring C-T and ADCP Instruments recovery information. All times are in UTC. Depth (m) Sea-Bird Serial # 7 SBE 37-3617 15 SBE 37-6893 25 SBE 37-6894 35 SBE 37-6895 40 SBE 37-6896 45 SBE 37-6887 47.5 ADCP 1825 Time out of water 05:43:00 05:48:00 05:53:00 06:00:00 06:02:00 06:06:00 03:40:00 Time of Spike 18:25:00 18:25:00 18:25:00 18:25:00 18:25:00 18:25:00 Time of End Spike 18:55:00 18:55:00 18:55:00 18:55:00 18:55:00 18:55:00 N/A See Table 5 Time Logging Stopped 7/01/16 01:41:30 19:56:00 19:36:00 19:23:30 20:32:00 20:35:00 7/01/16 23:48:00 Samples Logged Data Quality File Name 172353 Good W12_3617.asc 516717 Good W12_6893.asc 516696 Good W12_6894.asc 516683 Good W12_6895.asc 516753 Good W12_6869b.asc 412252 Good W12_6887b.asc 51844 Good wh12_600.000 6

50 SBE 37-6897 55 SBE 37-6898 65 SBE 37-6899 75 SBE 37-3618 85 SBE 37-3634 95 SBE 37-3670 105 SBE 37-6889 120 SBE 37-6890 125 ADCP 4891 134 XMC 13584 135 SBE 37-6888 136 XMC 13585 154 XMC 13586 155 SBE 37-6891 36 mab SBE 37-9988 36 mab SBE 37-10602 03:39:00 03:38:00 03:37:00 03:37:00 03:36:00 03:36:00 03:35:00 03:32:00 03:28:00 03:23:00 03: 23:00 03:23:00 03:21:00 03:21:00 6/29/16 19:59:00 6/29/16 19:59:00 18:25:00 18:25:00 18:25:00 18:25:00 18:25:00 18:25:00 18:25:00 18:25:00 18:55:00 18:55:00 18:55:00 18:55:00 18:55:00 18:55:00 18:55:00 18:55:00 N/A See Table 5 18:25:00 18:25:00 18:25:00 18:25:00 18:25:00 18:25:00 18:25:00 18:55:00 18:55:00 18:55:00 18:55:00 18:55:00 18:55:00 18:55:00 7/01/16 20:36:00 19:42:00 7/01/16 20:56:00 7/01/16 01:45:00 7/2/16 04:38:00 7/2/16 04:34:30 20:00:00 7/01/16 20:47:00 7/02/16 00:36:00 7/01/16 20:29:30 19:49:00 7/01/16 20:33:00 7/02/16 17:53:30 19:53:00 19:31:00 20:53:30 518197 Good W12_6897.asc 516703 Good W12_6898.asc 518217 Good W12_6899.asc 172355 Good W12_3618.asc 172892 Good W12_3634.asc 129668 Good W12_3670.asc 413376 Good W12_6889.asc 414566 Good W12_6890.asc 51840 Good Wh12_300.000 412248 C-offset W12_13584.asc 413368 Good W12_6888.asc 412251 Good W12_13585.asc 413275 Good W12_13586.asc 413370 Good W12_6891.asc 102763 Good W12_9988.asc 103067 C-drift W12_10602.asc The data recovered from the MicroCATs appear to be mostly of high quality, although postdeployment calibrations are required. Figures A1-A21 show the nominally calibrated temperature, conductivity and salinity records from each instrument, and pressure for those instruments that were equipped with pressure sensors. Experimental MicroCAT SN 13584 showed a conductivity offset early in the deployment, MicroCAT SN 10602 deployed 36 mab showed a conductivity sensor drift that started in January 2016, and a pressure drift the first 3 months after being deployed; and MicroCAT SN 9988, also at 36 mab showed a conductivity drift early in the deployment. ADCP Table 5 provides the WHOTS-12 ADCP deployment configuration and recovery information. Table 5. WHOTS-12 mooring ADCP recovery information. All times are in UTC. ADCP S/N 4891 ADCP S/N 1825 Frequency (khz) 300 600 Number of Depth Cells 30 25 Depth Cell Size (m) 40 80 Pings per Ensemble 4 m 2 m Time per Ensemble (min) 10 min 10 min 7

Time per Ping (sec) 4 sec 2 sec Time of First Ping 07/08/15, 00:00:00 07/08/15, 00:00:00 Transducer 1 Spike Time 07/01/16, 00:22:30 07/01/16, 00:27:30 Transducer 2 Spike Time 07/01/16, 00:22:50 07/01/16, 00:27:50 Transducer 3 Spike Time 07/01/16, 00:23:10 07/01/16, 00:28:10 Transducer 4 Spike Time 07/01/16, 00:23:30 07/01/16, 00:28:30 Time in Water 07/11/15, 20:23:06 07/11/15, 20:05:22 Time out of Water 03:28:00 03:40:00 Depth (m) 125 m 47.5 m *WHOTS-12 VMCM recovery information is provided in Table ZZZ [See A. Plueddemann for this ] The fouling on the 300 khz ADCP transducer faces (Figure 2) was minimal, most likely due to the depth of deployment (125 m) as well as Destin rash paste (which contains 40% Zinc oxide) used as anti-foulant on the faces. The transducer faces for the 47.5 m ADCP (Figure 3) were also treated with anti-foulant paste, and despite significant algae growth near the faces, the faces themselves did not show the same level of growth, although a barnacle was found attached to the frame above the transducers. Figure 2. WHOTS-12 ADCP (300 khz) deployed at 125 m, after recovery. 8

Figure 3. WHOTS-12 ADCP (600 khz) deployed at 47.5 m, after recovery. 300 khz ADCP The data from the upward-looking 300 khz ADCP at 125 m were good; the instrument was pinging upon recovery. There appears to be no obviously questionable data from this ADCP at this time, apart from near-surface artifacts. Figure 4 shows the variations of the horizontal and vertical components of velocity in depth and time. Figure 5 shows the heading, pitch and roll information from the ADCP. 600 khz ADCP The data from the upward-looking 600 khz ADCP at 47.5 m were good; the instrument was pinging upon recovery. There appears to be no initial questionable data from this ADCP at this time, apart from near-surface artifacts. Figure 6 shows the variations of the horizontal and vertical components of velocity in depth and time. Figure 7 shows the heading, pitch and roll information from the ADCP. 9

Figure 4. Time-series of eastward, northward and upward velocity components versus bin number measured by the ADCP at 125 m depth on the WHOTS-12 mooring. Height in meters above the transducer is approximately 4 times the bin number. Current speeds greater than 1 m/s are not included. Color bar gives current speed in m/s. 10

Figure 5. Heading, pitch and roll variations measured by the ADCP at 125 m depth on the WHOTS-12 mooring. 11

Figure 6. Time-series of eastward, northward and upward velocity components versus bin number measured by the ADCP at 47.5 m depth on the WHOTS-12 mooring. Height in meters above the transducer is approximately 2 times the bin number. Current speeds greater than 1 m/s are not included. Color bar gives current speed in m/s. 12

Figure 7. Heading, pitch and roll variations measured by the ADCP at 47.5 m depth on the WHOTS-12 mooring. 13

4. CTD Stations UH provided CTD and water sampling equipment, including a Sea-Bird 9/11+ CTD sampling pressure, dual temperature, dual conductivity and dual oxygen sensors at 24 Hz. Sea- Bird sensors used routinely as part of the Hawaii Ocean Time-series were employed to tie the WHOTS cruise data into the HOT CTD dataset. The CTD was installed inside a twelve-place General Oceanics rosette with six 5-liter Niskin sampling bottles controlled by a Sea-Bird carousel. Table 6 provides summary information for all CTD casts, and figures B1-B6 show the water column profile information that was obtained. Table 6. CTD stations occupied during the WHOTS-13 cruise. Station/cast Date (MM/DD/YY, UTC) In-water Time (HH:MM,UTC) Location (using NMEA data) Maximum pressure (dbar) 20/1 06/26/16 04:07 21 27.95 N, 158 21.24 W 1510 52 / 1 06/28/16 00:13 22 39.58 N, 157 58.26 W 203 52 / 2 06/28/16 02:25 22 39.48 N, 157 58.86 W 208 52 / 3 06/28/16 05:02 22 39.30 N, 157 59.50 W 209 52 / 4 06/28/16 07:26 22 39.48 N, 157 58.31 W 208 50 / 1 07/02/16 20:07 22 46.39 N, 157 56.38 W 210 50 / 2 07/02/16 00:51 22 46.26 N, 157 56.46 W 211 50 / 3 07/02/16 05:53 22 46.34 N, 157 56.49 W 209 50 / 4 07/02/16 16:06 22 45.89 N, 157 56.41 W 209 50 / 5 07/02/16 19:52 22 46.46 N, 157 56.66 W 2010 Ten CTD casts were conducted during the WHOTS-13 cruise, from June 26 through July 2. CTD profile data were collected at Station 20 (in transit to the WHOTS mooring), Station 50 (near the WHOTS-13 buoy), and Station 52 (near the WHOTS-12 buoy). The cast at Station 20 was 1500 m deep, and three acoustic releases (two for the WHOTS-13 mooring and one backup) were attached to the rosette frame for function testing. Five CTD yo-yo casts were conducted to obtain profiles for comparison with subsurface instruments on the WHOTS-13 mooring after deployment, and four yo-yo casts were conducted for comparison with the WHOTS-12 mooring before recovery. These were started less than 0.5 nm from the buoys with varying drift during each cast. The comparison casts at Station 52 consisted of 5 up-down cycles between 5 and 200 dbar, while the casts at Station 50 were 3 hour long (about 14 cycles each), also between 50 and 200 dbar. The last cycle of the last cast at this Station 52 was to 2000 dbar as requested by the ship engineers to lubricate the CTD wire during the upcast. Water samples were taken from all casts; 4 samples for each of them. These samples will be analyzed for salinity at UH and used to calibrate the CTD conductivity sensors. 14

5. Thermosalinograph Near-surface temperature and salinity data during the WHOTS-13 cruise were acquired from the thermosalinograph (TSG) system installed on the NOAA Ship Hi ialakai. The sensors were sampling water from the continuous seawater system running through the ship, and were comprised of one thermosalinograph model SBE-21 (SN 3155) and a micro-thermosalinograph model SBE-45 (SN 4537642-0121), both with (internal) temperature and conductivity sensors located in the ship s wet lab, about 67 m from the intake; and an SBE-38 (SN 215) external temperature sensor located at the water intake. The SBE-21 recorded data every 5 seconds, and the other two instruments recorded data every second. The Hi ialaki has a water intake depth of 2 m located at the bow of the ship, next to the starboard side bow thruster. The system had a pressure gauge showing a flow pressure of about 20 psi, decreasing to 18 psi when the water intake was open. Both thermosalinograph systems had a debubbler. The SBE-45 exhibited a large number of conductivity and temperature glitches, indicating a possible problem with the system (Figure 8a). The rest of the conductivity data and the calculated salinity for the SBE-21 seem to be of good quality (Figure 8b). The records from the external and internal temperature sensors are also of good quality, although the external sensor also had some glitches early in the cruise, the internal temperature from the SBE-21 appears to be consistently lower than the external temperature, probably due to cooling from the ship s A/C system while the water travels from the intake to the thermosalinograph. The temperature from the SBE-45 decreased drastically between 1 and 3.5 between June 29 and before July 3. This micro-thermosalinograph uses a much smaller volume of water as compared to the SBE-21, and it seems to be affected more significantly by the wet-lab s temperature changes than the SBE-21. The ship s navigation data are also plotted (Figure 9). 15

Figure 8a. Time-series of Ship Hi ialakai thermosalinograph data from the WHOTS-13 deployment cruise. Times are UTC. 16

Figure 8b. Same as in Figure 8a, but with different scales in the y-axis. 17

Figure 9. Time-series of Ship Hi ialakai navigation data during the WHOTS-13 cruise. 18

6. Shipboard ADCP Currents were measured for the duration of the cruise over the depth range of 30-1000 m with a 75 khz RDI Ocean Surveyor (OS75) ADCP working in narrowband mode with a vertical resolution of 16 m, and in broadband mode with vertical resolution of 8 m. The system yielded good data, shown in Figures 10 and 11. Periods of missing data between 300 and 450 m in the broadband ADCP are apparently due to the lack of scatter material in the water. The gaps in the data occurred when the system was shut down temporarily during communications with the acoustic releases used for the moorings. The long gap on June 28 from about 19:40 to 22:00 UTC was during triangulation of the WHOTS-13 anchor after deployment. 19

Figure 10. Contours of zonal (upper) and meridional (lower) speeds from the narrowband ADCP on the NOAA Ship Hi ialakai during the WHOTS-13 cruise. Positive is to the East (North). 20

Figure 11. Same as in Figure 10, but for the broadband ADCP. 21

7. Weather and Currents See Appendix C for the weather and currents observed during the WHOTS-13 cruise. 22

Appendix A. Moored C-T Time Series Figures 23

Figure A1. Temperature, conductivity and salinity from MicroCAT SBE-37 SN 3617 deployed at 7 m on the WHOTS-12 mooring. Pre-deployment calibration information was used. 24

Figure A2. Temperature, conductivity and salinity from MicroCAT SBE-37 SN 6893 deployed at 15 m on the WHOTS-12 mooring. Pre-deployment calibration information was used. Nominal pressure to calculate salinity. 25

Figure A3. Temperature, conductivity and salinity from MicroCAT SBE-37 SN 6894 deployed at 25 m on the WHOTS-12 mooring. Pre-deployment calibration information was used. Nominal pressure to calculate salinity. 26

Figure A4. Temperature, conductivity and salinity from MicroCAT SBE-37 SN 6895 deployed at 35 m on the WHOTS-12 mooring. Pre-deployment calibration information was used. Nominal pressure to calculate salinity. 27

Figure A5. Temperature, conductivity and salinity from MicroCAT SBE-37 SN 6896 deployed at 40 m on the WHOTS-12 mooring. Pre-deployment calibration information was used. Nominal pressure to calculate salinity. 28

Figure A6. Pressure, temperature, conductivity and salinity from MicroCAT SBE-37 SN 6887 deployed at 45 m on the WHOTS-12 mooring. Pre-deployment calibration information was used. 29

Figure A7. Temperature, conductivity and salinity from MicroCAT SBE-37 SN 6897 deployed at 50 m on the WHOTS-12 mooring. Pre-deployment calibration information was used. Nominal pressure to calculate salinity. 30

Figure A8. Temperature, conductivity and salinity from MicroCAT SBE-37 SN 6898 deployed at 55 m on the WHOTS-12 mooring. Pre-deployment calibration information was used. Nominal pressure to calculate salinity. 31

Figure A9. Temperature, conductivity and salinity from MicroCAT SBE-37 SN 6899 deployed at 65 m on the WHOTS-12 mooring. Pre-deployment calibration information was used. Nominal pressure to calculate salinity. 32

Figure A10. Temperature, conductivity and salinity from MicroCAT SBE-37 SN 3618 deployed at 75 m on the WHOTS-12 mooring. Pre-deployment calibration information was used. Nominal pressure to calculate salinity. 33

Figure A11. Pressure, temperature, conductivity and salinity from MicroCAT SBE-37 SN 3634 deployed at 85 m on the WHOTS-12 mooring. Pre-deployment calibration information was used. 34

Figure A12. Temperature, conductivity and salinity from MicroCAT SBE-37 SN 3670 deployed at 95 m on the WHOTS-12 mooring. Pre-deployment calibration information was used. Nominal pressure to calculate salinity. 35

Figure A13. Pressure, temperature, conductivity and salinity from MicroCAT SBE-37 SN 6889 deployed at 105 m on the WHOTS-12 mooring. Pre-deployment calibration information was used. 36

Figure A14. Pressure, temperature, conductivity and salinity from MicroCAT SBE-37 SN 6890 deployed at 120 m on the WHOTS-12 mooring. Pre-deployment calibration information was used. 37

Figure A15. Pressure, temperature, conductivity and salinity from experimental MicroCAT SBE-37 SN 13584 deployed at 134 m on the WHOTS-12 mooring. Pre-deployment calibration information was used. 38

Figure A16. Pressure, temperature, conductivity and salinity from MicroCAT SBE-37 SN 6888 deployed at 135 m on the WHOTS-12 mooring. Pre-deployment calibration information was used. 39

Figure A17. Pressure, temperature, conductivity and salinity from experimental MicroCAT SBE-37 SN 13585 deployed at 136 m on the WHOTS-12 mooring. Pre-deployment calibration information was used. 40

Figure A18. Pressure, temperature, conductivity and salinity from experimental MicroCAT SBE-37 SN 13586 deployed at 154 m on the WHOTS-12 mooring. Pre-deployment calibration information was used. 41

Figure A19. Pressure, temperature, conductivity and salinity from MicroCAT SBE-37 SN 6891 deployed at 155 m on the WHOTS-12 mooring. Pre-deployment calibration information was used. 42

Figure A20. Pressure, temperature, conductivity and salinity from MicroCAT SBE-37 SN 10602 deployed at 35 m above the bottom on the WHOTS-12 mooring. Pre-deployment calibration information was used. 43

Figure A21. Temperature, conductivity and salinity from SeaCAT SBE-16 SN 9988 deployed at 35 m above the bottom on the WHOTS-12 mooring. Pre-deployment calibration information was used. Nominal pressure to calculate salinity. 44

Appendix B. CTD Profiles 45

Figure B1. Profiles of 2 Hz temperature, salinity, potential density and oxygen data during the CTD cast 1 at station 20. The glitches above 5 dbar include data when the CTD pumps were not on, and will be removed during processing. 46

Figure B2. Profiles of 2 Hz temperature, conductivity, salinity, and oxygen data during S50C1 and S50C2. 47

Figure B3. Profiles of 2 Hz temperature, conductivity, salinity, and oxygen data during S50C3 and S50C4. 48

Figure B4. Profiles of 2 Hz temperature, conductivity, salinity, and oxygen data during S50C5 and S52C1. 49

Figure B5. Profiles of 2 Hz temperature, conductivity, salinity, and oxygen data during S52C2 and S52C3. 50

Figure B6. Profiles of 2 Hz temperature, conductivity, salinity, and oxygen data during S52C4. 51

Appendix C. WHOTS-13 Weather and Currents Weather During the WHOTS-13 cruise, Station ALOHA was under the influence of the eastern North Pacific high pressure system, and the associated east-northeasterly trade winds (Fig. C1). Conditions during the WHOTS-13 deployment on June 26 th -27 th were favorable, with 10-15 kts NE winds and 2-3 m waves from NE (Fig. C2). Figure C1. The NOAA/NCEP GFS surface wind and sea level pressure analysis for the central-eastern North Pacific, valid for 18Z on June 26 th, 2016. 52

Figure C2. Significant wave height from the NOAA Wave Watch III forecast on June 27 th, 2016, 12:00Z. Weather conditions were favorable during 28 th through the 30 th, with NE wind speeds of 10-15 kts with occasional higher gusts. Winds were 12 kt from the east on June 29 th -30 th during the WHOTS-12 recovery, increasing to between 15 and 18 kt on June 30 th July 2 nd. Currents The shipboard ADCP CODAS real-time data management, processing and display system software was used to monitor the currents during the cruise. Near-surface currents were up to 1 kt westward during transit to Station ALOHA, turning NNEward upon arrival to Station ALOHA, and fluctuating the rest of the cruise (Fig. C3). There was a nearly stationary anticyclonic eddy east of ALOHA (Fig. C4), suggesting a possible increasing geostrophic flow towards the NW, although a combination of internal semidiurnal and diurnal tides, along with near-inertial oscillations, were more noticeable especially in vertical shear (Fig. C5). 53

Figure C3. History of shipboard 75 khz ADCP (OS75bb) current measurements from June 26 th, 23:48z (left) and from June 30 th, 19:19z (right) averaged over depths from 31 to 71 m. Water temperature at the hull transducer depth is indicated by vector color. Figure C4. Sea surface height from the NRL 1/12 th degree HYCOM analysis for 00Z on June 26 th, 2016 (left) and June 29 th (right). 54

Figure C5. Shipboard 75 khz ADCP (OS75bb) currents on June 30 th as a function of depth and time. 55