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OCEANOGRAPHY

CTD data were collected by a self-recording, self-powered, multiparametric probe (Sea-Bird MICROCAT model SBE37-SM) lowered at a velocity of 0.8-0.9 m/s, with a sampling interval of 5s (4, Fig. 4). CTD row data were processed on board by standard SeaBird programs.

A Sea-Bird SEACAT SBE 21 Thermosalinograph positioned very close to the ship bow with a flow rate of about 1 l/s collected continous real time subsurface CTD data. Two hull mounted Sea-Bird SBE38 thermometers provided additional on-going data.

Ten Sippican T7, T5 and Fast Deep expendable bathytermograph (XBT) probes were launched (MK-12 interface) during the cruise (5, Fig. 4). Sound velocity was computed assuming salinity of 30 psu in the Strait of Magellan, 34 psu and 34.30 psu for the shallower and more distal stations in the Pacific Ocean, being also checked against the Thermosalinograph real-time surface and CTD casts.

The Sound Velocity data from the acquired XBT and CTD profiles were immediately imported into the PDS-2000 software for multibeam data corrections.

A Teledyne RDI ADCP Ocean Surveyor Hull-Mounted 75kHz, four 30°beam, phased array ADCP system collected current velocity data in the water column. The system was interfaced to the attitude sensors (PHINS) and other real time data by the PDS-2000 navigation software. Two configuration (large and narrow bandwidth, also with bottom tracking, 16m bins) were used for shallow and deep waters.

An AWS (data acquisition controller developed at OGS) interfaced two R.M.Young meteorological sensor sets, mounted at about 22.5 m above sea level, collecting wind speed and direction, air temperature, atmospheric pressure, relative humidity, sea surface temperature and position data at a sampling rate of 1 minute. The data strings were made available trough the PDS-2000 navigation system.


Table 4: CTD Stations positions.
STATION DATE LAT LON DEPTH COMMENT
CTD1 2004-04-03T15:56:23 -53:43.43 -70:52.02 510  
CTD2 2004-04-04T05:22:05 -53:12.83 -73:18.54 1130  
CTD3 2004-04-04 -52:30.35 -75:35.30 1150 Failed
CTD4 2004-04-05T14:52:46 -52:40.44 -75:59.91 2800  



Table 5: XBT Stations positions.
STATION DATE LAT LON TYPE TDEPTH
XBT1 2004-04-03 -53:29.84 -72:41.17 T7 760
XBT2 2004-04-04 -52:53.49 -74:05.04 T7 760
XBT3 2004-04-04 -52:30.24 -75:35.94 T5 1830
XBT4 2004-04-04 -52:30.24 -75:35.94 FD 1000
XBT5 2004-04-04 -52:43.11 -75:53.99 T5 1830
XBT6 2004-04-05 -52:34.03 -75:54.36 FD 1000
XBT7 2004-04-05 -52:58.51 -75:52.41 T7 760
XBT8 2004-04-05 -53: 4.99 -75:51.27 T7 760
XBT9 2004-04-05 -52:42.03 -75:35.54 T7 760
XBT10 2004-04-06 -53:02.14 -75:35.25 T7 760



next up previous contents
Next: MISCELLANEOUS Up: MATERIALS AND METHODS Previous: GRAVIMETRY   Contents
2007-10-30