CTD and ADCP data were acquired between 1991 and 1993 in the portion of the Gaspé Current between Les Méchins and Gros-Morne by researcher Pierre Larouche. These measurements are part of a study on the detection of coastal currents by remote sensing carried out by Larouche in 1996. More recently, this unique set of data allowed the master's student in oceanography, Théau Leclercq, to complete his research project concerning observations of upwellings and downwellings on the edge of the Gaspé Current, of which Pierre Larouche is the co-director.
The research project has been published:
Leclercq, T., Chavanne C., Larouche P. 2023. Upwellings and downwellings on the edge of the Gaspé Current: Observations and processes. Regional Studies in Marine Science. https://doi.org/10.1016/j.rsma.2023.103325
The in-situ data come from 4 expeditions carried out between 1991 and 1993. These expeditions enabled the acquisition of 12 transects of ADCP (Teledyne Workhorse Sentinel) data on which CTD stations are spread. Temperature, salinity, and pressure (T, S, P) data were acquired with a Guildline 8715 CTD. The study of small-scale structures with CTD was carried out with a V-fin wave profiler technique for the last expedition. The current data obtained by ADCP (150 kHz transducers for the first expedition, and 600 kHz for the other 3) come from the zone where the speed of the Gaspé current is maximum, and where instabilities are developed (between Les Méchins and Gros-Morne).
For the first mission, it took place from 20 to 27 September 1991, allowing the harvesting of 93 CTD stations and 19 ADCP transects. The low frequency of ADCP pings (150 kHz) allowed the acquisition of the bottom track.
For the second mission, it took place from 16 to 23 May 1992 during which 106 CTD stations were acquired. However, only 105 files are available, as the data from station no. 68 has been lost. This mission also includes 11 ADCP data transects (600 kHz).
The third mission took place from July 30 to August 7, 1992, and 74 profiles were collected, including a station that was lost (station no. 211), as well as 14 ADCP transects (600 kHz).
For the last mission, it took place from 5 to 12 June 1993 during which 39 CTD stations, 47 V-fin CTD files, and 38 ADCP data files (600 kHz) were collected.
CTD profiles data from all missions underwent quality control, filtered with an 11-point median filter, and then averaged per meter. All of these tests as well as the data are transcribed in ODF format.
ADCP data for all missions are raw and in DAT format, readable with any text editor.
CTD-VFin data from the June 1993 mission are raw and in PRN format, readable with any text editor.
A report of each mission presenting the CTD profile data was published on the DFO website by Mr. Larouche:
Some of these data are already archived at the Maurice Lamontagne Institute (CTD casts from the May 1992, August 1992 and June 1993 missions).
10.26071/ogsl-9acdc006-20cb
