The physical oceanography of the Gulf of Thailand, Naga Expedition; Bathythermograph (BT) temperature observations in the Timor sea, Naga Expedition, Cruise S11
- Author(s): Robinson, Margaret K
- et al.
The Research Vessel Stranger of the Scripps Institution of Oceanography, University of California, San Diego, was engaged in the Naga Expedition in the Gulf of Thailand and the South China Sea during the period of October, 1959, to December, 1960. The expedition was jointly sponsored by the Governments of South Viet Nam, Thailand and the United States of America. It had a two-fold purpose; to collect oceanographic, biological and fisheries data and material and to train scientists and technicians from Thailand and South Viet Nam in oceanography and marine biology. This report is a description of the oceanographic environment in the Gulf of Thailand derived from oceanographic and meteorological data collected for the most part on six cruises in the Gulf between October, 1959, and December, 1960. The cruise plans for the Gulf of Thailand were designed to investigate systematically the distribution and variability of the physical properties of the Gulf waters. The station plan consisted of stations located 30 to 40 miles apart on five parallel lines running perpendicular to the east and west coasts of the Gulf. The lines were 60 to 90 miles apart. Figure 1 is a composite plan for the five Gulf cruises which made complete hydrographic measurements. The stations were numbered chronologically on each cruise. Thus, stations at approximately the same location have different numbers on each of the cruises. Within the limits of navigation the primary stations on each line were at the same location on each cruise. The following physical oceanographic data were collected at each station; reversing thermometer temperatures, salinity and oxygen determinations at standard levels—0, 10, 20, 30 and 50 m—as depth allowed and bathythermograph (BT) temperature observations. The latter were also taken midway between regular stations and at intervals parallel to shore between station lines. Meteorological observations, including wind, air temperature and sea condition, were taken at the time of each BT. Station data and a description of the physical and chemical methods may be found in Faughn, NAGA report, volume 1. The R. V. Stranger of the Scripps Institution of Oceanography carried out an extensive geophysical survey of the Timor Sea between March 29 and April 24,1961, (van Andel and Veevers, 1967) following the completion of the major oceanographic observational programs in the Gulf of Thailand and the South China Sea. During the survey, closely spaced bathythermograph (BT) temperature and wind velocity observations were made. Observed wind velocities, vertical temperature sections along the cruise tracks and horizontal distributions of temperature at standard depth levels based on BT data are the subject of this report. These observations provide a detailed description of the temperature structure of the Timor Sea and complement the more general one given by Wytrki (1961).