dome. A chart of the dynamic topography 

 located the top of the dome at about 15 0N., 

 950 W., but the area of coolest surface water 

 was somewhat southwest of this; measurements 

 of surface current by geomagnetic electro- 

 kinetograph (GEK) were consistent with the 

 dynamic topography. 



Brandhorst (1958) concluded: From the figures 

 it can be deduced that this "dome" is associated with 

 strong current, circling counterclockwise in the Gulf. 

 It is remarkable that the cool surface water does not 

 coincide with the center of the dome. 



OBSERVATIONS ON CRUISE 



TO-58-1, EXPEDITION SCOT (MAY 



AND JUNE 1958) 



The Gulf of Tehuantepec was surveyed from 

 May 27 through June 2, 1958. Figure 3 shows 

 the ship's track, observation points, and sec- 

 tion lines. The weather was generally fine, 

 the wind mainly from the north and northwest 

 and light, except at station 82 where a northerly 

 at Beaufort force 5 was encountered on May 29. 



To facilitate comparison of charts and 

 sections for this and the other cruises, it 



should be noted that bathythermograph (BT) 

 observations between stations are numbered 

 where necessary as x - y where x is the 

 number of the last station and y indicates the 

 order of the observation in the series made 

 between stations x and x + 1: e.g., 81-2, the 

 second BT after station 81; 0-13, the thirteenth 

 BT between the beginning of the cruise and 

 station 1. 



Section A-A, as shown in figure 3 and on 

 similar charts for later cruises, runs more 

 or less parallel to the edge of the Continental 

 Shelf, which extends further south in the east- 

 ern part of the Gulf than in the western. 

 Section B-B is a meridional section along 

 the axis of Chivela Pass. 



Horizontal distributions of properties 



The charts in figure 4 show horizontal 

 distributions of (A) dynamic height anomalies 

 and surface current by GEK, (B) surface 

 temperature, (C) surface salinity, (D) surface 

 oxygen, (E) inorganic phosphorus (phosphate) 

 at 30 m., and (F) zooplankton and micronekton. 

 Figure 5 gives similar data for surface 

 chlorophyll a and productivity. 



Figure 3.--Track chart of cruise TO-58-1, Expedition SCOT, in the Gulf of Tehuantepec. 



