Page 



4. Salinity profile to 600 m. based on data from hydrocast stations 7-22, TO-60-1. Con- 



tour interval: 0.10%„. Note the oxygen minimum layer, as in figure 3 10 



5. T-S curves {on a 8^ field) of stations from CalCOFI cruise 6004-B. Curves from sta- 



tions on line 1 20, off Point San Eugerdo, are of "less transitional" California Current 

 water than those from line 143, off Magdalena Bay which are "somewhat more tran- 

 sitional." The curve of station 143.60 probably shows influence of central Pacific 

 water at the surface 11 



6. T-S curves from stations online 153 (cruise 6004- B) and five stations (16, 20, 22, 25, 



and 27) of cruise TO-60-1; these curves represent "most transitional" California 

 Current water (fig, 5) 12 



7. T-S curves from several stations on cruise TO-60-1 that represent equatorial Pacific 



water near its northern limit (p. 26) 13 



8. T-S curves from several stations on cruise TO-60-1 that represent Gulf water. The 



curve of station 1 suggests the influence of water of lower salinity above the density 

 surface of 360 cl. ton-1 14 



9. Distribution of surface isotherms (contour interval: 0.5° C.) at front 5, off Cape San 



Lucas, Lower California, from the initial thermograph survey (0956 hrs. 19 Apr. 

 till 1235 hrs. 20 Apr. 1961), the track of which is shown. — o — time check; — • — 

 temperature check; speculative contour 16 



10. Distribution of surface isotherms (contour interval: 0.5° C.) at front 5, off Cape San 



Lucas, Lower California, from the final thermograph survey (2346 hrs. 23 Apr. till 



1105+ hrs. 24 Apr. 1961). — o — time check; — • — temperature check; speculative 



contour 17 



11. Distribution of surface isotherms (contour interval: 0.5° C.) at front 3, off Cape San 



Lucas, Lower California, from a thermograph survey (0105 hrs. till 1600+ hrs. 



22 May I960). — o — time check; — • — temperature check; speculative contour. 18 



12. Apparent paths of four drogues released in the middle or slightly on the warm side 



of front 5 on 21 Apr. 1961. Track changes were based on subsequent sightings, 

 the times of which are given where space allows. The temperature (°C.) of the 



surface water at time of sighting is also given. •■ drogues with parachute 



at 50 m. ►• — drogues with parachute at 5m 19 



13. Surface currents based on nine GEK measurements made on 21 Apr. 1961. Currents 



are shown vectorially, the number above the vector being the velocity in cm. 



secT , that below being the bearing in °T. Superimposed are the track ( ) and 



surface isotherms ( ,°C.) from the thermograph records 20 



14. Tracks of three BT passes made at front 5 on 20-21 Apr. 1961. The third pass (-,-•-) 



is the one discussed in the text because it covers the greatest range of surface tem- 

 perature, the isotherm contours of which are shown ( ,°C.) 21 



15. The temperature profile from BT pass no. 3 across front 5 (21 Apr. 1961). Cross- 



hatching shows water that is practically isothermal vertically. The five main bodies 



of such water (I- V) are discussed in the text, c = cool side; w = warm side 22 



16. Chart showing starting positions of hydrocasts (5B1 - 3; 5E1 - 3), oblique net tows (5A1-3; 



5F1-3), nekton and surface net tows (5D1-3), and Clarke-Bumpus net tows (5C1-3). 

 Surface temperature (°C.) at the start of an observation is given below the station 

 number . . ., 23 



17. Temperature profile and temperature-depth curves for the first (B) triplet of hydro- 



casts at front 5 (22 Apr. 1961). c = cool side; m = middle; w = warm side; 



• = Nansen bottle depths in profile 24 



18. Temperature profile and temperature -depth curves for the second E triplet of hydro- 



casts at front 5 (23 Apr. 1961). c = cool side; m = middle; w = warm side; 



• = Nansen bottle depths in profile 25 



