CURRENTS 



Current measurements were made at seven locations In the upper Persian 

 Gulf, seven locations in the lower Persian Gulf, and eight locations in the Strait 

 of Hormuz. Figure B-l (appendix B) shows the station locations and the current 

 directions. Figures B-2 through B-7 show the current data in the upper Persian 

 Gulf during 1960; Figures B-8 through B- 19 show current data in the lower Persian 

 Gulf and the Strait of Hormuz during 1961 . 



Time of observation, direction, and speed of the current flow are indicated 

 by an arrow on a horizontal time line . Direction is shown by the clockwise angle 

 the arrow makes with vertical and the length of the arrow indicates the current 

 velocity. 



In the upper Persian Gulf, low velocities were usually recorded at high and 

 low tide; velocities decreased slightly with depth at all stations. Current direc- 

 tion was the same at all depths except at station 23 in the south where the surface, 

 mid-depth, and bottom currents (during a 6-hour period) were moving in a 330°, 

 270°, and 225 p direction, respectively. 



In the lower Persian Gulf, when currents at northern stations (numbers 5, 13, 

 22) moved in a northwest direction, currents at southern stations (numbers 9 and 

 18) flowed to the south; when the tide changed the current reversed and moved in 

 the opposite direction . Velocities generally decreased slightly from surface to 

 bottom . At stations 7 and 20, the direction was not consistent, and at times, the 

 measurements at the three depths differed considerably in direction and speed. 



In the Strait of Hormuz, water flowed into the Persian Gulf during flood and 

 out during ebb . At stations 29 and 30, velocities decreased with depth; at sta- 

 tions 34, 35, and 36, surface, mid-depth, and bottom currents generally were not 

 in phase, and at times water at one level was moving in opposite directions to that 

 in other levels. At station 33, currents were considerably stronger than at station 

 34. In general, velocity decreased with depth, and direction showed water flow- 

 ing into Clarence Strait during high tide and in the opposite direction during low 

 tide . At station 40, current speed decreased with depth; direction was north during 

 flood and south during ebb. 



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