In winter, water temperature in Kuwait Harbor and vicinity varies 

 little either horizontally or vertically. The surface temperature ranges 

 from a low of about 56°F. in the southern and western portions of the 

 bay to nearly 60°F. just off Jazirat Faylakah. The difference between 

 the surface and bottom is of the same order of magnitude; a maximum 

 vertical temperature gradient of 3°F. was recorded at the mouth of 

 the harbor in a depth of 26 feet. 



This is quite in contrast to the summer conditions reported by Dr. 

 K. O. Emery for August 1948. Observations taken by him show surface 

 temperatures in excess of 90°F. and bottom temperatures of about 

 85°F. These temperatures result in a gradient of 5° to 7°F. in approxi- 

 mately 45 or 50 feet of water. The gradient increases markedly farther 

 east of Fahihil where bottom temperatures reach 75° to 77°F. in a depth 

 of about 75 feet. Development of this extremely warm surface layer 

 probably begins in April or May when the mean maximum air temper- 

 ature begins to show an appreciable increase. Also the general decrease 

 in cloudiness with the advent of spring provides for increased solar 

 heating (insolation) of surface waters. A reduction in frequency of 

 frontal passages with their typical gusty "sharaal" type winds is 

 another factor contributing to the development of a strong gradient 

 between the surface and bottom water through the spring and early 

 summer months. Without these squally "shamal" type winds, mixing 

 is reduced to a minimum. In autumn, beginning in October, the processes 

 are reversed. 



Even in winter, solar insolation frequently raises midafternoon air 

 temperatures to the seventies; thus it is reasonable to expect some 

 diurnal fluctuations in the water temperature near the surface. The 

 two time-depth sections taken in Kuwait Harbor in January and February 

 and one section taken off Fahihil in March illustrate well midwinter 

 diurnal warming of the surface waters (Figs. 4, 5, and 6, respectively). 

 These sections are based on BT observations taken at approximately 

 half- hourly intervals while drifting along the tracks shown in the 

 insets on Figure J ^"C. No drift chart is available for the February 

 observations, but the drifting boat started from approximately the 

 same position as that for the January observations. Bathythermograph 

 log sheets containing supplementary meteorological data for these 

 three series of observations have been reproduced in Table II. On 

 the cross sections all BT observations have been corrected in accordance 

 with procedures described in H. O. Pub. No. 614, "Processing Oceano- 

 graphic Data." 



Diurnal temperature ranges of 1.3° and 3.1°F. were recorded 

 at the surface for the two Kuwait Harbor series of observations; off 



