Results of previous investigations by other workers have shown wide variations be- 

 tween radiation measurements of micro-surface temperatures and conventional bucket tem- 

 perature measurements when air and sea temperature differences are large, moisture con- 

 tent of atmosphere is high, or when relatively little mixing is occurring along air sea inter- 

 face. 



Weather conditions and temperature variations during the period of observation were as 

 follows: Air temperatures varied only 6.0" F. (54.0° to 60.0°F), during the 48 hour period 

 and sea surface temperatures, from bucket thermometer, varied 0.9°F (54.6° to 55.5°F). 

 Relative humidity, 50 - 90%; wind speed, 7-34 knots; average speed approximately 20 knots; 

 prevailing wind direction from west; skies overcast; rainfall approximately 0.7 inches. 



Waves and swells ranged in height from 2-9 feet during period of observation. 



Surface temperatures from radiation and bucket thermometers were, in most in- 

 stances, within 0.5°F, the accuracy to which radiation thermometer can be read due to the 

 2°F scale division of readout meter. 



Temperature differences of 4.0° - 4.5°F between IRT and bucket thermometer meas- 

 urements were experienced by lowering 60 cycle power supply to 58.4 cycles per second. 



Plots of radiation minus bucket temperature measurements versus time and air minus 

 bucket temperature versus time show no correlation. 



Measurements of sea surface temperatures using infrared radiation thermometer 

 under conditions described, were well within the absolute accuracy limits of ±2.0°F specified 

 by manufacturer. The accuracy obtained under conditions described was possibly due to 

 rapid mixing of surface layer and the small air-sea temperature difference. 



PRESENT PRCXGIRAM 



The area covered on the flight path, and drift bottle and sea bed drifter release points 

 are shown in Figure 2. Aircraft assistance for areas east and west of Southwest Pass is pro- 

 vided by the Pensacola Naval Air Station, Pensacola, Florida, and the U. S. Coast Guard Air 

 Detachment, Biloxi, Mississippi, respectively. Total flying time required is approximately 

 16 hours. 



Flights are scheduled for coverage of the entire area during a 48 hour period when- 

 ever possible. However, we have been unable to accomplish this thus far, due to weather, 

 available aircraft, etc. 



Simultaneous measurements of surface temperature and meteorological conditions 

 are obtained at two points over northeastern sector. 



Surface and sub-surface temperature data along with other pertinent meteorological 

 data are furnished by the U. S. Fish and Wildlife Service in Galveston, Texas from their 



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