Other dye experiments should be made at higher altitudes with 

 photographs made from various angles using the 0.560-micron band. 

 Experiments could be extended to areas of swift currents using air- 

 dropped, sintered dye bricks. If high-altitude experiments show good 

 contrast in the 0.560-micron band then experiments at orbital altitudes 

 should be attempted. 



Microwave Radiometers 



Description 



A microwave radiometer detects electromagnetic energy emitted in 

 the microwave region. The energy available in this region of the spec- 

 trum is about one ten-thousandth of that available in the infrared 

 region; however, powerful amplifiers are used for microwave frequen- 

 cies. Theoretically, microwaves can penetrate clouds to measure ocean 

 temperature . 



Four microwave radiometers were operated over the Gulf Stream on 

 the flight tracks shown in figures 4 and 8 and during the thermal grid 

 flight track (figures 6 and 7)» In addition the radiometers were used 

 at a variety of altitudes, weather, roll, and day-night tests over 

 water. The radiometers were operated with vertical polarization and 

 a 45° grazing angle. 



Results 



The 9«3~GH Z radiometer failed to operate during the experiment, 

 the 34.0-GH z radiometer was too noisy to be read, and the magnetic 

 tape recording system was unsatisfactory. Judging from the strip 

 chart, the 15^8- and 22.2-GH z radiometers did not respond to the tem- 

 perature change across the northern wall of the Gulf Stream. Both 

 radiometers, strongly affected by roll motion, deflected toward higher 

 radiation levels when the aircraft turned, when flown over land masses, 

 and when flown into rain. In the altitude range of 150 to 4,120 meters 

 the 15.8- and 22.2-GHz radiometers were increasingly deflected toward 

 higher radiation levels with increased altitude. The 22.2-GH z radiome- 

 ter, which operates at a dipole resonance line of water vapor, was 

 deflected less than the 15«8-GH Z radiometer. 



Conclusions 



The microwave experiment was incomplete owing to recurrent fail- 

 ures in the system. The experiment should be repeated when the micro- 

 wave system has been repaired and tested. 



Wave Detection 



Description 



The objective of the wave experiment was to compare sea surface 

 characteristics measured by the scatterometer, the wave staff, and the 

 radar wave profiler. The wave staff is an electrical resistance-wire 



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