Mexico in support of an ERTS-1 investigation of the Mississippi 

 Sound. 



A C-54 aircraft operated by NASA's Wallops Station was used to 

 support several cooperative experiments with the U.S. Navy, the 

 Army Corps of Engineers, the U.S. Coast Guard, the Environmental 

 Protection Agency, the University of Delaware, and the Virginia 

 Institute of Marine Sciences. These efforts were concerned with uses 

 of passive microwave radiometers and multi-spectral band cameras 

 to measure the amount of oil in slicks associated with oil spills. 

 Photography delineated the boundary of the spills; the microwave 

 radiometers provided temperature variations which could be 

 correlated with the variations in oil thickness. 



A joint experiment was carried out by NASA and Navy 

 investigators using the Naval Research Laboratory narrow-pulse 

 radar altimeter on the NASA Wallops aircraft to obtain sea 

 roughness measurements. Comparison of the radar altimeter with 

 measurements of sea-state conditions made with an accurate laser 

 profilometer on the aircraft indicated that the use of a narrow-pulse 

 radar system as a remote sensor for sea state measurements was 

 feasible. 



Low-altitude aircraft missions were flown over Chesapeake Bay 

 and Lake Ontario in support of performance evaluation tests of a 

 laser remote-sensing system designed by NASA's Wallops Station to 

 obtain measurements of algae and phytoplankton concentrations at 

 and near the surface of the water. The measurement technique makes 

 use of an intense pulsed laser beam to excite fluorescence emissions 

 and a detector to measure the strength of the emissions, which 

 should be proportional to the concentration of the algae and 

 phytoplankton. The data obtained were compared with surface data 

 provided by the Environmental Protection Agency (EPA) and by 

 NOAA. 



The NASA Ames Research Center Convair 990 jet aircraft carried 

 out flights in the Arctic region in support of experiments to assess 

 the utility of a passive microwave scanning radiometer as a near all- 

 weather sea-ice remote sensor. Missions were flown during March 

 1972 to take advantage of the presence of scientists on sea ice who 

 were participating in the AIDJEX pilot experiment in the Beaufort 

 Sea. Measurements were made on a day when visibility was good 

 and on a subsequent day when the surface of the ice was obscured by 

 clouds. The capability of employing passive microwave radiometers 

 to obtain information on the spatial and time variations of the 

 distributions of first-year and multi-year ice under virtual all- 

 weather conditions was verified by comparison with information on 

 sea-ice conditions provided by the AIDJEX scientists. A series of 

 Convair 990 flights over the Great Lakes during early spring 

 demonstrated the ability of the passive microwave radiometer to 

 map the distribution of fresh-water thin ice and thick ice. 



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