Active microwave remote sensing techniques are under 

 development and test to determine the feasibility of employing these 

 techniques on aircraft and satellites for accurate measurements of 

 the dynamic topography of the ocean surface, mean sea level, sea 

 state and sea ice conditions, and sea surface wind speeds and 

 directions. A vital part of these development programs is the 

 recognition of the need for "sea-truth" data, independent 

 observations of the sea state conditions from ships or off-shore 

 ocean platforms required for correlation with the output signals 

 from the remote sensor instruments. 



A new sensor system is also being developed for use in the Coast 

 Guard's program of aerial pollution surveillance for oil and 

 hazardous substances. This program involves twice-weekly aerial 

 flights over U.S. territorial waters and the contiguous zone, and 

 random flights over prohibited zones as designated by the 

 Convention on the Prevention of the Pollution of the Sea by Oil, as 

 amended. In port areas handling over 10 million tons of petroleum 

 per year, and in other designated areas, daily aerial flights are 

 conducted over the harbors and at least ten miles out over the 

 approach channels. 



The Coast Guard is supporting the development of an advanced 

 all-weather, day-night aerial oil-pollution surveillance system to be 

 used in this program. The system will integrate infrared and 

 ultraviolet scanning photometers with side-looking radar and dual- 

 frequency passive microwave radiometers to detect oil slicks and 

 map their extent and thickness. The Transportation Systems Center 

 of the Department of Transportation is also developing an airborne 

 laser-excitation device for the Coast Guard to permit determination 

 of the type of spilled oil. 



Aircraft Platforms 



Aircraft play an important role as platforms from which 

 experiments are carried out in the field to establish the feasibility or 

 determine the utility of employing various types of remote sensing 

 techniques to obtain information on marine parameters, processes, 

 and phenomena. Over 50 aircraft remote-sensing missions were 

 flown in 1972 by the four aircraft operated by the NASA Johnson 

 Space Center. Thirty-five of these missions were in support of 

 coastal zone experiments dealing with the use of remote sensing in 

 pollution studies in bays, estuaries, and nearshore areas. Sixteen of 

 the aircraft coastal-zone missions werein support of EarthResources 

 Technology Satellite (ERTS-1) investigations: six were flown over 

 the Great Lakes area to evaluate the performance of passive 

 microwave remote sensors as lake ice monitors, and six were flown 

 over the North Atlantic Ocean and the Gulf of Mexico to support the 

 acquisition of sea-state data with passive and active microwave 

 sensors. An ocean-color mission was flown over the eastern Gulf of 



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