Greater emphasis will be placed on the development and testing of 

 multifrequency passive and active microwave remote sensing 

 techniques to take advantage of their ability to acquire data under 

 most adverse weather conditions, both day and night. The first 

 opportunity for such tests will be during the conduct of the manned 

 SKYLAB mission scheduled to begin in mid-May 1973. The 

 performance of an active microwave scatterometer and pulsed radar 

 altimeter will be monitored and evaluated to see how well these 

 instruments can provide data on sea state conditions and altitude 

 measurements of ocean surface topography on a near-global basis 

 activities. Seagoing assets consist of 38 ships, of which 17 are at 

 the design and performance characteristics of similar types of 

 remote sensors for use in satellite-borne demonstration 

 experiments. 



The first attempt to apply geodetic satellite technology to 

 measurements of ocean surface topography on a near global basis 

 will be made in the latter part of 1974 with the launching of NASA's 

 GEOS-C satellite. This satellite will carry a pulsed radar altimeter 

 capable of measuring the distance between the satellite and the 

 surface of the ocean with a precision of about 50 centimeters. It is 

 expected that relative differences in ocean surface topography of the 

 order of one meter or larger will be detected and mapped during the 

 one-year anticipated lifetime of the altimeter. 



Initial planning is underway to take advantage of the Space 

 Shuttle as a platform from which astronauts can assemble and place 

 in orbit about the earth very large (100-meter diameter) antennas 

 which are required to achieve the high spatial resolutions required of 

 passive microwave remote sensors for monitoring coastal zone 

 processes under day-night, near all-weather conditions. 

 Consideration is also being given to active microwave remote 

 sensing techniques that can provide images of waves impinging on 

 the shores under day-night, near all-weather conditions from high 

 altitude aircraft or satellites. The utilization of geostationary 

 satellites as oceanographic data acquisition platforms will also be 

 investigated. 



The planning of many of the future programs will be accomplished 

 on a cooperative basis by the agencies that are in the best position to 

 assume responsibilities for the engineering and technological 

 aspects of the programs and the agencies who are in the best position 

 to judge the utility of the data products to be obtained by the 

 advanced oceanographic data acquisition systems. It is anticipated 

 that greater use will be made of aircraft remote sensing techniques in 

 support of the Marine Ecosystems Analysis (MESA) program, 

 NORPAX, and AIDJEX. 



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