at Greenbelt, Maryland and to the National Weather Satellite Center 

 at Suitland, Maryland where they were referenced and made available 

 for historical use in strip mosaics. 



The Automatic Picture Transmission System (APTS) provided similar 

 cloud mapping photographs of somewhat lower resolution to local users 

 who employed a simple inexpensive ground station. Since the coverage 

 was the same as the AVCS and the data were not catalogued. Nimbus 1 

 and 2 APTS pictures are not considered of oceanographic use. 



The AVCS provided pictorial information of daytime conditions. 

 At nighttime, the High Resolution Infrared Radiometer (HRIR) system 

 provided a continuous measurement of the earth's thermal radiation. 

 These data were stored on tape in the spacecraft and read simultaneously 

 with the AVCS pictures to the CDA sites in Alaska or North Carolina. 



The Medium Resolution Infrared Radiometer (MRIR) used on Nimbus 

 2 was a five-channel camera system designed to give the heat balance 

 of the earth-atmosphere system, the water vapor distribution, surface 

 or near surface temperatures, and seasonal changes of stratospheric 

 temperature distribution. 



A number of catalogs and users guides are available for the Nimbus 



satellites and are listed in the bibliography section of this report. 



These catalogs and guides are available from NASA at the following 



address: 



National Space Science Data Center 

 Goddard Space Flight Center 

 Code 601 

 Greenbelt, Maryland 20771 



HRIR data requests will be fulfilled by making reproductions from 

 transparencies which are stored at the National Space Science Data 



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