with the display in real-time. Thus, given a real-time data display 

 capability, an individual could modify and refine a desired product 

 in response to a particular requirement or objective. The atlas 

 provides access to large data bases, such as the NODC global ocean 

 station and bathythermograph files. Basically, this display consists 

 of a large data base structured for rapid retrieval, a display inte- 

 grated program library which allows for great flexibility and a wide 

 spectrum of use applications, and computer hardware which includes a 

 computer driven cathode-ray tube display unit, a sufficiently large 

 data storage device. The accomplishments to date include restructured 

 ocean station and bathythermograph files. A number of real benefits 

 have already been realized as a consequence of these accompli sliments: 

 (1) the Undersea Surveillance Oceanographic Center (USOC) is making 

 use of a sound velocity file extracted from the North Atlantic Ocean 

 station file, (2) NODC has used the files to satisfy data requests 

 with substantia] savings in cost and time, (3) the Fleet Numerical 

 Weather Central, Monterey (FLl^aJMlv'HACF.N) has used the file to extract 

 data which were not previously included in their data bank. 



III. DESCRIPTION OF THE LIVE ATLAS 



As mentioned earlier, the live atlas consists of a compact data 

 base, a computerized visual display, and a computer software package 

 which enables accessing, displaying, and/or manipulating the data in 

 real-time. A schematic representation of the live atlas hardware is 

 shown in figure 1. 



A. Ocean Station Files 



The North Atlantic Ocean station file has been restructured 

 from a binary coded decimal line image format to a variable length 

 free field binary format. This technique, along with high density 

 storage, has allowed the reduction in the physical size of the file 

 from 22 to less than a single reel of magnetic tape. As a result, 

 the file scanning time has been reduced from approximately 24 hours 

 to 4 minutes. Tlie NODC global ocean station file has been similarly 

 reduced in size without the omission of data. Data representing 

 approximately 350,000 ocean stations will be contained on a single 

 reel of magnetic tape. 



B. Bathythermograph 



A global file containing all current digitized mechanical 

 BT traces is contained on 1.25 reels of magnetic tape. Each BT is 

 fitted with a series of least square regression lines. The tempera- 

 ture and depth at the points of intersection are stored. In addition, 

 the temperature gradient between successive points and a goodness of 

 fit indicator of tlie line of regression are provided as is shown in 

 a printout of the data (figure 2). 



308 



