Ch. 7— Federal Programs for Collecting arid Managing Oceanographic Data • 261 



computer, in contrast to geophysical data which are 

 collected digitally in a relatively uniform manner. 



Bathymetry and Marine Boundary Data- 

 bases. — There are four kinds of data sets included 

 in this category: NOS Hydrographic Surveys 

 (NOS/HS), NOS Multi-beam EEZ Bathymetry 

 (NOS/MB), Gridded Global Bathymetry (GGB), 

 and Marine Boundary (MB). 



• The most valuable EEZ data sets in this group 

 are those from the National Ocean Service. 

 All NOS hydrographic surveys that are avail- 

 able in digital form are archived and merged 

 into an accessible database at NGDC . All four 

 data sets (except NOS/MB) are collecting data, 

 are all in digital form, and all are unedited. 

 NOS/MB data are aggregated, and NOS/HS 

 data are reformatted to be accessible by loca- 

 tion. (The NOS/MB data are "on hold" as 

 a result of classification.) All data sets are on 

 magnetic tape. 



• The time lag for reporting NOS/HS data is 

 about 2 years. All but the NOS/MB data are 

 made available to others on request. 



• The NOS/HS data are acquired at about 42 

 megabytes per year from the NOS. GGB was 

 a one-time data acquisition from academic and 

 DoD sources. 



• Annual increases in uses for NOS/HS and MB 

 data are estimated at 5 percent and GGB at 

 15 percent. (There is no EEZ multiple-beam 

 bathymetry on file at NGDC because of data 

 classification, and no acquisition is planned. 

 NGDC does plan to index the location of sur- 

 vey tracklines so that operators of multi-beam 

 systems can avoid duplication.) 



Problems with Bathymetric and Boundary 

 Data. — Transmission of survey data between NOS 

 and NGDC has been irregular over the years, pri- 

 marily because the digital versions of surveys have 

 not been important to the nautical charting effort 

 at NOS. Over the last 3 years, NGDC has made 

 a consistent effort to obtain and catalog a large 

 backlog of surveys stored at NOS headquarters. 

 Availability of other bathymetric data sets depends 

 on DoD classification policies. Marine boundary 

 data are available, though they need to be central- 

 ized to be readily accessible. NGDC has the U.S. 

 EEZ boundary points (produced by NOS) and the 

 outer continental shelf lease area boundary points 



(produced by USGS). NOS is compiling and dis- 

 tributing a detailed set of boundary points for the 

 U.S. coast; these data have not been submitted to 

 NGDC. 



Underway Geophysical Data. — Four kinds of 

 underway data are included in this category: 

 Underway Marine Bathymetry (MB), Underway 

 Marine Seismic Reflection (MSR), Underway Ma- 

 rine Magnetics (UMM), and Underway Marine 

 Gravity. 



• About 25 percent of the Underway Geophysi- 

 cal Data are taken in the EEZ. Data are in- 

 creasing in all sets. Except for MSR, most of 

 the data are in unaltered digital form stored 

 on magnetic tape. The MSR data are 45 per- 

 cent on paper, 40 percent on microfilm, and 

 15 percent on magnetic tape. While 85 per- 

 cent of the MSR data are analog, the MSR 

 digital archive alone totals about 3,000 reels 

 of low-density tape. The remaining 3 digital 

 sets total about 5 million records on 10 high- 

 density reels, about half of which are MB. 



• The average delay from sampling to report- 

 ing for all sets is about 5 years. All data are 

 made available upon request. 



• The combined rate of accumulation of data for 

 all sets is about 100 megabytes per year. 



• Future use for all sets is estimated to increase 

 at about 25 percent per year. 



Problems and Successes with Underway Data. 



— An internationally accepted format for underway 

 geophysical data is in general use. Flow of data to 

 NGDC has been good from the Minerals Manage- 

 ment Service, U.S. Geological Survey, Scripps In- 

 stitution of Oceanography, Hawaii Institute of Ge- 

 ophysics, Lamont-Doherty Geological Laboratory, 

 and the University of Texas at Austin. Other insti- 

 tutions' performances in submitting data have been 

 spotty because they have not practiced centralized 

 long-term data management. A considerable amount 

 of data from some institutions has been lost or dis- 

 persed in laboratories. 



The National Oceanographic Data Center 



The mission of the National Oceanographic Data 

 Center (NODC) is to acquire, archive, manage, 

 and make oceanographic data available to second- 

 ary users. NODC has served in this capacity since 



