Three major problem areas, not all concerned with instrumentation 

 alone, exist: (1) surface temperature observations from fleet and 

 commercial ships, (2) bathythermograph data from fleet and other 

 vessels, and (3) temperature- depth measurements from survey and 

 research ships. 



It appears that improvements in the accuracy of surface tempera- 

 tures collected by commercial and fleet ships will have to be achieved 

 through better instructions and more careful screening of incoming 

 data. However, these can never be regarded as sources of precise 

 data. Development of an inexpensive recording thermometer (along the 

 lines of the thermitow, but hull-mounted) for installation on such ships 

 would greatly improve the potential for accurate temperature data 

 from these sources. If this potential is to be fully exploited, such 

 installations will have to accompanied by a program of instruction and 

 continuing review. 



Steps have been and are being taken to improve the quality of bathy- 

 thermograms through the issuance of better instructions, development 

 of better bucket thermometers, more frequent calibration of instru- 

 ments, improved slide blanks, and better screening and processing 

 techniques. However, it is the conclusion of this Committee that the 

 most marked advances can be made in the collection of accurate 

 temperature data at the present time by careful production engineer- 

 ing and development of one of the several electronic bathythermographs. 

 The first objective of such development would be to make available, 

 through normal channels, a standard, easily maintained, shallow-water 

 instrument. Once perfected, such an instrument could be modified for 

 deeper work and combined with manually triggered sample bottles for 

 making complete oceanographic stations. A longer range objective is 

 to make such an instrument sufficiently reliable and rugged that it 

 could replace the BT for fleet use. 



Although several versions of an electronic bathythermograph have 

 been tested and evaluated by the Hydrographic Office, none has 

 proven satisfactory for survey operations. However, each develop- 

 ment provided certain valuable characteristics. It is, therefore, recom- 

 mended that the laboratory and field testing of these instruments 

 continue and that steps be taken to find an organization able and willing 

 to further engineer, package, and fabricate several instruments made 

 up of the best features of the earlier developments. 



It is also recommended that the Instrumentation Division of this 

 Office select one of the simpler designs of temperature sensors, 

 preferably a thermistor-type, for fabrication in limited numbers for 



1-7 



