INTRODUCTION 



As peirt of the United States' contribution to the International 

 Indian Ocean Expedition, the processing facilities of the National 

 Oceanographic Data Center (NODC) are made available to the Expedition 

 so that the observed data and the interpolated and computed values 

 may be furnished for publication at the earliest possible date. The 

 processing and computing techniq.ues currently used by NODC are geared 

 to a set of standardized observational units and codes. In order to 

 process these data efficiently for the oceanographic community, it 

 is desirable that they be reported in the units or codes which are 

 presently used and programmed for the NODC computers. Submission of 

 data on the NODC Physical and Chemical Data Form for Oceanographic 

 Stations, form NODC-EXP 316t/12 (2-62), and conversion to proper 

 standard units or codes (described in a special tri-llngual table 

 of units) vlll avoid time consuming delays during processing. (See 

 Appendix I, page 105, for sample Physical and Chemical Data Form.) 

 If the data from a peirticular cruise or group of stations can be 

 supplied in this standard form, the processing to the publication 

 listing stage can usually be completed in about three months . The 

 publication listing -will contain, in addition to the original obser- 

 vations, the following data: Interpolated temperature, salinity, 

 sigma-t, oxygen, and sound velocity values at standard depths, and 

 computed values of sigma-t, sound velocity, specific voliome anomaly, 

 and dynamic depth anomaly. Most of these computations are based on 

 formulas published in "The Oceans, Their Physics, Chemistry, and General 

 Biology" by Sverdrup, Fleming, and Johnson. 



During the processing of historical data by NODC, a great variety 

 of observational units was encountered; tables were required to convert 

 these units to a series of standard \inits or codes. These tables have 

 been reproduced as a publication for the sole use of the International 

 Indian Ocean Expedition participants. 



