All of the services discussed are provided on a global basis. 

 Other meteorological services are provided as requirements of the 

 operating forces dictate. 



Let us move now to oceanographic services and products. 



Our approach is to treat the oceans and atmosphere as two fluids 

 in a single, coupled system with significant transfers of mass and 

 energy across the interface. It follows that we deal mainly with 

 physical oceanography — temperature, sound velocity, motion, and other 

 characteristics of the ocean which can change the operating environ- 

 ment. Our mission is to forecast these changes before they occur. 

 Since most of the driving forces are atmospheric in origin, it is 

 possible to predict changes in such ocean state variables as temper- 

 ature, sea state, and currents by integrating the total exchange of 

 heat and momentum occurring at the interface. 



The operational programs which comprise most of our oceanographic 

 services and which include the interface exchange concepts just de- 

 scribed, are : 



Sea surface temperature 



Sea state 



Layer depth products 



Currents (stream and transport) 



Sub -surface temperature structiire 



Underwater sound mapping 



Sonic range predictions 



Our synoptic analysis of all these products is limited by lack 

 of data; only sea surface temperature analysis can be prepared 

 synoptically, where "synoptic" means using today's data to prepare 

 today's analysis. In Figure l8 we see the coverage of sea surface 

 temperatxire reports. Contrast this with the bathythermograph report 

 coverage in Figure 19 . Obviously, the models used for oceanographic 

 forecasting, other than SST, must rely upon composite data sets and 

 accurate analysis of the atmospheric driving forces. 



To illustrate the method by which we treat the oceans and air 

 as a coupled system, I shall describe the analysis method used for 

 sea surface temperature (Fig. 20). Forecasting is based upon physi- 

 cal cause and effect principles. The forecast driving forces are 

 taken from numerical meteorological forecasts. Heat advection is 

 computed from sea surface temperature gradients and forecast sur- 

 face current components. Heating or cooling is computed from the 

 heat exchange forecast, utilizing wave mixing as one input. Forced 

 mixing by wave action is computed from wave forecasts. Forecasting 

 accuracy depends largely on the accuracy of the initial analysis and 

 the accuracy of the meteorological forecast. 



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