2i^2 



Wind-driven and thermal currents are of minor importance to naviation, 

 search and rescue but play a major role in modification of layer depth through 

 large-scale mass convergence/divergence in the surface layers of the oceans. 

 In the eastern North Pacific, convergence/divergence considerations have 

 frequently been found to outweigh all other terms contributing to changes in 

 layer depth. 



Heat transfer is of primary interest to ASW operations in that surface 

 cooling causes convective mixing (resulting in a deepening of the mixed 

 layer and intensification of thermocline gradient) while surface heating 

 forms a shallow, transient surface thermocline (in the absence of mechanical 

 mixing through wave action) . 



All of the above processes of interaction either contribute to sea 

 "noise" or modify surface and subsurface temperature structure, and therefore 

 influence sound propagation in the oceans . An accurate analysis and/or fore- 

 cast of the state of the total environment as influenced by' sea-air interaction 

 is the key to successful naval operations in general and to the Anti- Submarine 

 Warfare Environmental Prediction System (ASWEPS) in particular. 



The following table summarizes the principal environmental inputs to 

 ASVTEPSj there are others, such as bottom effects, but those listed here are 

 the problem areas under attack at Monterey (see Table I). 



THE FNWF MASTER SCHEME FOR OCEANOGRAPHIC ANALYSIS AND PREDICTION 



Figure 1 outlines the master scheme developed at Monterey for numerical 

 analysis and prediction of oceanographic elements and processes (see FNWF 

 Tech. Memo No. 5)- If nothing else, the figure shows the complexity of the 

 numerical program being undertaken by FNWF in the general field of interest 

 to this conference. 



Looking first at the column headed Basic Data , one can see that a large 

 part of the input data to this program is derived from meteorological observa- 

 tions . Since the number of BT observations is insufficient for truly synoptic 

 oceanographic analyses (except perhaps in limited areas), we are forced to 

 derive the marximum information from meteorological reports at the ocean surface . 

 The basic approach at FNWF has been to obtain the first estimate of oceanic 

 thermal structure from purely exchange considerations and then to modify this 

 "guess" with BT data where available. 



The various computations involved in this method of oceanographic analysis 

 and prediction are summarized in the middle of Figure 1 under the column headed 

 Computed Quantitites and Processes . The flow diagramming leading to and result- 

 ing from these computations serves to emphasize the entire concept of sea/air 

 exchange utilized in the FNWF oceanographic scheme. Details of some of the 

 more important components of this overall plan will be covered herein or by 

 Dr . Laevastu . 



