NEAR-SURFACE  OCEAN  THERMAL STRUCTURE (NOTS) LEARNING   OBJECTIVES Identify applications, limitations, and assumptions of the  NOTS  program.  Interpret  NOTS  program outputs. The NOTS program is used to forecast changes in the upper ocean thermal structure due to mixing by surface winds, heating and cooling by surface heat, precipitation,  and  evaporation.  Program  output  consists of  profiles  of  temperature  with  respect  to  depth  at operator-specified  forecast  intervals;  forecast  profiles may be run through the SSP program and then routed to the OEF for use in various oceanographic and acoustic programs. APPLICATION The  NOTS  program  uses  initial  temperature profiles  and  observed  or  forecasted  surface meteorological data to predict changes in the upper ocean  thermal  structure  with  respect  to  time.  The forecast NOTS temperature profiles can be input to SSP and  then  used  by  the  RAY,  PPL,  and  Sensor Performance  Prediction  (SPP)  programs  to  predict acoustic   propagation   conditions   and   to   predict environmental  effects  on  fleet  ASW  sensors  and operations. LIMITATIONS AND ASSUMPTIONS The restrictions as well as the principles taken for granted in using the NOTS program areas follows: . This program operates under the assumption that oceanic  conditions  are  horizontally  homogeneous. (Horizontal  changes  in  the  ocean  thermal  structure  are not considered.) This program should not be used in the vicinity of strong currents, ocean fronts, or eddies. l Since the quality of meteorological forecasts can degrade  significantly  with  respect  to  time,  NOTS forecasts more than 24 hours long should be used with caution. . The operator should use caution when specifying cloud cover and precipitation rate information for a given forecast time. The program linearly interpolates these  values  for  model  forecast  times  between  the meteorological  forecast  times. l This program should not be used for locations over the continental shelf; neither should it be used near regions of significant river runoff. FUNCTIONAL DESCRIPTION The NOTS model is used to forecast changes in the upper  ocean  density  structure  due  to  mixing  by  surface winds, heating and cooling by surface heat fluxes, and evaporation  and  precipitation.  Input  to  the  model consists of date, time, and position information; initial temperature and salinity profiles; turbidity information; and   forecasts   (or   observations)   of   surface meteorological conditions such as wind speed, wind direction,  air  temperature,  humidity,  atmospheric pressure, cloud cover, and precipitation rate. The date, time, and position information, as well as the initial temperature  salinity  profiles,  are  retrieved  for  the operator-selected data set in the OEF. The surface meteorological data are entered by the operator by way of   the   keyboard. Optical   water-type   (turbidity) information for location of interest is retrieved from the permanent  data  base  (PDB)  file. Performing  an  upper  ocean  thermal  structure forecast involves three processing steps: 1. Initializing the model 2.  Calculating  surface  fluxes 3. Using the model to calculate the effects Output from the NOTS program consists of forecast profiles  of  temperature  with  respect  to  depth  for operator-selected forecast times. These profiles are routed to the NOTS forecast file. Operator-selected forecast profiles are displayed, both in tabular and graphical  formats. Output  from  this  program  is classified  and  should  be  labeled  as  required. SOUND SPEED PROFILE (SSP) GENERATOR  MODULE LEARNING   OBJECTIVES: Identify applications,  limitations,  and  assumptions  of the  SSP  program. Interpret  SSP  module outputs. The SSP generator module computes a sound speed profile  by  applying  Wilson’s  equation  for  ocean  sound speed  to  a  merged  depth/temperature/salinity  profile. This creates a sound speed profile that represents local 8-8