Introduction

1. Introduction In the next few slides you will get an overview of the types of models that the Navy is using – analysis systems, tidal models and the primitive equation models. This brief introduction will be followed by an in-depth presentation on each set of models. The material for each model is presented in a consistent way. Each model will have a slide on each of the modeling issues we discussed in the numerical modeling portion of the course: domain, grid system, boundary conditions, data assimilation and implementation, plus a look at the output.

2. Operational vs Research Mode Operational: find the optimal configuration for goodsolutions everywhere. Research: findthe configuration forthebest solution for a given problem. Courtesy of Germana Peggion (USM)

3. Atmosphere Analysis Nesting/ Boundary Conditions Atm. Data Atm. Data Forecast Coupling Coupling Ocean Analysis Analysis Analysis Nesting/ Boundary Conditions Forecast Forecast Forecast Ocean Data Ocean Data OceanApplications IMAT, SAR, Dispersion Other MUSW TDAs OceanApplications IMAT, SAR, CB Dispersion SpecOp, AUV, MUSW TDAs NRL Ocean Dynamics & Prediction Coastal & Harbor (Fixed & Relo.) Global Courtesy of John Harding, NRL-SSC 2/10/01

4. Global to Littoral Nested Strategy NCOM 1/8 SST 8-27-2000 0000 GMT nowcast 5/15/00 SST Increasing Resolution Consistent Fields Courtesy of John Harding, NRL-SSC

5. Navy Ocean Circulation Prediction Expected Evolution FY 07-10 FY 04-06 FY 02-03 Naval Global Ocean Prediction HYCOM (Hybrid Coordinate Community Model) NLOM/NCOM 1.5 POP at FNMOC? NLOM/NCOM 1.X POP? SWAFS-Next based on SWAFS 1.0, NCOM 1.X & TOMS Community Effort) Navy Coastal Ocean Prediction SWAFS 1.0 ReloPOM ADCIRC SWAFS-Next II based on NCOM 1.X/ TOMS/HYCOM/ Finite Element/ Nearshore Wave Community Efforts) Navy Harbor Prediction Baroclinic FE ReloPOM &/or Commercial … ADCIRC ReloPOM &/or Commercial … Courtesy of John Harding, NRL-SSC

6. Essential elements of the Navy operational ocean circulation and tide models Adapted from Bill Burnett, CNMOC 9/24/01

7. Analysis Systems There are some software systems that the Navy uses to analyze, interpret, map and/or project data and derive estimated currents, which do not predict what the currents will be in the future. They sometimes refer to these as analysis systems, as opposed to models. These include OTIS, MODAS and MVOI.

8. Tide Models The Navy sometimes uses the term “tide models” to designate those numerical ocean models being run primarily for the purpose of predicting tidal heights and/or currents. At this time, the tide models used by the Navy are run in a 2D mode (no variation in the vertical dimension). By definition these models must include tidal forcing, but they may also include other types of forcing, just as other ocean circulation models used by the Navy may include tidal forcing.

9. Primitive equation models These are the most sophisticated type of ocean circulation model, including more of the physics than the analysis systems and shallow water equation models. While their increased complexity makes them applicable to a broader class of applications, and should result in more accurate solutions, it can also be more difficult to diagnose their behavior and to understand how various model choices affect the results.

10. “Mixed layer” models We will only consider mixed layer models applied to the upper part of the ocean, although you can also have mixed layers near the bottom of the ocean. Mixed layer models are 1D models that can help us understand how currents, temperature and density in the upper ocean evolve under the influence of wind forcing and heat exchange with the atmosphere. By themselves they do not include any effects due to coastal boundaries, tides, fronts etc.