Marine Modeling and Analysis Branch Ocean Waves

Global and Basin Scale Ocean Forecast Systems at NCEP/EMC Primary Users: NOAA: NWS, NOS, IOOS, OAR, JCSDA External: DHS, Academia, Japan (JAEA), GODAE OceanView  Eddy Resolving Ocean Modeling and Initialization  Coupled Modeling for Hurricanes (Air-Sea-Wave flux interaction, mixing)  Coupled Modeling for short-term, medium-term and seasonal scales (Air-Sea-Ice-Wave flux interactions, ensembles)  Coupled Ecosystem Forecasting (Biogeochemical, NPZD, tracers)  All Ocean Forecast Systems presently based on HYCOM, RTOFS (Real Time Ocean Forecast Systems) represents line of products Strong collaboration with US Navy, leveraging core HYCOM and data assimilation developments at NRL.

RTOFS-Global FY16 Upgrade Primary upgrades (developed by NRL as GOFS 3.1 ): 41 hybrid layers (increased from 32 layers) ― Air-Sea boundary flux improvements for coupled applications (including Hurricanes) ― Finer resolution for mixed layer (9 additional near surface layers) ― Improved vertical coastal resolution for downstream applications (NOS OFS, IOOS RA’s) Two-way coupled HYCOM with Los Alamos CICE (Community ICE code) (which replaces Energy-Loan Sea-Ice model) ― 1 hour coupling frequency ― Using ESMF v4.0 (non-NUOPC) ― Additional forecasts (ice thickness, ice concentration, ice drift and stress) Improved climatology/bathymetry

RTOFS Future Plans Global: —Deterministic, higher vertical resolution (up to 100 layers) —Coupling with GSM, Waves, Sea Ice via NEMS, BGC modules HYCOM-HWRF ― Operational in Atlantic, East Pacific, West Pacific and Indian ― Coupling with Waves via NEMS Basin Scale/Regional models: –RTOFS-Arctic, RTOFS-Atlantic, RTOFS-Pacific –Deterministic (at 1/24° or 1/36° degree), nested in Global. –Coupled within NEMS –Ensembles (at 1/12 degree, members), particularly for Arctic. S2A/S2S applications –¼ degree Global, 1/12 degree regional ensembles –Unified Data Assimilation (LETKF/Hybrid)

Ocean Data Assimilation Plans  Signed MOU with Navy to implement NCODA at NCEP for operational use.  Initially for RTOFS Global  3DVAR, seven overlapping regions  Configure to use NCEP data tanks and data streams.  Tentative implementation FY 2017/2018.  Add new observations in the future (e.g. SSS, HF Radar)  Extend to all RTOFS applications (3DVar and Hybrid)  LETKF with Univ. of Maryland for Unified DA applications

Operational Wave Model Suite System NameAcronymAreal CoverageHorz ResCycle Freq Fcst Length (hr) Global wave modelMulti_1Global4180 Global Hurricane wave modelMulti_2Global4126 Global wave ensemble modelGWESGlobal4240 Great Lakes modeling systemsGLW/GL WN Great Lakes2.5 kms4/484/147 Nearshore Wave Prediction System NWPSCoastal weather forecast office domains 1.8km - 50 m On dema nd 102 NOTE: No data assimilation in the wave models at the moment. A data assimilation system is currently under development. All models use restart files from previous cycle to initialize runs.

This past year Multi – 1 (Global waves) No upgrades Multi – 2 (Hurricane waves) Upgraded to run with a blend of HWRF / GFS forcing Model updated to new physics Improved response under hurricane conditions More accurate storm arrival times GLW / GLWN (Great Lakes) Upgraded to higher resolution curvilinear domain (2.5 km) Higher resolution wind forcing Better ice concentration

This past year (contd) GWES (Wave ensembles) Model updated to new physics Better response to high wind conditions and improved dissipation physics Matches the physics packages of Mullti-1 and Multi-2 Grid upgraded to ½ degree from 1 degree GEFS winds from 1 degree to ½ degree, and 6 hours to 3 hours NWPS (Nearshore wave system) New modeling system for coastal WFO domains Eastern and Southern regions scheduled to go into operations Jan 2016 (currently in final testing phase)

Over the next year Multi-1 – Expanding Arctic domain to the North Pole (from current 83 N) Multi-2 – Additional ¼ degree regional domains over Indian Ocean and Western Pacific (to account for HWRF driven winds in these regions) GLW / GLWN Adding Hourly NDFD driven short forecasts (48 hours) Dropping NAM driven cycles (will become part of ensemble system) Increasing nearshore resolution and improving physics Upgrade ice concentration intake (5 km to 1 km grid) GWES Replace legacy GEFS perturbed DA winds with Hybrid EnkF DA winds Expand the Arctic domain (like Multi-1) Reduce East Coast bias NWPS – Adding the Western, Alaska, and Hawaii domains

Near term (2 - 3 years ) Present Systems Increase nearshore resolution of Multi-1 (from current 7.5 kms to 2-3 kms) Move the Great Lakes model to an unstructured grid (for future coupling with circulation model) Aligning NWPS domains to meet NOS and WFO requirements (to aid coupling with NOS models) Transitioning select NWPS domains to higher resolution unstructured grids (based on need) A justification study for the Multi-2 system (see below) New Systems Development of regional GFE driven modeling systems for NHC and OPC An ensemble based Great Lakes wave system Development of a 3 way coupled (HWRF – HYCOM – WAVEWATCH III) hurricane modeling system In general, slowly transitioning the wave model suites to coupled systems.

Coupled Arctic System (NGGPS) Mesoscale coupled Atmosphere – Ocean – Ice (Waves, Land) Few days time range

Sea Ice Concentration Analysis Adding AMSR-2 sea ice in FY16 Added AVHRR-based filter in FY15

Sea Surface Temperature Analysis Adding GOES SST To add VIIRS, AMSR2, Himiwari, … New climatology New land-filling