Ocean Forecasting for Australia & New Zealand and Mesoscale Oceanography

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1 Ocean Forecasting for Australia & New Zealand and Mesoscale Oceanography Andreas Schiller 1 Graham Rickard 2 Gary Brassington 3 1 Centre for Australian Weather and Climate Research; Wealth from Oceans Research Flagship, CSIRO 2 National Institute of Water and Atmospheric Research 3 Centre for Australian Weather and Climate Research, BoM IMOS is supported by the Australian Government, through the National Collaborative Research Infrastructure Strategy and the Super Science Initiative

2 Three Related Presentations: (1) BLUElink - Australian activities (Schiller, Brassington) (2) Overview of NZ work (Rickard) (3) Circulation in the Tasman Sea (Brassington) - Existing Australia/NZ collaborations in ocean observing (and modelling) - Potential for building on/formalising existing collaborations - Potential for new collaborative activities/projects

3 Outline of Talk BLUElink Status: Global Forecasting & Reanalysis: OceanMAPSv2 & BRAN Coupled Modelling: CLAM Relocatable System: ROAM* Littoral zone forecasting system: LOMS Opportunities: Mesoscale oceanography The new global model: OFAM3 + BGC + SPINUP * Also see presentation by Gillibrand and Rickard about coastal operational modelling

4 Ocean Forecasting Australia Model: OFAM1&2 Global configuration of MOM4 Eddy-resolving around Australia 5-10 m vertical resolution to 200 m, then coarser Surface fluxes from NWP or ECMWF (reanalyses) Minimum resolution: ~100km ~10km resolution every 10 th grid point shown

5 Options Model (Incompressible, Boussinesq, Hydrostatic) OceanMAPSv2.0 OFAM2.0 (MOM4p1) No tides Grid resolution (90E-180E, 75S-20N) IO, SPO 5 m (0-10 m) 10 m ( m) Bathymetry Restoring DA (EnOI) Initialisation What is OceanMAPS? NOAA (GEBCO) and GA SSS (30 days) T/S >2000m (256 days) BODAS member static ensemble Adaptive nonlinear dynamical initialisation Options Fluxes In situ Quality control Remote sensing (Altimetry) Remote sensing (SST) OceanMAPSv2.0 ACCESS-G UM6.3, 3hrly (tau, SW, LW, Sens, Lat, P, E) GTS, USGODAE, Coriolis Duplicate checker CAWCR QC Jason1?, Jason2, Envisat?, AltiKa? AMSR-E, Navoceano L2P Brassington et al., 2012: Ocean Model, Analysis and Prediction System (OceanMAPS): version 2, CAWCR tech rep. under review. Sandery, P. A., G. B. Brassington and J. Freeman, 2010: Adaptive nonlinear dynamical initialization, J Geophys. Res., doi: /2010jc006260

6 OceanMAPS v1 OceanMAPS V2 RMSE SSHA Performance in the Australian Region CORR SSHA RMSE SST

7 Bluelink Reanalysis: Improvements RMS of observed altimetry signal RMS error obsmodel of 2008version RMS error obsmodel of 2010version

8 Coupled Limited Area Model (CLAM) CLAM is an ocean-atmosphere coupled model based on ACCESS NWP and OceanMAPS prediction systems at the BoM, incl. coupled data assimilation

9 CLAM-TC: Test Case TC Ului EXAMPLE: TC ULUI 3 Day forecast base date

10 Relocatable Ocean Atmosphere Model (ROAM) ROAM is a control system that allows a user to easily configure a model (ocean, waves, and/or atmosphere) User specifies region and resolution ROAM configures and runs model(s), puts input and output files on ftp site notifying the user of the run status and location of the files

11 Littoral Zone Forecasting Forecast wave (Height, Breaking, Direction) and current (U, V) conditions in the littoral zone involves: - High resolution grid : 5-20 m, domain size: 1-2 km - Depths < 20-30m, with local input - Relocatable: can handle wide range of shorelines, with local input - Perform forecasts in reasonable time, with hourly forcing from waves, tides, winds XBeach nearshore model developed at TU Delft and Deltares: wave module, circulation module and morphology module

12 BLUElink: Global and Nested Models OFAM1& CLAM 2km x 2km ROAM 2km 2km LOMS 10m x 10m

13 Mesoscale Oceanography: mean currents at mid-depth ( m) using a color wheel (Divakaran and Brassington) Domingues et al., 2007 Geostrophic surface currents derived from MDT BRAN2.1; represented using a color wheel for both direction and magnitude (m s-1), with bathymetry contours overlaid (500:500:3500 m)

14 Meridional structure of striations Annual mean current meridional section (averaged 90-95E) Depth ( m) averaged annual mean current Divakaran, P., and G. B. Brassington, 2010: Arterial ocean circulation of the Southeast Indian Ocean, Geophys. Res. Lett., doi: /2010gl Divakaran, P. (2011). Mesoscale circulation and variability of the Indian Ocean. PhD thesis, School of Earth Sciences, The University of Melbourne,

15 OFAM3 The new Bluelink model is called OFAM3 1/10 degree resolution between 75S and 75N 51 vertical levels with 5 m resolution near the surface Implicit tidal mixing increased mixing over water column, and higher bottom friction in regions of strong tides (e.g., NW Shelf of Australia and Indonesian Seas) Example of OFAM3 off Somalia

16 AVISO Altimetry vs. OFAM3

17 AVISO Altimetry vs. OFAM3

18 OFAM3 & Biogeochemistry

19 Andreas Schiller CSIRO Marine and Atmospheric Research, Hobart

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21 Operational Ocean Forecasting Real-time Observations Automatic Quality Control Data Assimilation Model Simulation Data Management Products and Services

22 Coupled Initialisation Heat flux & wind stress adjustments

23 Current systems Future systems Global systems: Current model space Near-term future model space > global eddy-res. systems regional systems littoral zone systems

24 Time varying striations 25 S-15 S = m/sec 5 S-15 S = 0.03 m/sec Equator-5 S = 0.1 m/sec Annual mean meridional velocity (averaged 90-95E) 60 day running average of the total velocity averaged between E and m depth from BRAN2.1, as a function of latitude and time.