Update on Coupled Air-Sea-Ice Modelling

Transcription

1 Update on Coupled Air-Sea-Ice Modelling H. Ritchie 1,4, G. Smith 1, J.-M. Belanger 1, J-F Lemieux 1, C. Beaudoin 1, P. Pellerin 1, M. Buehner 1, A. Caya 1, L. Fillion 1, F. Roy 2, F. Dupont 2, M. Faucher 2, T. Carrieres 3, S. Desjardins 4, Y. Lu 5, F. Davidson 6, D. Lefaivre 7,., J. Chanut and G. Garric 8 1 Meteorological Research Division, Environment Canada 2 Centre Météorologique Canadien, Environment Canada 3 Canadian Ice Service, Environment Canada 4 National Laboratory for Marine and Coastal Meteorology, Environment Canada 5 Bedford Institute of Oceanography, Fisheries and Oceans Canada 6 Northwest Atlantic Fisheries Centre, Fisheries and Oceans Canada 7 Institut Maurice-Lamontagne, Fisheries and Oceans Canada 8 Mercator-Océan, Toulouse, France GOVST SMRCP-TT, Rio de Janeiro, 5 November, 2012

2 Outline CONCEPTS connection NEMO Ice-Ocean Modelling Regional systems update Global systems update Summary Page 2 November-14-12

3 CONCEPTS Several new coupled systems under development as part of CONCEPTS Canadian Operational Network of Coupled Environmental Prediction Systems Tri-departmental collaboration To develop coupled atmosphere-ice-ocean forecasting systems Model development Coupling the GEM (Global Environmental Multi-scale) atmospheric model to NEMO (Nucleus for European Modelling of the Ocean) Collaboration with Mercator French operational oceanographic group CONCEPTS Page 3 November-14-12

4 General goal of CONCEPTS Altimeter Ocean modelling & Data Assimilation ARGO Coupled Global NEMO/GEM November 14,

5 Ice-ocean modelling using NEMO Global 1/4 resolution Medium range forecasting 1/4 Global Global 1 resolution Monthly-to-seasonal forecasting 1 Global N. Atlantic and Arctic 1/12 Short-to-medium regional forecasting Great lakes 2km Short term forecasting 1/12 N. Atlantic and Arctic Page 5 November-14-12

6 Coupled Atmosphere-Ice-Ocean Forecast System for the Gulf of St. Lawrence Initiated 14 years ago by the Maurice Lamontagne Institute (IML-DFO) and Recherche en Prévision Numérique (EC) EC and DFO have successfully developed a fullyinteractive coupled atmosphere-ice-ocean forecasting system for the Gulf of St. Lawrence (GSL). This system has been running operationally at the Canadian Meteorological Centre (CMC) since June Sensitivity studies during the past year have shown that the treatment of snow over ice in GEM has a strong impact on the mean errors of the uncoupled and coupled (no snow cover) systems for the month of February Improved treatments of snow in GEM are under development. NEMO is replacing the IML model and case studies are in progress. Page 6 November-14-12

7 STDE Statistics for February 2008 CPL-GL CPL NC1 CTRL1 CTRL

8 GEM-NEMO coupled in the Gulf of St. Lawrence Case study of an upwelling event SST analysis 48h SST forecast (GEM-NEMO) Strong westerly winds Coastal upwellings 48h change in SST -W (vertical velocity) (0-30m)

9 Impact of adding a dynamic SST in the weather forecast instead of keeping it constant Averaged latent heat flux difference (0-48 h) Air temperature 48 h forecast Air temperature difference at 48 h

10 EC s involvement in METAREA s Development of an integrated marine Arctic prediction system in support of METAREA monitoring and warnings. Development of short-term marine forecast system using a regional high resolution coupled multi-component modelling (atmosphere, land, snow, ice, ocean, wave) and data assimilation system To predict: - Near Surface atmospheric conditions, - Sea ice (concentration, pressure, drift, ice edge) - Freezing spray, - Waves, and - Ocean conditions (temperature and currents) Improved Arctic monitoring

11 CIS/MRD Sea-ice Analysis System (3Dvar FGAT persistence first guess) SSM/I CIS Chart M. Buehner, T. Carrieres, L. Pogson, A. Caya, RadarSAT North American Analysis: Four analyses per day of ice concentration at 5 km resolution Global Analysis: two analyses per day on 10km grid Currently assimilates: SSM/I, CIS daily charts, Radarsat image analyses Operational since March 2011 Work in progress to add: SSMIS, scatterometer, visibleinfrared, SAR and ice thickness satellite-based observations Page 11 November-14-12

12 N. Atlantic/Arctic Coupled Forecasting System Build on CNOOFS and Coupled GSL Develop coupled forecasting system for N. America/Arctic (METAREAS) Couple NEMO to GEM regional (10km) 5km LAM over METAREAS 17&18 with 5km Atm 4DVAR/EnKF 1/12 th regional SAM2 Produce 48hr weather and marine forecasts C-NOOFS 1/12 GEM RDPS 10km Page 12 November-14-12

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14 Horizontal Grids for the GEM Regional Deterministic Prediction System (RDPS) GEM-10-km grid (996x1028) 5 min timestep 4D-Var TL/AD 100-km grid

15 Regional System Version on IBM Power-7 Parallel tests at CMC: Summer 2012 Operational implementation occurred October 3 rd Key Features: 4D-Var-100km (replacing 3D-Var-100km) GEM-10km (replacing GEM-15km) Specifics: From 9 to 24 Time-slots for Assimilation Window (45 min 15 min binning; increase in the amount of Satellite & aircraft data assimilated) Global driver GEM-33km (replacing GEM-55km) Improvements to GEM-Physics (e.g. New climatology for ice thickness, Reduced fluxes over the ocean, Hysteresis effect in vertical diffusion as proposed by McTaggart-Cowan/Zadra)

16 METAREA Regional Ice Prediction System (RIPS) 4-48hr forecasts per day: -CICEv4.1 forced by CMC RDPS -5km North American grid Initialized with 3DVar ice concentration Analysis (00Z, 06Z, 12Z and 18Z). Also initialized with -CMC operational SST analysis -Glorys1v1 thickness climatology -Glorys1v1 MLD climatology -Glorys1v1 ocean current climatology

17 RIPS validation against 3Dvar analyses (whole domain) June 2010

18 RIPS validation against 3Dvar analyses (sub-domain) Bering Sea June 2010

19 RIPS Conclusions RIPS is in experimental mode (4-48h forecasts / day). Outputs are available since July 27 th. Objective tuning of RIPS against drifting buoys. RIPS beats persistence all year except in March. Currently working on improving thermodynamics. RIPS will be delivered to operations in winter 2012.

20 CONCEPTS Global Ice-ocean forecasting system Medium-range Coupled Global Prediction System Aims: Improve 10day deterministic weather forecasts Backbone for other CONCEPTS systems Boundary conditions for regional system, wave model Global conditions available for emergency response (e.g. DND) Description: Based on Mercator operation system (ORCA025 with SAM2) Also constrained with CIS/MRD 3DVAR ice analysis Coupled to 33km (25km) GEM global Status: Routine production of weekly ice-ocean analyses since Dec to implement operationally by March 2013 Evaluation of ice-ocean forecasts underway (results comparable to RIPS to 48- hours, always beats persistence beyond) Starting initial evaluation of coupled runs Mercator monitoring system being installed Page 20 November-14-12

21 CONCEPTS Global Ice-ocean forecasting system Monthly/seasonal Coupled Global Prediction System Aims: Improve monthly ensemble forecasts by adding coupled ice-ocean Develop configuration for GEM-NEMO seasonal forecasting system Description: Based on 1deg global NEMO (ORCA1) Initialize with SAM2+3DVAR analysis Coupled to GEM global ensemble system Status: Basic low-resolution GEM-ORCA1 configuration working Will begin initial evaluation of coupled runs shortly Page 21 November-14-12

22 High Resolution Deterministic Prediction System at Environment Canada GEM (Global Environmental Multiscale) model, limited area model (LAM) configuration; 1 LAM grid, x = 2.5 km; hour predictions, 2-4 runs per day; Full data assimilation system of atmospheric measurements; Land data assimilation system (250 m) for detailed initial conditions of surface fields; Associated ensemble prediction system to provide forecast uncertainties. By 2015, Environment Canada will have complete coverage over Canada by an unprecedented convection permitting and nonhydrostatic high-resolution numerical weather prediction system 14 November

23 Summary & conclusion Early systems have matured and are being implemented operationally. Regional systems are converging on a coupled GEM- NEMO framework for application in a variety of Canadian regions, with the Arctic as a major focus. An initial global ice-ocean forecast system has been developed and evaluated. A coupling-ready global ice-ocean data assimilation and forecast system has been developed and preliminary assessments of ice-ocean forecasts and coupled GEM- NEMO forecasts are underway. We look forward to continuing complementary, mutually beneficial international collaborations and exchanges.