Pierre Pellerin and several collaborators Recherche en Prévision Numérique (RPN)

1. Development of the Canadian Coupled Atmosphere-Ice Ocean Forecast System Pierre Pellerin and several collaborators Recherche en Prévision Numérique (RPN) Meteorological Research Division, Science and Technology Branch CAS Technical Conference Korea, November 2009

2. 1) Demonstration project:- Scientific results: Development of the Gulf St-Lawrence forecast systemA first operational fully coupled Atmosphere-Ocean-Ice2) R&D Strategy to Expand and Globalized the coupled system. Plan:

3. Circulation is controlled: • by tides, • exchanges with atmosphere, • runoff from land, • the seasonal ice cover, • and the inflow through the bounding straits The Gulf of St. Lawrence forecast system: • Initiated 13 years ago by the Maurice Lamontagne Institute (DFO) and Recherche en Prévision Numérique (EC) • Between January and March is nearly entirely cover of Ice • Ice conditions can change very rapidly • Coastal weather forecasts are very affected by the ocean conditions. • During the ice period, both systems are particularly interdependent. • To improve the atmospheric forecasts (icing, clouds, fog,…) • To improve the ocean-ice forecasts (ice, currents, temperature, waves…) • To improve the services: Major Seaway • Users: EC, coast-guard, DFO, maritime transportation, DND • Very interesting laboratory: Semi-enclosed Sea Development of the Gulf St-Lawrence forecast system A first operational fully coupled Atmosphere-Ocean-Ice Gulf of St. Lawrence N. Atlantic

4. Methodology Models & Coupling strategy • Atmosphere: Global Environmental Multi-scale (GEM): • Regional configuration LAM @ 15km - 2.5 km and 58 levels; • Ocean: Gulf of St. Lawrence Model (ROM, Saucier et al. 2003): • 3D Ocean @ 5km and 73 levels; version 4.9.5 (5.2.2); • Sea-ice (dynamic - thermodynamic); • Elastic-viscous-plastic (EVP) model (Hunke & Dukowicz, Los Alamos CICE model, 1997); • Thermodynamic: Semtner, 1976; • Coupler OASISv3-Gossip (Valcke 2004)

5. Coupling description Coupler Heat and Vapour Flux IR flux . Ocean-Ice Atmosphere Each: 600 seconds Coupler IR and Vis flux, Humidity, Pressure, Winds, Precipitation, Temperature. 15 km timestep=600s 5 km timestep=300s

6. Atmosphere-Ocean-Ice An interesting Case Ice fraction 48h forecast 2 way coupled Case: Particularly interesting given that the intense atmospheric circulation that dramatically changed the Ice conditions in only 48 hours was preceded by a cold and relatively quiet period.

7. Ice Observation Forecast (coupled) Ice C Clouds Water A Anticosti C % 80 60 Ice Clouds 40 20 0 d) Valid: 14/03/97 20 Z after 44 hours Atmosphere-Ocean-Ice An interesting Case Ice Forecast

8. Atmosphere-Ocean-Ice An interesting Case Impact on surface air temperature Difference Air temp. Coupled - Uncoupled

9. AVHRR New-Brunswick Ice Ice Ice Water Ice Water Nova-Scotia Clouds over Ice Clouds M. I. P-E. I. c) Cape-Breton Atmosphere-Ocean-Ice An interesting Case Impacts on low level clouds (air-ocean exchanges) a) b) Uncoupled Fully coupled

10. Operational implementation Objective Evaluation (Surface observations) • Data: • Hourly air & dew point temperature, surface pressure, cloud cover • 6-hourly precipitation accumulation 44 stations

11. Operational implementation Impact on atmospheric variables Winter 2008 % Coupled System better (> 50%) Temperature Humidity Clouds Precipitation Surface pressure Forecast hour

12. Operational implementation Statistics for February 2008 Surface temperature (TT) Dew point temperature (TD) Fully coupled Uncoupled Forecast hour Forecast hour

13. Operational Coupled Atmosphere-Ocean-Ice system Gulf of St. Lawrence Summary: • EC and DFO have successfully developed a fully-interactive coupled atmosphere-ice-ocean forecasting system for the Gulf of St. Lawrence (GSL) • This system will become fully operational at the Canadian Meteorological Centre (CMC) this winter • Results during the past year have demonstrated that the coupled system produces improved weather forecasts in and around the GSL during all seasons • Shows that atmosphere-ice-ocean interactions are indeed important even for short-term Canadian weather forecasts • Used by Canadian Ice services, Coast-Guard, Department National Defense

14. 1) Demonstration project: - Scientific results: Development of the Gulf St-Lawrence forecast system A first operational fully coupled Atmosphere-Ocean-Ice2) R&D Strategy to Expand and Globalized the coupled system. Plan:

15. Canada requires ocean forecasts and information services for: Weather prediction Sea ice prediction (e.g. CCG: seal hunt, navigation) Fisheries and aquaculture management Increased understanding of biological field observations Attribution and mitigation of regional climate change impacts Risk assessment for extreme events (sea level, waves, currents) Search and Rescue, dispersion of pollutants Global Coupled System 15

16. Global Coupled System Mercator-Canada Alliance Summary: • In 2005 Environment Canada, Department of Fisheries and Oceans and Department of National Defense recognized a common need for products and modeling capabilities that can be provided by an operational global coupled atmosphere-ocean-ice data assimilation and prediction system • MERCATOR was selected by an inter-departmental advisory panel to become partner for the development of an operational Canadian coupled atmosphere-ocean-ice data assimilation and modelling capability 4 years later: • A MOU between the three departments is now in place: Research, Development and Implementation of Operational Coupled Atmosphere-Ocean-Ice Assimilation and Prediction Systems for Canada • A letter of intent between Canada and Mercator put in place • Collaborations and Exchanges underway • The current operational ocean model of the Mercator-Ocean group has been installed in Canada and is now used as common research system between DFO-EC • An International Memorandum of Understanding (MOU) between Canada and the Mercator Océan is being drafted and is under review • Main objective: Build a medium-long term perspective of collaboration between the two groups

17. Global Coupled System Core Projects Observations Atmospheric Forecasts Data Assimilation Products Atmosphere Models Project 1:Atm-Ice-Ocean Coupling (models and data assimilaton) Models Data Assimilation Ice-ocean Forecasts Products Ice-Ocean Observations Project 2: Ice-Model Project 3:Ocean Data Assimilation and Ice-Ocean Forecasting Project 4:Ice Data Assimilation

18. Project 2: Arctic Atm. – Ice Short term forecasts High-Resolution Project 4: Global Project 1: Gulf St-Lawrence Project 3: Great-Lakes Atm.-Ocean-Ice Short term High-Resolution Atm.-Lakes-Ice Short term High-Resolution ORCA025

19. Operational implementation Fully Coupled system VS Operational GEM (48 hours forecast) Mont-Joli, 06 Feb. 2008 GEM Coupled Observations GEM Operational (Uncoupled) ~ 24 hours 11/9/2014 Page 19