Page 1

Pierre Pellerin and several collaborators

Recherche en Prévision Numérique (RPN)Meteorological Research Division, Science and Technology Branch

CAS Technical Conference Korea, November 2009

Development of the Canadian Coupled Atmosphere-Ice Ocean Forecast System

Page 2

1) Demonstration project: - Scientific results: Development of the Gulf St-Lawrence forecast system A first operational fully coupled Atmosphere-Ocean-Ice

2) R&D Strategy to Expand and Globalized the coupled system.

Plan:

Page 3

Development of the Gulf St-Lawrence forecast system A first operational fully coupled Atmosphere-Ocean-Ice

Gulf of St. Lawrence

N. Atlantic

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

Circulation is controlled : • by tides, • exchanges with atmosphere, • runoff from land,• the seasonal ice cover, • and the inflow through the bounding

straits

Page 4

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)

Methodology

Page 5

AtmosphereOcean-Ice

Each: 600 seconds

IR and Vis flux, Humidity, Pressure, Winds, Precipitation, Temperature.

Heat and Vapour Flux IR flux .

15 kmtimestep=600s

5 kmtimestep=300s

Coupler

CouplerCoupling description

Page 6

Ice fraction48h forecast2 way coupled

Atmosphere-Ocean-IceAn interesting Case

Case: Particularly interesting given that the intense atmosphericcirculation that dramatically changed the Ice conditionsin only 48 hours was preceded by a cold and relatively quiet period.

Page 7

C

d)

A

C

0

20

40

60

80

%

Anticosti

Clouds

Clouds

Ice

Water

Ice Observation Forecast (coupled) Ice

Valid: 14/03/97 20 Z after 44 hours

Atmosphere-Ocean-IceAn interesting Case Ice Forecast

Page 8

Atmosphere-Ocean-IceAn interesting Case

Difference Air temp.Coupled - Uncoupled

Impact on surface air temperature

Page 9

Impacts on low level clouds (air-ocean exchanges)

Uncoupled Fully coupleda) b)

c)

WaterIce

Clouds

AVHRR

Nov

a-S

coti

a

New-Brunswick

P-E. I.

Cape-Breton

M. I.

CloudsoverIce

Ice

WaterIce

Ice

Atmosphere-Ocean-IceAn interesting Case

Page 10

Data:

• Hourly air & dew point temperature, surface pressure, cloud cover

• 6-hourly precipitation accumulation

Objective Evaluation (Surface observations)

44 stations

Operational implementation

Page 11

Impact on atmospheric variables

Winter 2008

Forecast hour

% Coupled System better (> 50%)

Operational implementation

TemperatureHumidityCloudsPrecipitationSurface pressure

Page 12

Surface temperature (TT)

Forecast hour

Dew point temperature (TD)

Forecast hour

Statistics for February 2008

UncoupledFully coupled

Operational implementation

Page 13

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

Operational Coupled Atmosphere-Ocean-Ice system Gulf of St. Lawrence

Page 14

1) Demonstration project: - Scientific results: Development of the Gulf St-Lawrence forecast system A first operational fully coupled Atmosphere-Ocean-Ice

2) R&D Strategy to Expand and Globalized the coupled system.

Plan:

Page 15

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

Page 16

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

Global Coupled System

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

Page 17

Core Projects

Atmosphere

Ice-Ocean

Data Assimilation

Observations

Models

Atmospheric Forecasts

Products

Data Assimilation

Observations

Models

Project 1:Project 1: Atm-Ice-Ocean Coupling (models and data

assimilaton)

Project 2:Project 2: Ice-Model

Project 4:Project 4: Ice Data Assimilation

Ice-ocean Forecasts

Products

Project 3:Project 3: Ocean Data Assimilation and Ice-Ocean Forecasting

Global Coupled System

Project 1: Gulf St-Lawrence

Atm.-Ocean-IceShort termHigh-Resolution

Project 3: Great-Lakes

Atm.-Lakes-IceShort termHigh-Resolution

Project 2: ArcticAtm. – IceShort term forecastsHigh-Resolution

ORCA025

Project 4: Global

Page 1904/20/23 Page 19

Mont-Joli, 06 Feb. 2008

GEM Coupled Observations

Operational implementation

Fully Coupled system VS Operational GEM (48 hours forecast)

GEM Operational(Uncoupled)

~ 24 hours