GOVST meeting – 8-10 june 2009, Toulouse Mercator-Ocean : French contribution to GODAE OceanView...

GOVST meeting – 8-10 june 2009, Toulouse

Mercator-Ocean : French contribution to GODAE OceanViewannual report

Nicolas Ferry, [email protected] with the help from E. Dombrowsky, Y. Drillet, L. parent, M. Drevillon, G. Garric, CE Testut, B. Tranchant, JM Lellouche, E. Rémy, E. Greiner, S Buarque,

GOVST meeting, 8-10 june 2009

Outline

- System & services overview

- Progresses since GODAE final symposium

- In the near future…




- In the near future


Introduction (1/2)

Mercator Océan : Legal entity owned by CNES, CNRS, IRD, IFREMER, Météo-France and

SHOM Mercator Océan is an operational, global, real-time ocean forecast

service provider Its activity follows 3 main axes:

Exploit and maintain real-time numerical ocean forecast systems

Ensure service level as required by its users, and promotes the development of downstream services at the Global scale

Prepare service evolutions to maintain service quality close to the state of the art


System suite developed and operated North Atlantic + Med eddy resolving (routine) Global eddy permitting (routine) and low resolution (routine) Global eddy resolving (demo in April 2008)

Methodology defined, and tools implemented for assessment and validation GoDAE Metrics

Links with data centers developed CORIOLIS for the In Situ observing system SSALTO/DUACS for the altimetry Météo-France for the SST (to evolve within MyOcean) and Forcing

Connection with other operational oceanography centers established Within EU-GMES : MyOcean project started 1st April 2009

UKMO, NERSC, INGV, DMI, DFO… Bilateral collaborations

• MOON (Med sea), GOAPP (DFO/EC Canada), … International

• GoDAE, EuroGOOS, …

Introduction (2/2)


The model configurations

1 code : NEMO (OPA9+LIM)

1 grid : all the configurations are on the same ORCA (tripolar) grid

One single input dataset : initialization and forcing interpolated inline

Some of these configurations are shared with the scientific and operational community

ORCA025: Drakkar and GLORYS Project, Barnier et al.

UKMO, CMCC, ECMWF, DFO, …

ORCA025

1 point sur 12

ORCA12ATL12NEATL36


T , S

Ψ

U, V

Ugeo , Vgeo

Ubar , Vbar

+

Model initialisation

Baroclinic

Hbar

SAM2 kernel

Modal Space(Reduced Space)

Control SpaceSEEK

Analysis

T(k)

S(k)

Barotropic

U(k)

V(k)

The assimilation scheme: SAM2(Kalman Filter type)

3D modesacting on 3D space

SAM2v1: SEEK filter using multivariate 3D error modes


Several model configurations operated for several uses

Regional eddy resolving (2002) North Atlantic + Mediterranean operational: 5-7 km, OPA8, ROOI assimilation of alti. T/S and SST From April 2008: 1/12° (6.5 km at 45°N), NEMO/LIM, SEEK assim. of alti, T/S and SST, daily fcst Target: mesoscale upper ocean, downscaling to smaller regional and coastal regions, …

Global eddy permitting (09/2005 ) operational: ¼°, OPA8, ROOI assimilation of alti only From April 2008: ¼°, NEMO/LIM, SEEK assim. of alti, T/S and SST

• Has been operated in demo mode during Mersea TOP2: AprilSept 2007 Target: global ocean climate monitoring, biology, sea ice, reanalysis, …

Global low resolution (05/2004 ) Today: 2°, OPA8, SEEK assim of alti, T/S and SST Target: oceanic initial conditions for coupled seasonal prediction, reanalysis

Global eddy resolving (to be operational at the end of MyOcean) NEMO/LIM+SEEK 1/12°

• Has been demonstrated in April 2008 Target: Global Marine Core Service and downscaling to European regions

Northeastern Atlantic high resolution (to be operational at the end of MyOcean) NEMO 1/36° +SEEK + Tidal free surface Target: IBIROOS Marine Core Service Boundary data to coastal systems


System performance: SLAGlobal 1/4° (Left) versus Global 1/12° (Right)

Nov 07 Apr 08 Nov 07 Apr 08

~ =

+

+


Mercator 1/12° April 21 2008Mercator 1/4 April 21 2008OSTIA April 21 2008


SERVICES: Delineated eddies and frontsFrench Navy product based on Mercator

Front and eddies with potential acoustic impact detected by Navy forecasters and delivered to Navy headquarters for operations at sea


> 0 means degradation in %

0 is the baseline (3 sats)

< 0 means improvement in %

RMS(Obs-Expi)-RMS(Obs-Baseline)

RMS(Obs)

Shown here diags from innovation: Obs (not yet assimilated) - Forecast

Full domain

POMME region

Cape Verde region

Assim of: In situ T/S + RTG SST + •No alt•Jason•Jason + Envisat•Jason + Envisat + GFO (baseline)•Jason + Envisat + GFO + T/P•Progressive loss ( )

SERVICES: Observing systems impact studies:Impact of altimeter data coverage

Benkiran, 2008


SERVICES: Ocean Indicators


- System overview

- Present capacity and services


- Future plans


Progresses since GODAE final symposium

GLORYS-1V1 : 2002-2008 global ocean reanalysis at ¼° produced and available

- GLORYS : French initiative supported by GMMC (Mercator-Coriolis)- Involves French oceanography labs (LEGI, LPO, LOS, CNRM,LOCEAN) and Mercator + Coriolis- European level: MyOcean project, - International level: contribution to CLIVAR GSOP

- OBJECTIVE : obtain an eddy permitting (1/4°) realistic 4D description of the ocean history:


GLORYS-1

GLORYS-2

GLORYS-3

Stream1: 2002-2008“ARGO”

Stream2: 1993-2008“Altimetry”

Stream3: 1958-2008ERA-40

T/S prof.: 800<SST: 1°x1° or coarserSLA: NO DATA

T/S prof.: ~1000SST:1°x1° SLA: 12000~50000

T/S prof.: 2000~4500SST: 0,5°x0,5° 0,1°x0,1°SLA: ~75000

Obs. / 7 days

Time schedule:2008: Stream12009: Stream22010-11 Stream3

GLORYS: different Streams


Overview of GLORYS reanalysis system

Reanalysis system :

Based on the current global operational forecasting system + customization

- Use NEMO: ocean model with ORCA025 grid + LIM2_EVP sea-ice model

- Data assimilation engine : Based on SEEK filter (Pham et al., 1998)

- Incremental Analysis Update (IAU) approach continuous time solution

Assimilated Observations:

- Altimetry : along track SLA data SSALTO/DUACS (T/P, Envisat, GFO, Jason1)

- SST: NCEP RTG 0.5° product

- In situ T, S: CORA-02 Q.C. data base provided by CORIOLIS


Rms misfit ~ 8cm

Results: Nov 2001 - April 2008comparison with assimilated data

Rms misfit

Mean misfit

TE

MP

ER

AT

UR

E

Ob

s-F

cst

SL

A

Ob

s-F

cst

0

1°C


Example of SST patterns in the Gulf Stream region for 9th April 2008:

OSTIA SST: used in verification mode ODYSSEA SST

0.05° 0.1°

GLORYS SST

0.25°

RTG NCEP SST: assimilated data

0.5°

Reynolds ¼° AVHRR-AMSR OIv2


SLA Std. Dev.

Aviso Altimetry GLORYS1

2002 – 2007


GLORYS : Global Ocean Heat Budget

Global mean equivalent Heat Flux

W/m2

0

-12

20 HEAT CHANGE INDUCED BY DATA ASSIMILATION

TOTAL OCEAN HEAT CHANGE

SURFACE HEAT FLUX


SSH budget: baroclinic and barotropic contributions

baroclinic

barotropic

SSH


Water Mass budget: Global Mean SSH – dynamic heightEstimation based on GRACE data

Water Mass Budget

seasonal signal: ~15 mm amplitudemaximum in autumn

GRACE data GLORYS1V1

J. Famiglietti et al., 2008


Sea Ice

Sea ice extent monthly anomalies

Arctic

Correlation: 0.8

GLORYS with LIM2_EVP

CERSAT DATA



- Present capacity and services


- In the near Future


In the near future (1/2)

o MyOcean project has started (April 2009- April 2012) MyOcean will strongly drive Mercator activity next 3 years main challenge for Mercator (& other MyOcean oceanography centers) : improve the quality of operational systems, i.e:

- Keep as close as possible to the state-of-the-art in an operational context- Ensure continuity of service with strongly evolving systems- Meet users expectations in terms of product quality

o New operational systems are planned : - Global eddy resolving (1/12°) : demo mode in december 2009 - High resolution (1/36°) in the Iberian Biscay Irish region (IBIROOS) 2011

o Real Time: - Weekly assimilation and medium range forecast O(2 weeks) - Daily forecast cycle O(1 week) GLO1/4°+NATL1/12°


In the near future (2/2)

o Reanalysis activity: - GLORYS1V2 : Version 2 of Stream 1 (2002-2008) improved data assimilation engine (covariances, bias correction…) produced end 2009 - GLORYS: 15-year reanalysis (1993-2008) within MyOcean 2010

o R&D: - data assimilation of Ice drift / concentration - HR SST data assimilation

- Biogeochemical global analyses


Thank you

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GOVST meeting – 8-10 june 2009, Toulouse Mercator-Ocean : French contribution to GODAE OceanView...

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