(Coupled) Arctic Regional Climate Model Intercomparison Project

(C)ARCMIP

K. Dethloff, A. Rinke, W. Dorn

Alfred Wegener Institute for Polar and Marine Research,Potsdam, Germany

&

(C)ARCMIP group

(Coupled) Arctic Regional Climate Model Intercomparison Project

1) What processes are currently not accounted for (or not well) in Arctic

RCMs? What is the appropriate level of complexity of parameterizations?

What are the bias magnitudes ? What are the common model successes?

Are there common errors in the Arctic RCMs? recommendations for parameterization improvements

2) What is the level of uncertainty in current Arctic RCMs? quantify the scatter among the models

(in which variables and/or locations do show RCMs consensus, in which not?)

ARCMIP for the SHEBA sub-domain (successfully finished) ARCMIP for a Pan-Arctic integration domain (planned) CARCMIP for a Pan-Arctic integration domain (planned)

(C)ARCMIP

ARCMIP for the SHEBA sub-domain (successfully finished) 8 RCMs; 4 papers have been published Tjernström et al., 2005; Rinke et al., 2006; Inoue et al., 2006; Wyser et al., 2008

(C)ARCMIP

ARCMIP#1 group:

1. AWI: Dethloff, Rinke2. CIRES: Cassano, Shaw, Serreze3. DMI: Christensen4. GIT: Curry, Inoue, Liu5. Met.no: Haugen, Køltzow6. MPI: Pfeifer, Jacob7. Rossby Centre: Wyser, Jones, Döscher8. Uni. Melbourne: Lynch9. Uni. Quebec: Girard, Laprise, Du10. Uni. Stockholm:Tjernström, Zagar, Svensson

ARCMIP#1 simulations for the Beaufort Sea and SHEBA period

SHEBA: Surface Heat and Energy Budget of Arctic Ocean; Sept. 1997-Sept. 1998

Model grid:61x48 grid points~3500x2800 km2

Trajectory of ice campduring SHEBA year

ARCMIP#1 simulations for the Beaufort Sea and SHEBA-period

Participating models

1. ARCSyM (USA)2. COAMPS (S,USA)3. HIRHAM (D,DK)4. CRCM (C)5. RCA (S)6. HIRHAM.no (N)7. REMO (D)8. PolarMM5 (USA)

Experimental set-up Same domain Same horizontal resolution (50km) Same boundary conditions (lateral: ECMWF, lower: SSM/I, AVHRR) Different dynamics/physics, vertical resolution

Simulated period one year: SHEBA period September 1997-September 1998

ARCMIP#1 simulations for the Beaufort Sea and SHEBA period

Across-model scatter; 2m air temperature

winter summer

across-model scatter (isolines): inter-model stdev [˚C]significance of scatter (color): ratio of intermodel stdev to observed variability

Rinke et al., 2006

ARCMIP#1 simulations for the Beaufort Sea and SHEBA period

Wyser et al., 2008

Surface radiation and clouds

ARCMIP#1 simulations for the Beaufort Sea and SHEBA period

Wyser et al., 2008

Radiation-cloud relationship

SWD

[W/m

2 ]

Cloud cover

CWP [g/m2]

SWD

[W/m

2 ]ARCMIP#1 simulations for the Beaufort Sea and SHEBA period

shf ~ - CH U10m (T2m - Tsrfc) CH: heat transfer coefficient

Scaled sensible heat flux vs. temperature difference

Tjernström et al., 2005

ARCMIP#1 simulations for the Beaufort Sea and SHEBA period

Summary:

Simulated large-scale flow patterns reproduce observations and are in high agreement among the individual models.

Considerable scatter in temperature, radiation, clouds among different models even under strong constrain.

Largest scatter in 2m temperature over land and within the lowest 1000 m. Ensemble mean outperforms the individual models.

Significant biases for surface fluxes (connected with biases in clouds).

Key processes to improve: clouds, boundary layer-, land surface processes, coupling to the surface

ARCMIP#1 simulations for the Beaufort Sea and SHEBA period

References:

Wyser, K.; Jones, C.; Du, P.; Girard, E.; Willén, U.; Cassano, J.; Christensen, J.H.; Curry J.A.; Dethloff, K.;Haugen J.E.; Jacob, D.; Koltzow, M.; Laprise, R.; Lynch, A.; Pfeifer, S.; Rinke, A.; Serreze, M.; Shaw, M.J.; Tjernström, M.; Zagar, M., 2008: An Evaluation of Arctic Cloud and Radiation processes during the SHEBA year: Simulation results from 8 Arctic Regional Climate Models, Clim. Dyn. 30, 203-223, doi:10.1007/s00382-007-0286-1

Inoue, J., Liu, J., Pinto, J.O., Curry, J.A., 2006: Intercomparison of Arctic Regional Climate Models: Modeling Clouds and Radiation for SHEBA in May 1998, J. Clim. 19, 4167-4178

Rinke, A.; Dethloff, K.; Cassano, J.; Christensen, J.H.; Curry J.A.; Du, P.; Girard, E.; Haugen, J.E; Jacob, D.; Jones, C.G.; Koltzow, M.; Laprise, R.; Lynch, A.H.; Pfeifer, S.; Serreze, M.C.; Shaw, M.J.; Tjernström, M.; Wyser, K.; Zagar, M., 2006: Evaluation of an ensemble of Arctic regional climate models: spatiotemporal fields during the SHEBA year, Clim. Dyn. 26, 459-472, doi:10.1007/s00382–005-0095-3

Tjernström, M.; Zagar, M.; Svensson, G.; Cassano, J.; Pfeifer, S.; Rinke, A.; Wyser, K.; Dethloff, K.; Jones, C.

; Semmler, T.; Shaw, M., 2005: Modelling the Arctic boundary layer : An evaluation of six ARCMIP

regional-scale models using data from the SHEBA project, Boundary Layer Meteorol. 117, 337-381,

doi:10.1007/s10546-004-7954-z

ARCMIP#1 simulations for the Beaufort Sea and SHEBA period

ARCMIP for the SHEBA sub-domain (successfully finished)

ARCMIP for a Pan-Arctic integration domain (planned) at least 5 RCMs: HIRHAM (Rinke, Dethloff, AWI); COAMPS (Tjernström, MISU); RCA (Wyser, et al., SMHI); WRF (Cassano, Gutowski, US); CRCM (Laprise, et al., UQAM).

(C)ARCMIP

Simulation period: IPY-period 2007 – 2008

Experimental set-up:- pan-Arctic domain (different in each model)- same horizontal resolution (50 km)- same boundary conditions (initial and boundary: ECMWF; ice thickness from I-O model?) - ensemble runs

Observations: TARA, Oden, NP35, etc.

ARCMIP#2 simulations for the pan-Arctic and IPY-years

ARCMIP#2 simulations for the pan-Arctic and IPY-years

Trajectory of NP35 ice campNovember 2007-March 2008

Evolution of surface pressure at NP35; February

Observation HIRHAM Forecast12 HIRHAM Ensemble mean HIRHAM Ensemble members

ARCMIP for the SHEBA sub-domain (successfully finished)

ARCMIP for a Pan-Arctic integration domain (planned)

CARCMIP for a Pan-Arctic integration domain (planned) 4 RCMs: RCAO (Döscher, SMHI); HIRHAM–NAOSIM (Dorn, Dethloff, Rinke, AWI); REMO-MPI/OM (Mikolajewicz, MPI); WRF-NPS (Cassano, Gutowski, Maslowski, US)

(C)ARCMIP

Simulation period: ca. 1960-2008, and target: IPY-period 2007-2008

Experimental set-up:- pan-Arctic domain (different in each model)- similar horizontal resolution (atmosphere: 50 km, ice-ocean: 25 km)- same atmosphere lateral boundary conditions (ECMWF, NCEP) - ocean lateral boundaries climatological (Levitus, …)

Observations: - TARA, Oden, NP35, etc.- Low ice vs. high ice phases etc.

CARCMIP simulations for the pan-Arctic