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(Coupled) Arctic Regional Climate Model
Intercomparison Project (C)ARCMIPK.
Dethloff, A. Rinke, W. DornAlfred Wegener
Institute for Polar and Marine Research,Potsdam,
Germany (C)ARCMIP group
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• (Coupled) Arctic Regional Climate Model
  Intercomparison Project
• 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?)

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(C)ARCMIP

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

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(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

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ARCMIP1 simulations for the Beaufort Sea and
SHEBA period
ARCMIP1 group 1. AWI Dethloff, Rinke 2.
CIRES Cassano, Shaw, Serreze 3. DMI
Christensen 4. GIT Curry, Inoue, Liu 5.
Met.no Haugen, Køltzow 6. MPI Pfeifer,
Jacob 7. Rossby Centre Wyser, Jones, Döscher 8.
Uni. Melbourne Lynch 9. Uni. Quebec Girard,
Laprise, Du 10. Uni. StockholmTjernström, Zagar,
Svensson
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ARCMIP1 simulations for the Beaufort Sea and
SHEBA-period
Model grid 61x48 grid points 3500x2800 km2
Trajectory of ice camp during SHEBA year
SHEBA Surface Heat and Energy Budget of Arctic
Ocean Sept. 1997-Sept. 1998
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ARCMIP1 simulations for the Beaufort Sea and
SHEBA period

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

• Participating models
• ARCSyM (USA)
• COAMPS (S,USA)
• HIRHAM (D,DK)
• CRCM (C)
• RCA (S)
• HIRHAM.no (N)
• REMO (D)
• 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

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ARCMIP1 simulations for the Beaufort Sea and
SHEBA period
Across-model scatter 2m air temperature
across-model scatter (isolines) inter-model
stdev C significance of scatter (color) ratio
of intermodel stdev to observed variability
Rinke et al., 2006
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ARCMIP1 simulations for the Beaufort Sea and
SHEBA period
Surface radiation and clouds
Wyser et al., 2008
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ARCMIP1 simulations for the Beaufort Sea and
SHEBA period
Radiation-cloud relationship
SWD W/m2
Cloud cover
SWD W/m2
CWP g/m2
Wyser et al., 2008
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ARCMIP1 simulations for the Beaufort Sea and
SHEBA period
Scaled sensible heat flux vs. temperature
difference
Tjernström et al., 2005
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ARCMIP1 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

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ARCMIP1 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,
doi10.1007/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,
doi10.1007/s00382005-0095-3 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, doi10.1007/s10546-004-795
4-z
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(C)ARCMIP

• 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).

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ARCMIP2 simulations for the pan-Arctic and
IPY-years

• 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.

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ARCMIP2 simulations for the pan-Arctic and
IPY-years
Evolution of surface pressure at NP35 February
Trajectory of NP35 ice camp November 2007-March
2008
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(C)ARCMIP

• 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) HIRHAMNAOSIM (Dorn,
  Dethloff, Rinke, AWI)
• REMO-MPI/OM (Mikolajewicz, MPI) WRF-NPS
  (Cassano, Gutowski, Maslowski, US)

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CARCMIP simulations for the pan-Arctic

• 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.