Major characteristics of regional climate models used in NA-CORDEX
| CanRCM4 | CRCM5 (OURANOS) | CRCM5 (UQAM) | HIRHAM5 | RCA4 | RegCM4 | WRF | |
|---|---|---|---|---|---|---|---|
| Dynamics | Semi-Lagrangian Hydrostatic | Semi-Lagrangian Hydrostatic | Semi-Lagrangian Hydrostatic | HIRLAM Semi-Lagrange Hydrostatic | Semi-Lagrangian | Hydrostatic | Non-hydrostatic, Compressible |
| Land Surface Model | CLASS2.7 | CLASS3.5+ | CLASS3.5+ | ECHAM5 | RCA LSS | BATS | NOAH |
| LSM Input Databases | GLC2000 | USGS vegetation & lake fraction; ECOCLIMAP sand & clay; Webb et al. 1993 depth to bedrock; Kourzeneva lake depth; lake fractions adjusted to represent reservoirs and lakes and to better define Great Lakes | USGS vegetation & lake fraction; ECOCLIMAP sand & clay; Webb et al. 1993 depth to bedrock; Kourzeneva lake depth | Fixed seasonally varying LAI | ECOCLIMAP | USGS Global Land Cover Character-ization | USGS 24-category data |
| Driving Ocean BC Variables (ts/tos, sea ice) |
SSTs, sea-ice thickness, sea-ice fraction | SST, SIC | SST, SIC | SST, SICE | SST, sea ice | tos |
GFDL: tos, sic; |
| Sea Ice Character-istics | thickness and fraction | simple thermodynamic | simple thermodynamic | prescribed | two-layer temperature, constant thickness | inferred from tos | GFDL & MPI: sea ice provided as LBC; HADGEM: sea ice threshold set to 272.0 K (sea ice present at threshold); fractional sea ice used if sic available as LBC |
| Lake Model Character-istics | prescribed from driver | FLake | FLake | No lake model; interpolate lapse-rate corrected SST for lakes > 0.5 gridbox | FLake | Hostetler et al. (1993) lake model | Default WRF interpolation from nearby ocean SSTs |
| Sub-Grid Lakes | no | yes | yes | no | yes | no | no |
| Thermal / Water Layers | N/A | 17 to 15m soil depth, +1 for snow / soil to depth of bedrock, +1 for snow | 26 to 60m | 5 / 1 (+snow) | 5 / 3 | 3 / 3, 1 for snow | N/A |
| Vegetation Types | 4 | 4 (plus urban and bare soil) | 4 (plus urban and bare soil) | 75 classes | 12 generic PFTs | 20 surface types, 12 soil types | 24 types |
| Boundary Layer Parameter-ization | Bulk Richardson Formulation | Delage 1997 | Delage 1997 | ECHAM5 | TKE scheme with diagnostic mixing length and moist processes | Holtslag (1990) | MYJ |
| Explicit Moist Physics | Prognostic cloud liquid water and ice, statistical cloud scheme, interactive with aerosols | Sundqvist | Sundqvist | Prognostic liquid water and ice | Prognostic equation for total cloud water mixing ratio, diagnostic cloud fraction based on threshold relative humidity | SUBEX scheme, Pal et al (2000) | WSM3 |
| Cumulus Parameter-ization | Mass flux scheme for shallow and deep convection | Kain and Fritsch | Kain and Fritsch | Tiedke, Nordeng | Modified Kain-Fritsch | Grell scheme with Fritsch-Chappell type closure over land, Emanuel scheme over oceans | Kain-Fritsch (cu_physics=1) |
| Vertical Coordinate | Hybrid sigma-pressure | 58 hybrid levels, top at 10 hPa | 58 hybrid levels, top at 10 hPa | Hybrid, 31 levels | Hybrid sigma-pressure, 40 levels | Sigma, 18 levels | Terrain-following hydrostatic pressure coordinate, 28 levels |
| Spectral Nudging | Yes | Yes | No | No | No | No | Yes |
| Lateral Boundary Treatment | cos^2 relaxation with 1h-24h time scale | 10 semi-lag departure points | 10 semi-lag departure points | Tanh functional form of weights | 8 point Davies cosine-based relaxation | nudging with exponential weights | linear relaxation |
| Original Grid Size |
200 x 180 (0.44°) 380 x 340 (0.22°) |
212 x 200 (0.44°) 380 x 340 (0.22°) |
212 x 200 (0.44°) 380 x 360 (0.22°) 695 x 680 (0.11°) |
182 x 152 | 186 x 150 | 189 x 161 (50-km) 381 x 325 (25-km) |
159 x 151 (50-km) 318 x 302 (25-km) |
| Sponge Zone Depth |
4.4 degrees (all resolutions) | 10-point Davies blending | 10-point Davies blending | 10 points | 10 points | 12 points (50-km) 24 points (25-km) |
5 points (50-km) 10 points (25-km) |
| Spin-up Period | 1 year | None | ERA-driven simulations start 1958 | 1 year | 1 year | 1 year for ERA-driven simulations | 1 to 2.5 years depending on simulation |
| Length of Timestep | 1200s (0.44°) 600s (0.22°) |
1200s (0.44°) 600s (0.22°) |
1200s (0.44°) 600s (0.22°) 300s (0.11°) |
600 seconds | 1200 seconds | 100s (50-km) 50s (25-km) |
300s (50-km) 150s (25-km) |
| tasmin / tasmax Calculation | timestep | timestep | timestep | timestep | timestep | land surface timestep | 3-hourly |
| Longwave Radiation Scheme | Correlated-k distribution and McICA for clouds | Li and Barker correlated-k radiation | Li and Barker correlated-k radiation | Morcrette (1984) | Sass et al. (1994) | Kiehl et al (1996) | RRTM |
| Shortwave Radiation Scheme |
Correlated-k distribution and McICA for clouds | Li and Barker correlated-k radiation | Li and Barker correlated-k radiation | Fouquart and Bonnel (1980) | Sass et al. (1994) | Kiehl et al (1996) | Goddard (ra_sw_physics=2) |
| Uniform Aerosols | prognostic bulk aerosols | ozone | ozone | yes | yes | no | ozone+trace gases, no aerosols |
| Modeler | J. Scinocca | S. Biner | K. Winger | F. Boberg O. Christensen |
G. Nikulin | R. Arritt M. Bukovsky |
M. Bukovsky C. Castro H-I Chang |
| Institution | CCCma | Ouranos | UQAM | DMI | SMHI | Iowa State NCAR |
NCAR U Arizona |
| Reference | Scinocca et al (2015), J. Clim. 29, p.17 | Zadra et al., 2008; Martynov et al. 2013; Šeparović et al. 2013 | Zadra et al., 2008; Martynov et al. 2013; Šeparović et al. 2013 | DMI report 06-17 | Samuelsson et al. (2011), Tellus A 63.1; SMHI-RCA4 setup description | Giorgi et al (2012) Climate Research | Skamarock et al (2008) NCAR Tech Note |