1. Forecast system version
System name: GCFS 2.0
First operational forecast run: April 2018
2. Configuration of the forecast model
Is it a coupled model? Yes
Coupling frequency: 1 hour (Better use more specific question? Here or elsewhere?)
2.1 Atmosphere and land surface
Model | ECHAM 6.3.04 |
---|---|
Horizontal resolution and grid | T127 (~100 km) on regular Gaussian grid |
Atmosphere vertical resolution | L95 |
Top of atmosphere | 0.01 hPa |
Soil levels | 5 Level 1: 0 - 0.065 m Level 2: 0.065 - 0.319 m Level 3: 0.319 - 1.232 m Level 4: 1.232 - 4.134 m Level 5: 4.134 - 9.834 m |
Time step | 200 s |
Detailed documentation:
ECHAM6: Stevens et al., 2013
Soil scheme: Hagemann and Stacke, 2014
More model details? (e.g. land surface model?)
2.1 Ocean and cryosphere
Ocean model | MPIOM 1.6.3 |
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Horizontal resolution | TP04 (0.4°) on a tripolar grid |
Vertical resolution | L40 |
Time step | 1 h |
Sea ice model | Thermodynamic and sea-ice dynamics |
Sea ice model resolution | same as ocean model |
Sea ice model levels | zero-layer model |
Wave model | NA |
Wave model resolution | NA |
Detailed documentation:
MPIOM: Jungclaus et al., 2013
3. Initialization and initial condition (IC) perturbations
3.1 Atmosphere and land
Hindcast | Forecast | |
---|---|---|
Atmosphere initialization | ERA-Interim | IFS-Analyses |
Atmosphere IC perturbations | none | none |
Land Initialization | indirect via atmosphere initialization | indirect via atmosphere initialization |
Land IC perturbations | none | none |
Soil moisture initialization | indirect via atmosphere initialization | indirect via atmosphere initialization |
Snow initialization | indirect via atmosphere initialization | indirect via atmosphere initialization |
Unperturbed control forecast? | yes | yes |
Detailed documentation:
More DA details?
The assimilation for the atmosphere employs Newtonian relaxation of the reference data with the following variable dependend relaxation times:
- Divergence (48 hrs)
- Vorticity (6hrs)
- Temperature (24hrs)
- logarithm of surface pressure (24 hrs)
Data assimilation method for control analysis: same as for perturbed members
Horizontal and vertical resolution of perturbations:
Perturbations in +/- pairs:
3.2 Ocean and cryosphere
Hindcast | Forecast | |
---|---|---|
Ocean initialization | ORAS5 | ORAS5 |
Ocean IC perturbations | The very first hindcast ensemble in 1990 starts with lagged initialisation of the 30 members by each one day. Subsequently, bred vectors add small disturbances to the global three-dimensional ocean temperature and salinity fields | bred vectors add small disturbances to the global three-dimensional ocean temperature and salinity fields |
Unperturbed control forecast? | yes | yes |
Detailed documentation:
GCFS ocean data assimilation: Baehr & Piontek, 2014
More ocean data assimilation details?
Assimilation of sea-ice concentration ( coming from ORAS5) using Newtonian relaxation with ~20 days of relaxation time
Source and treatment of SST? (Other data sources - altimetry?)
4. Model uncertainties perturbations:
Model dynamics perturbations | no |
---|---|
Model physics perturbations | atmosphere: perturbation of diffusion in uppermost layer |
If there is a control forecast, is it perturbed? | unperturbed control forecast |
5. Forecast system and hindcasts
Forecast frequency | monthly |
---|---|
Forecast ensemble size | 50 |
Hindcast years | 1993 - 2017 |
Hindcast ensemble size | 30 |
On-the-fly or static hindcast set? | static |
6. Other relevant information
7. Where to find more information