1. Forecast system version
Identifier code: CFSv2
First operational forecast run: 15 March 2011
2. Configuration of the forecast model
Is the model coupled to an ocean model? Yes
Coupling frequency: One hour (between atmosphere and open water)
2.1 Atmosphere and land surface
| Model | NCEP Global Forecast System |
|---|---|
| Horizontal resolution and grid | T128 (~ 1x1 Deg Lat/Lon) |
| Atmosphere vertical resolution | 64 Levels (sigma-pressure hybrid coordinates) |
| Top of atmosphere | 0.02 hPa |
| Soil levels (layers) | 4 Layer 1: 0-10 cm |
| Time step | 10 minutes |
Detailed documentation:
2.2 Ocean and cryosphere
| Ocean model | GFDL MOM4 |
|---|---|
| Horizontal resolution | Spatial resolution in the zonal direction of 0.5° and in the meridional direction, 0.25° from 10°S to 10°N, progressively decreasing to 0.5° from 10° to 30°, and is fixed at 0.5° beyond 30° in both hemispheres. |
| Vertical resolution | 40 Layers |
| Time step | 1 hour |
| Sea ice model | GFDL Sea Ice Simulator (part of GFDL MOM4 ocean model) |
| Sea ice model resolution | Sea ice model is on a tripolar grid; Resolution in polar regions is about 50x50 Km |
| Sea ice model levels | Three; one snow layer, and two equal-thickness ice layers. |
| Wave model | Not Applicable |
| Wave model resolution | Not Applicable |
Detailed documentation:
3. Initialization and initial condition (IC) perturbations
3.1 Atmosphere and land
| Hindcast | Forecast | |
|---|---|---|
| Atmosphere initialization | Every 5th day of the calendar month from Climate Forecast System Reanalysis (CFSR) | Everyday from Climate Forecast System Reanalysis (CFSR) |
| Atmosphere IC perturbations | Forecasts are initialized from each 6 hourly analysis cycle. No additional perturbations are added to the analysis. | Same as for the hindcast. |
Land Initialization | From the Climate Forecast System Reanalysis (CFSR) | From the Climate Forecast System Reanalysis (CFSR) |
| Land IC perturbations | No explicit perturbations added. | No explicit perturbations added. |
| Soil moisture initialization | From the Climate Forecast System Reanalysis (CFSR) | From the Climate Forecast System Reanalysis (CFSR) |
| Snow initialization | From the Climate Forecast System Reanalysis (CFSR) | From the Climate Forecast System Reanalysis (CFSR) |
| Unperturbed control forecast? | None | None |
Data assimilation method for control analysis: Climate Forecast System Reanalysis (CFSR); 3DVAR
Horizontal and vertical resolution of perturbations: N/A
Perturbations in +/- pairs: N/A
Detailed documentation:
3.2 Ocean and cryosphere
| Hindcast | Forecast | |
|---|---|---|
| Ocean initialization | CFSR | CFSR |
| Ocean IC perturbations | No explicit perturbations added to the analysis | No explicit perturbations added to the analysis |
| Unperturbed control forecast? | None | None |
Detailed documentation:
4. Model Uncertainties perturbations:
| Model dynamics perturbations | No |
|---|---|
| Model physics perturbations | No |
If there is a control forecast, is it perturbed? | No |
Detailed documentation:
5. Forecast system and hindcasts
| Forecast frequency | Every day |
|---|---|
| Forecast ensemble size | Four/day |
| Hindcast years | 1981-2010 |
| Hindcast ensemble size | Four/start date |
| Hindcast start dates | Every 5 days (see full list below) |
| On-the-fly or static hindcast set? | Static hindcast |
6. Other relevant information
The available hindcast start dates are as follows:
| Start Month | Available Start Days |
|---|---|
| January | 1, 6, 11, 16, 21, 26 and 31 |
| February | 5, 10, 15, 20 and 25 |
| March | 2, 7, 12, 17, 22 and 27 |
| April | 1, 6, 11, 16, 21 and 26 |
| May | 1, 6, 11, 16, 21, 26 and 31 |
| June | 5, 10, 15, 20, 25 and 30 |
| July | 5, 10, 15, 20, 25 and 30 |
| August | 4, 9, 14, 19, 24 and 29 |
| September | 3, 8, 13, 18, 23 and 28 |
| October | 3, 8, 13, 18, 23 and 28 |
| November | 2, 7, 12, 17, 22 and 27 |
| December | 2, 7, 12, 17, 22 and 27 |
7. Where to find more information
General information:
Comprehensive description of the model components:
Ek, M. B., K. E. Mitchell, Y. Lin, E. Rogers, P. Grunmann, V. Koren, G. Gayno, and J. D. Tarplay, 2003: Implementation of Noah land surface model advances in the National Centers for Environmental Prediction operational mesoscale Eta model. J. Geophys. Res., 108, 8851, doi:10.1029/2002JD003296.
Kumar, A., and Co-authors, 2012: An Analysis of the Non-stationarity in the Bias of Sea Surface Temperature Forecasts for the NCEP Climate Forecast System (CFS) Version 2. Mon. Wea. Rev., 140 ,3003-3016. https://journals.ametsoc.org/doi/full/10.1175/MWR-D-11-00335.1
Saha, S., and Coauthors, 2010: The NCEP Climate Forecast System Reanalysis. Bull. Amer. Meteor. Soc., 91, 1015.1057. doi: 10.1175/2010BAMS3001.1
Saha, S. and Coauthors, 2014: The NCEP Climate Forecast System Version 2 J. Climate, 27, 2185–2208. doi: http://dx.doi.org/10.1175/JCLI-D-12-00823.1
Zobler, L. 1986. A World Soil File for Global Climate Modelling. NASA Technical Memorandum 87802. NASA Goddard Institute for Space Studies, New York, New York, U.S.A.
