Description of the upgrade
ECMWF introduced an extra set of product fields in order to address an issue that occurs at day 10 in accumulated fields of the ensemble forecast (ENS). The additional products are available through dissemination under the name Ensemble Forecast Overlap (EFOV).
The issue was caused by the change in ENS horizontal resolution from higher resolution in leg 1 (0 to 240 hours) to lower resolution in leg 2 (246 to 360 hours). The change in resolution creates incorrect values for accumulations that run across day 10, i.e. those that span forecast time steps 240-246 hours.
The full list of ensemble forecast overlap fields available
| Surface runoff (variable resolution) | srovar | m | 230008 |
| Sub-surface runoff (variable resolution) | ssrovar | m | 230009 |
| Total sky direct solar radiation at surface (variable resolution) | fdirvar | J m**-2 | 230021 |
| Clear-sky direct solar radiation at surface (variable resolution) | cdirvar | J m**-2 | 230022 |
| Stratiform precipitation (Large-scale precipitation) (variable resolution) | lspvar | m | 230142 |
| Convective precipitation (variable resolution) | cpvar | m | 230143 |
| Snowfall (convective + stratiform) (variable resolution) | sfvar | m of water equivalent | 230144 |
| Boundary layer dissipation (variable resolution) | bldvar | J m**-2 | 230145 |
| Surface sensible heat flux (variable resolution) | sshfvar | J m**-2 | 230146 |
| Surface latent heat flux (variable resolution) | slhfvar | J m**-2 | 230147 |
| Surface solar radiation downwards (variable resolution) | ssrdvar | J m**-2 | 230169 |
| Surface thermal radiation downwards (variable resolution) | strdvar | J m**-2 | 230175 |
| Surface net solar radiation (variable resolution) | ssrvar | J m**-2 | 230176 |
| Surface net thermal radiation (variable resolution) | strvar | J m**-2 | 230177 |
| Top net solar radiation (variable resolution) | tsrvar | J m**-2 | 230178 |
| Top net thermal radiation (variable resolution) | ttrvar | J m**-2 | 230179 |
| East-West surface stress (variable resolution) | ewssvar | N m**-2 s | 230180 |
| North-South surface stress (variable resolution) | nsssvar | N m**-2 s | 230181 |
| Evaporation (variable resolution) | evar | kg m**-2 | 230182 |
| Sunshine duration (variable resolution) | sundvar | s | 230189 |
| Longitudinal component of gravity wave stress (variable resolution) | lgwsvar | N m**-2 s | 230195 |
| Meridional component of gravity wave stress (variable resolution) | mgwsvar | N m**-2 s | 230196 |
| Gravity wave dissipation (variable resolution) | gwdvar | J m**-2 | 230197 |
| Skin reservoir content (variable resolution) | srcvar | kg m**-2 | 230198 |
| Runoff (variable resolution) | rovar | m | 230205 |
| Total precipitation (variable resolution) | tpvar | m | 230228 |
Further reading
- A comprehensive description of the Ensemble system and its variable resolution (leg 1 and leg 2) can be found in Newsletter 108 (pp 14-20).
Changes in GRIB API
Support for two following parameters was added to GRIB API.
- fdirvar = Total sky direct solar radiation at surface (variable resolution)
- cdirvar = Clear-sky direct solar radiation at surface (variable resolution)
Implemented: 21 November 2012 |
Resolution
Unchanged