For ERA-Interim (1st January 1979 to 31st August 2019) access through the ECMWF Web API stopped on 01 June 2023 Its successor ERA5 is available from the Climate Data Store (CDS) (What are the changes from ERA-Interim to ERA5?) and users are strongly advised to migrate to ERA5 (How to download ERA5). For those users who still need access to ERA-Interim after 01 June 2023 (subject to further notice), they can do so via the Climate Data Store (CDS) API. |
ERA-Interim and ERA-Interim/Land are two ECMWF Re-Analysis datasets. The main difference between ERA-interim and ERA-Interim/Land is the version of the TESSEL land-surface model (Tiled ECMWF Scheme for Surface Exchanges over Land).
ERA-Interim/Land is produced using the Hydrology-Tiled ECMWF Scheme for Surface Exchanges over Land (HTESSEL) model with meteorological forcing from ERA-Interim and precipitation adjustments based on GPCP v2.1 (dataset merges satellite and rain gauge (SG) data from a number of satellite sources). This scheme is an extension of the TESSEL scheme (van den Hurk et al., 2000) that was used in ERA-Interim, which was based on a 2006 version of ECMWF’s operational Integrated Forecasting System (IFS).
HTESSEL includes an improved soil hydrology (Balsamo et al., 2009), a new snow scheme (Dutra et al., 2010), a multi-year satellite-based vegetation climatology (Boussetta et al., 2011), and a revised bare-soil evaporation (Balsamo et al., 2011; Albergel et al., 2012a).
Both ERA/Interim and ERA-Interim/Land use four soil depth layers as follows:
| Level | Top (m) | Bottom (m) | Thickness (m) |
|---|---|---|---|
| 1 | 0.0 | 0.07 | 0.07 |
| 2 | 0.07 | 0.28 | 0.21 |
| 3 | 0.28 | 1 | 0.72 |
| 4 | 1 | 2.89 | 1.89 |
Soil moisture is available in both datasets with values typically between 0.1 and 0.4 in cubic meter water per cubic meter volume. ERA-Interim/Land should be preferred over ERA-Interim and make sure to select 'Analysis' when downloading the ERA-Interim/Land data.
For detailed documentation see Balsamo et al., 2012.
Reference
Albergel C., G. Balsamo, P. de Rosnay, J. Muñoz-Sabater and S. Boussetta, 2012a: A bare ground evaporation revision in the ECMWF land-surface scheme: evaluation of its impact using ground soil moisture and satellite microwave data, ECMWF Tech. Memo 685, 26pp., https://www.ecmwf.int/node/7671.
Balsamo, G., P. Viterbo, A. Beljaars, B. van den Hurk, M. Hirschi, A.K. Betts and K. Scipal, 2009: A revised hydrology for the ECMWF model: Verification from field site to terrestrial water storage and impact in the Integrated Forecast System, J. Hydrometeor., 10, 623–643, doi: 10.21957/yzyeh0vlw .
Balsamo, G., S. Boussetta, E. Dutra, A. Beljaars, P. Viterbo, and B. Van den Hurk, 2011: Evolution of land surface processes in the IFS, ECMWF Newsletter, 127, 17-22, doi: 10.21957/x1j3i7bz.
Balsamo and,Coauthors, 2012: ERA-Interim/Land: A global land-surface reanalysis based on ERA-Interim meteorological forcing. ECMWF ERA Report Series 13, 25 pp, https://www.ecmwf.int/node/7922
Boussetta, S., G. Balsamo, A. Beljaars and J. Jarlan, 2011: Impact of a satellite-derived Leaf AreaIndex monthly climatology in a global Numerical Weather Prediction model, ECMWF Tech. Memo. 640, 30 pp.,doi: 10.21957/h7n0ilfkp
Dutra, E., G. Balsamo, P. Viterbo, P. Miranda, A. Beljaars, C. Schär and K. Elder, 2010: An improved snow scheme for the ECMWF land surface model: description and offline validation, J. Hydrometeor., 11, 899-916, doi: 10.1175/2010JHM1249.1
van den Hurk, B., P. Viterbo, A. Beljaars and A.K. Betts, 2000: Offline validation of the ERA-40 surface scheme, ECMWF Tech. Memo. 295,44 pp., doi: 10.21957/9aoaspz8
This document has been produced in the context of the Copernicus Climate Change Service (C3S). The activities leading to these results have been contracted by the European Centre for Medium-Range Weather Forecasts, operator of C3S on behalf of the European Union (Delegation agreement signed on 11/11/2014). All information in this document is provided "as is" and no guarantee or warranty is given that the information is fit for any particular purpose. The users thereof use the information at their sole risk and liability. For the avoidance of all doubt, the European Commission and the European Centre for Medium-Range Weather Forecasts have no liability in respect of this document, which is merely representing the author's view. |