Input data set: ERA5

Protocol relation: Protocol
Data Type: Observed atmospheric climate
Simulation rounds: Not yet active

ERA5 global meteorological forcing data processed for ISIMIP2a. Original ERA5 data were aggregated in space and time to 0.5° and temporal resolution, respectively. Prior to that aggregation, near-surface wind speed, relative and specific humidity were derived from available ERA5 variables: Near-surface wind speed was computed from near-surface easterly and northerly wind components. Near-surface relative and specific humidity were computed from surface air pressure, near-surface air temperature and near-surface dew point using the equations of Buck (1981, doi:10.1175/1520-0450(1981)020<1527:NEFCVP>2.0.CO;2) as described in Buck Research CR-1A User's Manual, Appendix 1 (

Scenarios: hist-obs
Variables: tasmax, tas, tasmin, rlds, hurs, huss, wind, rsds, prsn, ps, pr
Data source

ERA5 reanalysis data at 0.25° spatial and hourly temporal resolution (

ERA5 global meteorological forcing data processed for ISIMIP2a contains modified Copernicus Climate Change Service Information [2019]. Neither the European Commission nor ECMWF is responsible for any use that may be made of the Copernicus Information or Data it contains. For more information see

All users of Copernicus Products must provide clear and visible attribution to the Copernicus programme. For more information about the Copernicus C3S/CAMS License agreement, see:

Download Instructions

For ISIMIP participants, these files are available for download on the DKRZ server using the path /ISIMIP/ISIMIP2a/InputData/climate_co2/climate/HistObs/ERA5/.

For external users, these data are available on the ISIMIP ESGF server ( In specific cases, you can also access this data via an rsync facility (described here:, for which the password will be provided upon request (