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ICDC
CENIntegrated Climate Data Center ICDC

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ECMWF ERA-5 - European Reanalysis

Global 2 m Temperature from ECMWF's ERA5 at 1st January 1979 0:00h
Global 2 m Temperature from ECMWF's ERA5 at 1st January 1979 0:00h. Copyright: UHH/CEN/AJB

Topics

Access

RESTRICTED:

RESTRICTED: This link to the data set is only available for a restricted user group.  The data set is only accessible in CEN/MPI net or accessible from external nets with a customer account.  Please contact ICDC if you would like to access this data from outside the network.

  • Data access via file system in UHH Network: /data/icdc/reanalyses/era5
  • Data access via file system in DKRZ Network: /pool/data/ERA5

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Description

ERA-5 is a global atmospheric reanalysis that was developed by the Copernicus Climate Change Service (C3S) and produced at the "European Centre for Medium-Range Weather Forecasts" (ECMWF). It replaces the four previous reanalyses FGGE, ERA-15, ERA-40 and ERA-Interim. ICDC offers a subset of the data for internal use. The DKRZ offers a larger subset of the ERA5 data in GRIB format.

The ECMWF model Earth System model IFS, cycle 41r2 was used for data processing. This type of model is also used for weather forecasting and is constantly being developed over time. TThe continuous use of a model for a reanalysis data set results in a homogeneous database. In the reanalysis, in addition to the routine measurements, further quality-assured observation data are included (assimilated) in the calculation with the model, which are not included into the routine forecast. These assimilated observational data come from a variety of sources, such as weather stations, radiosonde ascents, ship measurements and, since the 1970s, satellite measurements. Reanalyses are model data based on real measurements with a very good spatial and temporal resolution and are used for a variety of scientific analyzes.

The ERA-5 reanalysis period currently begins in 1979 and is continuously updated so that the latest data from approximately 3 months prior to today is available from the ECMWF. It is planned to continue ERA-5 until the reanalysis is replaced by the next ERA-6, as well as to expand it into the past up to 1950. ERA-5 uses the same 37 pressure levels as ERA-Interim. The time resolution is 1 to 3 hours depending on the parameter. The reanalyses are not calculated on a Cartesian grid, but on a reduced Gaussian grid with a resolution of up to N320.

Due to the size of the data, ICDC initially only offers selected surface parameters for the period 1979 to 2019. The following information only refers to the data sets offered by ICDC:

ICDC currently only offers surface parameters. Some parameters were calculated by the ECMWF in the model as analysis data (0:00 am), others as forecast (6:00 am). The data was obtained from the ECMWF as a data package in GRIB format and extracted with the ECMWF EcCodes routines (grib_filter, grib_to_netcdf) and converted into the NetCDF format. The parameters were extracted with the CDO routines.

The DKRZ offers a larger subset of the ERA5 data at various levels in GRIB format.

Last update of data set at ICDC: JAN 2020

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Parameters

Parameters of the ERA5 data set
ParameterAbbreviationUnitNumber
Convective precipitation cp m 143
Convective rain rate crr kg m**-2 s**-1 228218
Convective snowfall rate water equivalent csfr kg m**-2 s**-1 228220
2 metre dewpoint temperature D2M K 168
Large-scale precipitation lsp m 142
Large scale rain rate lsrr kg m**-2 s**-1 228219
Large scale snowfall rate water equivalent lssfr kg m**-2 s**-1 228221
Mean convective precipitation rate mcpr kg m**-2 s**-1 235030
Mean surface downward long-wave radiation flux msdwlwrf W m**-2 235036
Mean surface downward short-wave radiation flux msdwswrf W m**-2 235035
Mean sea-level pressure MSL Pa 151
Precipitation type ptype see code table (4.201) 260015
Surface Pressure SP Pa 134
Surface solar radiation downwards ssrd J m**-2 169
Surface thermal radiation downwards strd J m**-2 175
2 metre temperature T2M K 167
Total column rain water tcrw kg m**-2 228089
Total precipitation tp m 228
10 metre U wind component U10M m s**-1 165
10 metre V wind component V10M m s**-1 166

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Coverage, spatial and temporal resolution

Period and temporal resolution:

  • 1979/01/01 0:00 UTC to 2019/12/31 23:00 UTC
  • 1-hourly

Coverage and spatial resolution:

  • Global
  • Spatial resolution: about 0,281°x0,281° corresponding to the N320 Gaussian Grid
  • surface

Format:

  • NetCDF
  • GRIB

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Data quality

These are model data based on measured data. Possible sources of errors are faulty measured data that are assimilated into the model, as well as simplifications or even errors in the model. The quality of the data assimilation has been improved significantly compared to ERA40 and ERA-Interim and the model has a high quality. For more details about the uncertainty estimation have a look at ECMWF's ERA5: uncertainty estimation (see references).

By transforming the data from the Gaussian grid into geographic coordinates, a small interpolation effect has to be taken into account.

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Contact

Annika Jahnke-Bornemann

ICDC / CEN / University of Hamburg
E-Mail: annika.jahnke-bornemann"AT"uni-hamburg.de

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References

Literature:

  • Hersbach, H, Bell, B, Berrisford, P, et al. The ERA5 global reanalysis. Q J R Meteorol Soc. 2020; 146: 1999– 2049. https://doi.org/10.1002/qj.3803 , data was provided by ICDC, CEN, University of Hamburg in June 2020.

Websites:

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Data citation, License, and Acknowledgments

Please cite the data as follows:

Hersbach, H, Bell, B, Berrisford, P, et al. The ERA5 global reanalysis. Q J R Meteorol Soc. 2020; 146: 1999– 2049. https://doi.org/10.1002/qj.3803, data was provided by ICDC, CEN, University of Hamburg in June 2020..

and with the following acknowledgments:

Thanks to ICDC, CEN, University of Hamburg for data support.

License

You can find license information on the ECMWF project page.

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