Here we document the ERA5 dataset, which, eventually, will cover the period from January 1950 onwards. Complete ERA5 data released so far covers the period from 1979 and continues to be extended forward in near real time. For up to date information on ERA5, please consult the C3S Announcements on the Copernicus user forum.
ERA5 is produced using 4D-Var data assimilation and model forecasts in CY41R2 of the ECMWF Integrated Forecast System (IFS), with 137 hybrid sigma/pressure (model) levels in the vertical and the top level at 0.01 hPa. Atmospheric data are available on these levels and they are also interpolated to 37 pressure, 16 potential temperature and 1 potential vorticity level(s) by FULL-POS in the IFS. "Surface or single level" data are also available, containing 2D parameters such as precipitation, top of atmosphere radiation and vertical integrals over the entire depth of the atmosphere. The atmospheric model in the IFS is coupled to a land-surface model (HTESSEL), which produces parameters such as 2m temperature and soil temperatures, and an ocean wave model (WAM), the parameters of which are also designated as surface or single level parameters.
The ERA5 dataset contains one (hourly, 31 km) high resolution realisation (referred to as "reanalysis" or "HRES") and a reduced resolution ten member ensemble (referred to as "ensemble" or "EDA"). The ensemble is required for the data assimilation procedure, but as a by-product also provides an estimate of the relative, random uncertainty. Generally, the data are available at a sub-daily and monthly frequency and consist of analyses and short (18 hour) forecasts, initialised twice daily from analyses at 06 and 18 UTC. Most analysed parameters are also available from the forecasts. However, there are a number of forecast parameters, e.g. mean rates/fluxes and accumulations, that are not available from the analyses.
The data are archived in the ECMWF data archive (MARS) and a pertinent sub-set of the data, interpolated to a regular latitude/longitude grid, has been copied to the C3S Climate Data Store (CDS) disks. On the CDS disks, where single level and pressure level data are available, analyses are provided rather than forecasts, unless the parameter is only available from the forecasts.
ERA5.1 is a re-run of ERA5, for the years 2000 to 2006 only, and was produced to improve upon the cold bias in the lower stratosphere seen in ERA5 during this period.
An ERA5 back extension 1950-1978 (Preliminary version) has been produced. Although in many other respects the quality is relatively good, this preliminary data does suffer from excessively intense tropical cyclones. This dataset is available as a separate entry in the CDS catalogue (and in MARS) for a short period of time, after which it will be deprecated and replaced by a new updated version which will be accessible through the main ERA5 entry. The main entry currently contains data from 1979 onwards.
Model level parameters are archived in GRIB2 format. All other parameters are in GRIB1 unless otherwise indicated, see Parameter listings.
In the CDS, there is the option of retrieving the data in netCDF format.
Initial release data, i.e. data no more than three months behind real time, is called ERA5T. In the event that serious flaws are detected in ERA5T, this data could be different to the final ERA5 data. In practice, though, this will be very unlikely to occur. Based on experience with the production of ERA5 so far (and ERA-Interim in the past), our expectation is that such an event would not occur more than once every few years, if at all. In the unlikely event that such a correction is required, users will be notified as soon as possible.
For the CDS, daily updates are available about 5 days behind real time and monthly mean updates are available about 5 days after the end of the month.
Note: At the moment the timing of the availability of ERA5T data on the CDS on a daily basis can vary. We do not work to a specific target schedule. However, the D-5 data are typically available by 12UTC, but not guaranteed. We are working on reducing the variability of the time of availability, but this may take several months to achieve.
For MARS ERA5 data, monthly updates are available about two months after the month in question.
For GRIB data, ERA5T can be identified by the key expver=0005 in the GRIB header. ERA5 is identified by the key expver=0001.
For netCDF data requests which return just ERA5 or just ERA5T data, there is no means of differentiating between ERA5 and ERA5T data in the resulting netCDF files.
For netCDF data requests which return a mixture of ERA5 and ERA5T data, the origin of the variables (1 or 5) will be identifiable in the resulting netCDF files. See the link for more details.
For ERA5, the IFS documentation for CY41R2 should be used.
The 4D-Var data assimilation uses 12 hour windows from 09 UTC to 21 UTC and 21 UTC to 09 UTC (the following day).
The model time step is 12 minutes for the HRES and 20 minutes for the EDA, though occasionally these numbers are adjusted to cope with instabilities.
The full ERA5 and ERA5T datasets are held in the ECMWF data archive (MARS) and a pertinent sub-set of these data, interpolated to a regular latitude/longitude grid, has been copied to the C3S Climate Data Store (CDS) disks. ERA5.1 is not available from the CDS disks, but is available from MARS (for advice on using ERA5.1 in conjunction with ERA5, CDS data, see "ERA5: mixing CDS and MARS data" in ERA5: data documentation#Guidelines). On the CDS disks, where most single level and pressure level parameters are available, analyses are provided rather than forecasts, unless the parameter is only available from the forecasts.
ERA5 data on the CDS disks can be downloaded either from the relevant CDS download page or using the CDS API.
Getting data from the CDS disks provides the fastest access to ERA5.
ERA5 data in MARS can be accessed using the CDS API, but access is relatively slow.
NOTE: MARS has stream and type, CDS only has product type. MARS has levtype but CDS puts that into the dataset. eg product_type=ensemble_spread is given by stream=enda or ewda, type=es, levtype=sfc or pl (not for ewda). |
ERA5 data on the CDS disks can be downloaded either from the relevant CDS download page or, for larger data volumes in particular, using the CDS API. Subdivisions of the data are labelled using dataset and product_type. Datasets reanalysis-era5-single-levels and reanalysis-era5-pressure-levels contain the following (sub-daily) product types:
Datasets reanalysis-era5-single-levels-monthly-means and reanalysis-era5-pressure-levels-monthly-means contain the following (monthly) product types:
Datasets reanalysis-era5-single-levels-preliminary-back-extension and reanalysis-era5-pressure-levels-preliminary-back-extension contain the following (sub-daily) product types:
Datasets reanalysis-era5-single-levels-monthly-means-preliminary-back-extension and reanalysis-era5-pressure-levels-monthly-means-preliminary-back-extension contain the following (monthly) product types:
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ERA5 data in MARS can be accessed with the CDS API by specifying dataset whereas member state users can access data in MARS by specifying class and expver, according to the following table:
Subdivisions of the data are labelled using the keywords stream, type and levtype: Stream:
Type:
Levtype:
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Documentation is available on How to download ERA5.
In MARS: the date and time of the data is specified with three MARS keywords: date, time and (forecast) step. For analyses, step=0 hours so that date and time specify the analysis date/time. For forecasts, date and time specify the forecast start time and step specifies the number of hours since that start time. The combination of date, time and step defines the validity date/time. For analyses, the validity date/time is equal to the analysis date/time.
In the CDS: analyses are provided rather than forecasts, unless the parameter is only available from the forecasts. The date and time of the data is specified using the validity date/time, so step does not need to be specified. For forecasts, steps between 1 and 12 hours have been used to provide data for all the validity times in each 24 hours, see Table 0 below.
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For sub-daily data for the HRES (stream=oper/wave) the analyses (type=an) are available hourly. The short forecasts, run twice daily from 06 and 18 UTC, provide hourly output forecast steps from 0 to 18 hours (only steps 1 to 12 hours are available on the CDS disks). For the EDA, the sub-daily non-wave data (stream=enda) are available every 3 hours but the sub-daily wave data (stream=ewda) are available hourly in MARS and 3 hourly on the CDS disks.
The ERA5 HRES atmospheric data has a resolution of 31km, 0.28125 degrees, and the EDA has a resolution of 63km, 0.5625 degrees. (Depending on the parameter, the data are archived either as spectral coefficients with a triangular truncation of T639 (HRES) and T319 (EDA) or on a reduced Gaussian grid with a resolution of N320 (HRES) and N160 (EDA). These grids are so called "linear grids", sometimes referred to as TL639 (HRES) and TL319 (EDA).)
The wave data are produced and archived on a different grid to that of the atmospheric model, namely a reduced latitude/longitude grid with a resolution of 0.36 degrees (HRES) and 1.0 degrees (EDA).
ERA5 data available from the CDS disks has been pre-interpolated to a regular latitude/longitude grid appropriate for that data.
The article Model grid box and time step might be useful.
In order to define the surface geopotential in ERA5, the IFS uses surface elevation data interpolated from a combination of SRTM30 and other surface elevation datasets. For more details please see the IFS documentation, Cycle 41r2, Part IV. Physical processes, section 11.2.2 Surface elevation data at 30 arc seconds.
The IFS assumes the Earth is a perfect sphere, but the geodetic latitude/longitude of the surface elevation datasets are used as if they were the spherical latitude/longitude of the IFS.
ECMWF data is referenced in the horizontal with respect to the WGS84 ellipse (which defines the major/minor axes) but in the vertical it is referenced to the Geoid (EGM96).
For data in GRIB1 format the earth model is a sphere with radius = 6367.47 km, as defined in the WMO GRIB Edition 1 specifications, Table 7, GDS Octet 17
For data in GRIB2 format the earth model is a sphere with radius = 6371.2290 km, as defined in the WMO GRIB2 specifications, section 2.2.1, Code Table 3.2, Code figure 6.
For data in NetCDF format (i.e. converted from the native GRIB format to NetCDF), the earth model is inherited from the GRIB data.
ERA5 is produced using 4D-Var data assimilation and model forecasts in CY41R2 of the IFS. The 4D-Var in ERA5 utilises 12 hour assimilation windows from 9-21 UTC and 21-9 UTC, where the background forecast and all the observations falling within a time window are used to specify all the analyses during that window. However, the accuracy of the analyses is not uniform throughout each window. If the model and observations are unbiased and their errors follow Gaussian distributions and if the observations are homogeneous in space and time, then the analysis error will be smallest in the middle of the assimilation window. However, because none of these assumptions are actually true in the IFS, the particular parameter and location of interest are important, too. Knowing that, a careful study should show at which points during the assimilation windows the analysis is most accurate.
The 10 member ensemble is required for the data assimilation procedure. However, as a useful by-product, this ensemble also provides an estimate of the relative, random uncertainty. The "spread" of the 10 member ensemble, encapsulated by the standard deviation, provides a measure of this uncertainty and is larger for time periods and spatial locations where the uncertainty is relatively large and is smaller when and where there is more certainty in the analysed/forecast values. The spread is a measure of the relative uncertainty, so the numbers do not provide the absolute uncertainty. On the whole, the uncertainty becomes larger as you go back in time, when the observing system was not as good as in the present day, and in data sparse locations such as the pre-satellite era, southern hemisphere. In general, apart from that for the sea surface temperature, the spread does not represent systematic uncertainty, only random, or "synoptic", uncertainty. For more information, see ERA5: uncertainty estimation.
All the analysed parameters and many of the forecast parameters are described as "instantaneous". For more information on what instantaneous means, see Parameters valid at the specified time. Such instantaneous parameters may, or may not, have been averaged in time, to produce monthly means.
Such parameters, which are only available from forecasts, have undergone particular types of statistical processing (temporal mean or accumulation, respectively) over a period of time called the processing period. In addition, these parameters may, or may not, have been averaged in time, to produce monthly means.
The accumulations (over the accumulation/processing period) in the short forecasts (from 06 and 18 UTC) of ERA5 are treated differently compared with those in ERA-Interim and operational data (where the accumulations are from the beginning of the forecast to the validity date/time). In the short forecasts of ERA5, the accumulations are since the previous post processing (archiving), so for:
Mean rate/flux parameters in ERA5 (e.g. Table 4 for surface and single levels) provide similar information to accumulations (e.g. Table 3 for surface and single levels), except they are expressed as temporal means, over the same processing periods, and so have units of "per second".
Note that:
The short forecasts of ERA5 contain some surface and single level parameters that are the minimum or maximum value since the previous post processing (archiving), see Table 5 below. So, for:
The ocean wave model used in ERA5 (WAM, which is included in the IFS) provides wave spectra with 24 directions and 30 frequencies (see "2D wave spectra (single)", Table 7).
Download from ERA5 ERA5 wave spectra data is not available from the CDS disks. However, it is available in MARS and can be accessed through the CDS API. For more information see Data organisation and how to download ERA5 and How to download ERA5 (Option B: Download ERA5 family data that is NOT listed in the CDS online catalogue - SLOW ACCESS. Decoding 2D wave spectra in GRIB To decode wave spectra in GRIB format we recommend ecCodes. Wave spectra are encoded in a specific way that other tools might not decode correctly. In GRIB, the parameter is called 2d wave spectra (single) because in GRIB, the data are stored as a single global field per each spectral bin (a given frequency and direction), but in NetCDF, the fields are nicely recombined to produce a 2d matrix representing the discretized spectra at each grid point. The wave spectra are encoded in GRIB using a local table specific to ECMWF. Because of this, the conversion of the meta data containing the information about the frequencies and the directions are not properly converted from GRIB to NetCDF format. So rather than having the actual values of the frequencies and directions, values show index numbers (1,1) : first frequency, first direction, (1,2) first frequency, second direction, etc .... Also note that it is NOT the spectral density that is encoded but rather log10 of it, so to recover the spectral density, expressed in m^2 /(radian Hz), one has to take the power 10 (10^) of the NON missing decoded values. Missing data are for all land points, but also, as part of the GRIB compression, all small values below a certain threshold have been discarded and so those missing spectral values are essentially 0. m^2 /(gradient Hz). Decoding 2D wave spectra in NetCDF The NetCDF wave spectra file will have the dimensions longitude, latitude, direction, frequency and time. However, the direction and frequency bins are simply given as 1 to 24 and 1 to 30, respectively. The direction bins start at 7.5 degree and increase by 15 degrees until 352.5, with 90 degree being towards the east (Oceanographic convention). The frequency bins are non-linearly spaced. The first bin is 0.03453 Hz and the following bins are: f(n) = f(n-1)*1.1; n=2,30. The data provided is the log10 of spectra density. To obtain the spectral density one has to take to the power 10 (10 ** data). This will give the units 2D wave spectra as m**2 s radian**-1 . Very small values are discarded and set as missing values. These are essentially 0 m**2 s radian**-1. This recoding can be done with the Python xarray package, for example:
Units of 2D wave spectra Once decoded, the units of 2D wave spectra are m2 s radian-1 |
In addition to the sub-daily data, most parameters are also available as monthly means. For the surface and single level parameters, there are some exceptions which are listed in Table 8.
Monthly means are available in two forms:
Monthly means for:
The accumulations in monthly means (of daily means, stream=moda/edmo) have been scaled to have an "effective" processing period of one day, so for accumulations in these streams:
For the EDA sub-daily data (stream=enda/ewda), compared with HRES sub-daily data (stream=oper/wave), ensemble means and standard deviations (type=em/es) are also available. Both these quantities are calculated from all the 10-members (i.e., including the control).
Ensemble standard deviation is often referred to as ensemble spread and is calculated with respect to the ensemble mean. The ensemble standard deviation is not the sample stdv, so we divide by 10 rather than 9 (N-1).
Ensemble means and standard deviations contain analysed parameters when step=0, otherwise they contain forecast parameters. However, only surface and pressure level data (levtype=sfc/pl) contain forecast steps beyond 3 hours. There are no monthly means for ensemble means and standard deviations.
Pressure levels: 1000/975/950/925/900/875/850/825/800/775/750/700/650/600/550/500/450/400/350/300/250/225/200/175/150/125/100/70/50/30/20/10/7/5/3/2/1
Potential temperature levels: 265/275/285/300/315/320/330/350/370/395/430/475/530/600/700/850
Potential vorticity level: 2000
Model levels: 1/to/137, which are described at https://www.ecmwf.int/en/forecasts/documentation-and-support/137-model-levels and ERA5: compute pressure and geopotential on model levels, geopotential height and geometric height. The model levels are hybrid pressure/sigma. For more information, see the documentation of the underlying model, ECMWF's IFS, CY41R2, Part III. Dynamics and numerical procedures, Chapter 2 Basic equations and discretisation.
Tables 1-6 below describe the surface and single level parameters (levtype=sfc), Table 7 describes wave parameters, Table 8 describes the monthly mean exceptions for surface and single level and wave parameters and Tables 9-13 describe upper air parameters on various levtypes.
Information on all ECMWF parameters (e.g. columns shortName and paramId) is available from the ECMWF parameter database
(stream=oper/enda/mnth/moda/edmm/edmo, levtype=sfc)
count | name | units | Variable name in CDS | shortName | paramId | an | fc |
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1 | (0 - 1) | lake_cover | cl | 26 | x | x | |
2 | m | lake_depth | dl | 228007 | x | x | |
3 | (0 - 1) | low_vegetation_cover | cvl | 27 | x | ||
4 | (0 - 1) | high_vegetation_cover | cvh | 28 | x | ||
5 | ~ | type_of_low_vegetation | tvl | 29 | x | ||
6 | ~ | type_of_high_vegetation | tvh | 30 | x | ||
7 | ~ | soil_type | slt | 43 | x | ||
8 | m | standard_deviation_of_filtered_subgrid_orography | sdfor | 74 | x | ||
9 | m**2 s**-2 | geopotential | z | 129 | x | x | |
10 | ~ | standard_deviation_of_orography | sdor | 160 | x | ||
11 | ~ | anisotropy_of_sub_gridscale_orography | isor | 161 | x | ||
12 | radians | angle_of_sub_gridscale_orography | anor | 162 | x | ||
13 | ~ | slope_of_sub_gridscale_orography | slor | 163 | x | ||
14 | (0 - 1) | land_sea_mask | lsm | 172 | x | x |
1Soil type (texture) determines the saturation, field capacity and permanent wilting point at all the soil levels, see Table 8.9 in Chapter 8 Surface parametrization, Part IV Physical Processes of the IFS documentation (CY41R2 for ERA5).
(stream=oper/enda/mnth/moda/edmm/edmo, levtype=sfc)
count | name | units | Variable name in CDS | shortName | paramId | an | fc |
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1 | J kg**-1 | convective_inhibition | cin | 228001 | x | ||
2 | m s**-1 | friction_velocity | zust | 228003 | x | ||
3 | K | lake_mix_layer_temperature | lmlt | 228008 | x | x | |
4 | m | lake_mix_layer_depth | lmld | 228009 | x | x | |
5 | K | lake_bottom_temperature | lblt | 228010 | x | x | |
6 | K | lake_total_layer_temperature | ltlt | 228011 | x | x | |
7 | dimensionless | lake_shape_factor | lshf | 228012 | x | x | |
8 | K | lake_ice_temperature | lict | 228013 | x | x | |
9 | m | lake_ice_depth | licd | 228014 | x | x | |
10 | (0 - 1) | uv_visible_albedo_for_direct_radiation | aluvp | 15 | x | x | |
11 | Minimum vertical gradient of refractivity inside trapping layer | m**-1 | minimum_vertical_gradient_of_refractivity_inside_trapping_layer | dndzn | 228015 | x | |
12 | (0 - 1) | uv_visible_albedo_for_diffuse_radiation | aluvd | 16 | x | x | |
13 | Mean vertical gradient of refractivity inside trapping layer | m**-1 | mean_vertical_gradient_of_refractivity_inside_trapping_layer | dndza | 228016 | x | |
14 | (0 - 1) | near_ir_albedo_for_direct_radiation | alnip | 17 | x | x | |
15 | m | duct_base_height | dctb | 228017 | x | ||
16 | (0 - 1) | near_ir_albedo_for_diffuse_radiation | alnid | 18 | x | x | |
17 | m | trapping_layer_base_height | tplb | 228018 | x | ||
18 | m | trapping_layer_top_height | tplt | 228019 | x | ||
19 | m | cloud_base_height | cbh | 228023 | x | ||
20 | m | zero_degree_level | deg0l | 228024 | x | ||
21 | m s**-1 | instantaneous_10m_wind_gust | i10fg | 228029 | x | ||
22 | (0 - 1) | sea-ice_cover | ci | 31 | x | x | |
23 | (0 - 1) | snow_albedo | asn | 32 | x | x | |
24 | kg m**-3 | snow_density | rsn | 33 | x | x | |
25 | K | sea_surface_temperature | sst | 34 | x | x | |
26 | K | ice_temperature_layer_1 | istl1 | 35 | x | x | |
27 | K | ice_temperature_layer_2 | istl2 | 36 | x | x | |
28 | K | ice_temperature_layer_3 | istl3 | 37 | x | x | |
29 | K | ice_temperature_layer_4 | istl4 | 38 | x | x | |
30 | m**3 m**-3 | volumetric_soil_water_layer_1 | swvl1 | 39 | x | x | |
31 | m**3 m**-3 | volumetric_soil_water_layer_2 | swvl2 | 40 | x | x | |
32 | m**3 m**-3 | volumetric_soil_water_layer_3 | swvl3 | 41 | x | x | |
33 | m**3 m**-3 | volumetric_soil_water_layer_4 | swvl4 | 42 | x | x | |
34 | J kg**-1 | convective_available_potential_energy | cape | 59 | x | x | |
35 | m**2 m**-2 | leaf_area_index_low_vegetation | lai_lv | 66 | x | x | |
36 | m**2 m**-2 | leaf_area_index_high_vegetation | lai_hv | 67 | x | x | |
37 | m s**-1 | 10m_u-component_of_neutral_wind | u10n | 228131 | x | x | |
38 | m s**-1 | 10m_v-component_of_neutral_wind | v10n | 228132 | x | x | |
39 | Pa | surface_pressure | sp | 134 | x | x | |
40 | K | soil_temperature_level_1 | stl1 | 139 | x | x | |
41 | m of water equivalent | snow_depth | sd | 141 | x | x | |
42 | ~ | charnock | chnk | 148 | x | x | |
43 | Pa | mean_sea_level_pressure | msl | 151 | x | x | |
44 | m | boundary_layer_height | blh | 159 | x | x | |
45 | (0 - 1) | total_cloud_cover | tcc | 164 | x | x | |
46 | m s**-1 | 10m_u-component_of_wind | 10u | 165 | x | x | |
47 | m s**-1 | 10m_v-component_of_wind | 10v | 166 | x | x | |
48 | K | 2m_temperature | 2t | 167 | x | x | |
49 | K | 2m_dewpoint_temperature | 2d | 168 | x | x | |
50 | K | soil_temperature_level_2 | stl2 | 170 | x | x | |
51 | K | soil_temperature_level_3 | stl3 | 183 | x | x | |
52 | (0 - 1) | low_cloud_cover | lcc | 186 | x | x | |
53 | (0 - 1) | medium_cloud_cover | mcc | 187 | x | x | |
54 | (0 - 1) | high_cloud_cover | hcc | 188 | x | x | |
55 | m of water equivalent | skin_reservoir_content | src | 198 | x | x | |
56 | (0 - 1) | instantaneous_large_scale_surface_precipitation_fraction | ilspf | 228217 | x | ||
57 | kg m**-2 s**-1 | convective_rain_rate | crr | 228218 | x | ||
58 | kg m**-2 s**-1 | large_scale_rain_rate | lsrr | 228219 | x | ||
59 | kg m**-2 s**-1 | convective_snowfall_rate_water_equivalent | csfr | 228220 | x | ||
60 | kg m**-2 s**-1 | large_scale_snowfall_rate_water_equivalent | lssfr | 228221 | x | ||
61 | N m**-2 | instantaneous_eastward_turbulent_surface_stress | iews | 229 | x | x | |
62 | N m**-2 | instantaneous_northward_turbulent_surface_stress | inss | 230 | x | x | |
63 | W m**-2 | instantaneous_surface_sensible_heat_flux | ishf | 231 | x | x | |
64 | kg m**-2 s**-1 | instantaneous_moisture_flux | ie | 232 | x | x | |
65 | K | skin_temperature | skt | 235 | x | x | |
66 | K | soil_temperature_level_4 | stl4 | 236 | x | x | |
67 | K | temperature_of_snow_layer | tsn | 238 | x | x | |
68 | (0 - 1) | forecast_albedo | fal | 243 | x | x | |
69 | m | forecast_surface_roughness | fsr | 244 | x | x | |
70 | ~ | forecast_logarithm_of_surface_roughness_for_heat | flsr | 245 | x | x | |
71 | m s**-1 | 100m_u-component_of_wind | 100u | 228246 | x | x | |
72 | m s**-1 | 100m_v-component_of_wind | 100v | 228247 | x | x | |
73 | code table (4.201) | precipitation_type | ptype | 260015 | x | ||
74 | K | k_index | kx | 260121 | x | ||
75 | K | total_totals_index | totalx | 260123 | x |
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2GRIB2 format
3Leaf Area Index (LAI) parameters are based on a monthly climatology. Users will only see monthly variability, but not inter-annual variability.
(stream=oper/enda/mnth/moda/edmm/edmo, levtype=sfc)
count | name | units | Variable name in CDS | shortName | paramId | an | fc |
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1 | s | large_scale_precipitation_fraction | lspf | 50 | x | ||
2 | J m**-2 | downward_uv_radiation_at_the_surface | uvb | 57 | x | ||
3 | J m**-2 | boundary_layer_dissipation | bld | 145 | x | ||
4 | J m**-2 | surface_sensible_heat_flux | sshf | 146 | x | ||
5 | J m**-2 | surface_latent_heat_flux | slhf | 147 | x | ||
6 | J m**-2 | surface_solar_radiation_downwards | ssrd | 169 | x | ||
7 | J m**-2 | surface_thermal_radiation_downwards | strd | 175 | x | ||
8 | J m**-2 | surface_net_solar_radiation | ssr | 176 | x | ||
9 | J m**-2 | surface_net_thermal_radiation | str | 177 | x | ||
10 | J m**-2 | top_net_solar_radiation | tsr | 178 | x | ||
11 | J m**-2 | top_net_thermal_radiation | ttr | 179 | x | ||
12 | N m**-2 s | eastward_turbulent_surface_stress | ewss | 180 | x | ||
13 | N m**-2 s | northward_turbulent_surface_stress | nsss | 181 | x | ||
14 | N m**-2 s | eastward_gravity_wave_surface_stress | lgws | 195 | x | ||
15 | N m**-2 s | northward_gravity_wave_surface_stress | mgws | 196 | x | ||
16 | J m**-2 | gravity_wave_dissipation | gwd | 197 | x | ||
17 | J m**-2 | top_net_solar_radiation_clear_sky | tsrc | 208 | x | ||
18 | J m**-2 | top_net_thermal_radiation_clear_sky | ttrc | 209 | x | ||
19 | J m**-2 | surface_net_solar_radiation_clear_sky | ssrc | 210 | x | ||
20 | J m**-2 | surface_net_thermal_radiation_clear_sky | strc | 211 | x | ||
21 | J m**-2 | toa_incident_solar_radiation | tisr | 212 | x | ||
22 | kg m**-2 | vertically_integrated_moisture_divergence | vimd | 213 | x | ||
23 | J m**-2 | total_sky_direct_solar_radiation_at_surface | fdir | 228021 | x | ||
24 | J m**-2 | clear_sky_direct_solar_radiation_at_surface | cdir | 228022 | x | ||
25 | J m**-2 | surface_solar_radiation_downward_clear_sky | ssrdc | 228129 | x | ||
26 | J m**-2 | surface_thermal_radiation_downward_clear_sky | strdc | 228130 | x | ||
27 | m | surface_runoff | sro | 8 | x | ||
28 | m | sub_surface_runoff | ssro | 9 | x | ||
29 | m of water equivalent | snow_evaporation | es | 44 | x | ||
30 | m of water equivalent | snowmelt | smlt | 45 | x | ||
31 | m | large_scale_precipitation | lsp | 142 | x | ||
32 | m | convective_precipitation | cp | 143 | x | ||
33 | m of water equivalent | snowfall | sf | 144 | x | ||
34 | m of water equivalent | evaporation | e | 182 | x | ||
35 | m | runoff | ro | 205 | x | ||
36 | m | total_precipitation | tp | 228 | x | ||
37 | m of water equivalent | convective_snowfall | csf | 239 | x | ||
38 | m of water equivalent | large_scale_snowfall | lsf | 240 | x | ||
39 | m | potential_evaporation | pev | 228251 | x |
The accumulations in monthly means of daily means (stream=moda/edmo), see monthly means, have been scaled to have units that include "per day", so for accumulations in these streams:
(stream=oper/enda/mnth/moda/edmm/edmo, levtype=sfc)
count | name | units | Variable name in CDS | shortName | paramId | an | fc |
---|---|---|---|---|---|---|---|
1 | kg m**-2 s**-1 | mean_surface_runoff_rate | msror | 235020 | x | ||
2 | kg m**-2 s**-1 | mean_sub_surface_runoff_rate | mssror | 235021 | x | ||
3 | kg m**-2 s**-1 | mean_snow_evaporation_rate | mser | 235023 | x | ||
4 | kg m**-2 s**-1 | mean_snowmelt_rate | msmr | 235024 | x | ||
5 | Proportion | mean_large_scale_precipitation_fraction | mlspf | 235026 | x | ||
6 | W m**-2 | mean_surface_downward_uv_radiation_flux | msdwuvrf | 235027 | x | ||
7 | kg m**-2 s**-1 | mean_large_scale_precipitation_rate | mlspr | 235029 | x | ||
8 | kg m**-2 s**-1 | mean_convective_precipitation_rate | mcpr | 235030 | x | ||
9 | kg m**-2 s**-1 | mean_snowfall_rate | msr | 235031 | x | ||
10 | W m**-2 | mean_boundary_layer_dissipation | mbld | 235032 | x | ||
11 | W m**-2 | mean_surface_sensible_heat_flux | msshf | 235033 | x | ||
12 | W m**-2 | mean_surface_latent_heat_flux | mslhf | 235034 | x | ||
13 | W m**-2 | mean_surface_downward_short_wave_radiation_flux | msdwswrf | 235035 | x | ||
14 | W m**-2 | mean_surface_downward_long_wave_radiation_flux | msdwlwrf | 235036 | x | ||
15 | W m**-2 | mean_surface_net_short_wave_radiation_flux | msnswrf | 235037 | x | ||
16 | W m**-2 | mean_surface_net_long_wave_radiation_flux | msnlwrf | 235038 | x | ||
17 | W m**-2 | mean_top_net_short_wave_radiation_flux | mtnswrf | 235039 | x | ||
18 | W m**-2 | mean_top_net_long_wave_radiation_flux | mtnlwrf | 235040 | x | ||
19 | N m**-2 | mean_eastward_turbulent_surface_stress | metss | 235041 | x | ||
20 | N m**-2 | mean_northward_turbulent_surface_stress | mntss | 235042 | x | ||
21 | kg m**-2 s**-1 | mean_evaporation_rate | mer | 235043 | x | ||
22 | N m**-2 | mean_eastward_gravity_wave_surface_stress | megwss | 235045 | x | ||
23 | N m**-2 | mean_northward_gravity_wave_surface_stress | mngwss | 235046 | x | ||
24 | W m**-2 | mean_gravity_wave_dissipation | mgwd | 235047 | x | ||
25 | kg m**-2 s**-1 | mean_runoff_rate | mror | 235048 | x | ||
26 | W m**-2 | mean_top_net_short_wave_radiation_flux_clear_sky | mtnswrfcs | 235049 | x | ||
27 | W m**-2 | mean_top_net_long_wave_radiation_flux_clear_sky | mtnlwrfcs | 235050 | x | ||
28 | W m**-2 | mean_surface_net_short_wave_radiation_flux_clear_sky | msnswrfcs | 235051 | x | ||
29 | W m**-2 | mean_surface_net_long_wave_radiation_flux_clear_sky | msnlwrfcs | 235052 | x | ||
30 | W m**-2 | mean_top_downward_short_wave_radiation_flux | mtdwswrf | 235053 | x | ||
31 | kg m**-2 s**-1 | mean_vertically_integrated_moisture_divergence | mvimd | 235054 | x | ||
32 | kg m**-2 s**-1 | mean_total_precipitation_rate | mtpr | 235055 | x | ||
33 | kg m**-2 s**-1 | mean_convective_snowfall_rate | mcsr | 235056 | x | ||
34 | kg m**-2 s**-1 | mean_large_scale_snowfall_rate | mlssr | 235057 | x | ||
35 | W m**-2 | mean_surface_direct_short_wave_radiation_flux | msdrswrf | 235058 | x | ||
36 | W m**-2 | mean_surface_direct_short_wave_radiation_flux_clear_sky | msdrswrfcs | 235059 | x | ||
37 | W m**-2 | mean_surface_downward_short_wave_radiation_flux_clear_sky | msdwswrfcs | 235068 | x | ||
38 | W m**-2 | mean_surface_downward_long_wave_radiation_flux_clear_sky | msdwlwrfcs | 235069 | x | ||
39 | kg m**-2 s**-1 | mean_potential_evaporation_rate | mper | 235070 | x |
The mean rates/fluxes in Table 4 provide similar information to the accumulations in Table 3, except they are expressed as temporal averages, and so have units of "per second". The mean rate hydrological parameters have units of "kg m-2 s-1" and so they can be multiplied by 86400 seconds (24 hours) to convert to kg m-2 day-1 or mm day-1.
(stream=oper/enda, levtype=sfc)
count | name | units | Variable name in CDS | shortName | paramId | an | fc |
---|---|---|---|---|---|---|---|
1 | m s**-1 | 10m_wind_gust_since_previous_post_processing | 10fg | 49 | x | ||
2 | Maximum temperature at 2 metres since previous post-processing | K | maximum_2m_temperature_since_previous_post_processing | mx2t | 201 | x | |
3 | Minimum temperature at 2 metres since previous post-processing | K | minimum_2m_temperature_since_previous_post_processing | mn2t | 202 | x | |
4 | Maximum total precipitation rate since previous post-processing | kg m**-2 s**-1 | maximum_total_precipitation_rate_since_previous_post_processing | mxtpr | 228226 | x | |
5 | Minimum total precipitation rate since previous post-processing | kg m**-2 s**-1 | minimum_total_precipitation_rate_since_previous_post_processing | mntpr | 228227 | x |
(stream=oper/enda/mnth/moda/edmm/edmo - vertical integrals not available for type=em/es, levtype=sfc
count | name | units | Variable name in CDS | shortName | paramId | an | fc |
---|---|---|---|---|---|---|---|
1 | kg m**-2 | vertical_integral_of_mass_of_atmosphere | vima | 162053 | x | x | |
2 | K kg m**-2 | vertical_integral_of_temperature | vit | 162054 | x | x | |
3 | J m**-2 | vertical_integral_of_kinetic_energy | vike | 162059 | x | x | |
4 | J m**-2 | vertical_integral_of_thermal_energy | vithe | 162060 | x | x | |
5 | J m**-2 | vertical_integral_of_potential_and_internal_energy | vipie | 162061 | x | x | |
6 | J m**-2 | vertical_integral_of_potential_internal_and_latent_energy | vipile | 162062 | x | x | |
7 | J m**-2 | vertical_integral_of_total_energy | vitoe | 162063 | x | x | |
8 | W m**-2 | vertical_integral_of_energy_conversion | viec | 162064 | x | x | |
9 | kg m**-1 s**-1 | vertical_integral_of_eastward_mass_flux | vimae | 162065 | x | x | |
10 | kg m**-1 s**-1 | vertical_integral_of_northward_mass_flux | viman | 162066 | x | x | |
11 | W m**-1 | vertical_integral_of_eastward_kinetic_energy_flux | vikee | 162067 | x | x | |
12 | W m**-1 | vertical_integral_of_northward_kinetic_energy_flux | viken | 162068 | x | x | |
13 | W m**-1 | vertical_integral_of_eastward_heat_flux | vithee | 162069 | x | x | |
14 | W m**-1 | vertical_integral_of_northward_heat_flux | vithen | 162070 | x | x | |
15 | kg m**-1 s**-1 | vertical_integral_of_eastward_water_vapour_flux | viwve | 162071 | x | x | |
16 | kg m**-1 s**-1 | vertical_integral_of_northward_water_vapour_flux | viwvn | 162072 | x | x | |
17 | W m**-1 | vertical_integral_of_eastward_geopotential_flux | vige | 162073 | x | x | |
18 | W m**-1 | vertical_integral_of_northward_geopotential_flux | vign | 162074 | x | x | |
19 | W m**-1 | vertical_integral_of_eastward_total_energy_flux | vitoee | 162075 | x | x | |
20 | W m**-1 | vertical_integral_of_northward_total_energy_flux | vitoen | 162076 | x | x | |
21 | kg m**-1 s**-1 | vertical_integral_of_eastward_ozone_flux | vioze | 162077 | x | x | |
22 | kg m**-1 s**-1 | vertical_integral_of_northward_ozone_flux | viozn | 162078 | x | x | |
23 | kg m**-2 s**-1 | vertical_integral_of_divergence_of_cloud_liquid_water_flux | vilwd | 162079 | x | x | |
24 | kg m**-2 s**-1 | vertical_integral_of_divergence_of_cloud_frozen_water_flux | viiwd | 162080 | x | x | |
25 | kg m**-2 s**-1 | vertical_integral_of_divergence_of_mass_flux | vimad | 162081 | x | x | |
26 | W m**-2 | vertical_integral_of_divergence_of_kinetic_energy_flux | viked | 162082 | x | x | |
27 | W m**-2 | vertical_integral_of_divergence_of_thermal_energy_flux | vithed | 162083 | x | x | |
28 | kg m**-2 s**-1 | vertical_integral_of_divergence_of_moisture_flux | viwvd | 162084 | x | x | |
29 | W m**-2 | vertical_integral_of_divergence_of_geopotential_flux | vigd | 162085 | x | x | |
30 | W m**-2 | vertical_integral_of_divergence_of_total_energy_flux | vitoed | 162086 | x | x | |
31 | kg m**-2 s**-1 | vertical_integral_of_divergence_of_ozone_flux | viozd | 162087 | x | x | |
32 | kg m**-1 s**-1 | vertical_integral_of_eastward_cloud_liquid_water_flux | vilwe | 162088 | x | x | |
33 | kg m**-1 s**-1 | vertical_integral_of_northward_cloud_liquid_water_flux | vilwn | 162089 | x | x | |
34 | kg m**-1 s**-1 | vertical_integral_of_eastward_cloud_frozen_water_flux | viiwe | 162090 | x | x | |
35 | kg m**-1 s**-1 | vertical_integral_of_northward_cloud_frozen_water_flux | viiwn | 162091 | x | x | |
36 | kg m**-2 s**-1 | vertical_integral_of_mass_tendency | vimat | 162092 | x | ||
37 | kg m**-2 | total_column_cloud_liquid_water | tclw | 78 | x | x | |
38 | kg m**-2 | total_column_cloud_ice_water | tciw | 79 | x | x | |
39 | kg m**-2 | total_column_supercooled_liquid_water | tcslw | 228088 | x | ||
40 | kg m**-2 | total_column_rain_water | tcrw | 228089 | x | x | |
41 | kg m**-2 | total_column_snow_water | tcsw | 228090 | x | x | |
42 | kg m**-2 | total_column_water | tcw | 136 | x | x | |
43 | kg m**-2 | total_column_water_vapour | tcwv | 137 | x | x | |
44 | kg m**-2 | total_column_ozone | tco3 | 206 | x | x |
(stream=wave/ewda/wamo/wamd/ewmm/ewmo)
count | name | units | Variable name in CDS | shortName | paramId | an | fc | |
---|---|---|---|---|---|---|---|---|
1 | m | significant_wave_height_of_first_swell_partition | swh1 | 140121 | x | x | ||
2 | degrees | mean_wave_direction_of_first_swell_partition | mwd1 | 140122 | x | x | ||
3 | s | mean_wave_period_of_first_swell_partition | mwp1 | 140123 | x | x | ||
4 | m | significant_wave_height_of_second_swell_partition | swh2 | 140124 | x | x | ||
5 | degrees | mean_wave_period_of_second_swell_partition | mwd2 | 140125 | x | x | ||
6 | s | mean_wave_period_of_second_swell_partition | mwp2 | 140126 | x | x | ||
7 | m | significant_wave_height_of_third_swell_partition | swh3 | 140127 | x | x | ||
8 | degrees | mean_wave_direction_of_third_swell_partition | mwd3 | 140128 | x | x | ||
9 | s | mean_wave_period_of_third_swell_partition | mwp3 | 140129 | x | x | ||
10 | dimensionless | wave_spectral_skewness | wss | 140207 | x | x | ||
11 | m s**-1 | free_convective_velocity_over_the_oceans | wstar | 140208 | x | x | ||
12 | kg m**-3 | air_density_over_the_oceans | rhoao | 140209 | x | x | ||
13 | dimensionless | normalized_energy_flux_into_waves | phiaw | 140211 | x | x | ||
14 | dimensionless | normalized_energy_flux_into_ocean | phioc | 140212 | x | x | ||
15 | dimensionless | normalized_stress_into_ocean | tauoc | 140214 | x | x | ||
16 | m s**-1 | u_component_stokes_drift | ust | 140215 | x | x | ||
17 | m s**-1 | v_component_stokes_drift | vst | 140216 | x | x | ||
18 | s | period_corresponding_to_maximum_individual_wave_height | tmax | 140217 | x | x | ||
19 | m | maximum_individual_wave_height | hmax | 140218 | x | x | ||
20 | m | model_bathymetry | wmb | 140219 | x | x | ||
21 | s | mean_wave_period_based_on_first_moment | mp1 | 140220 | x | x | ||
22 | s | mean_zero_crossing_wave_period | mp2 | 140221 | x | x | ||
23 | dimensionless | wave_spectral_directional_width | wdw | 140222 | x | x | ||
24 | s | mean_wave_period_based_on_first_moment_for_wind_waves | p1ww | 140223 | x | x | ||
25 | s | mean_wave_period_based_on_second_moment_for_wind_waves | p2ww | 140224 | x | x | ||
26 | dimensionless | wave_spectral_directional_width_for_wind_waves | dwww | 140225 | x | x | ||
27 | s | mean_wave_period_based_on_first_moment_for_swell | p1ps | 140226 | x | x | ||
28 | s | mean_wave_period_based_on_second_moment_for_wind_waves | p2ps | 140227 | x | x | ||
29 | dimensionless | wave_spectral_directional_width_for_swell | dwps | 140228 | x | x | ||
30 | m | significant_height_of_combined_wind_waves_and_swell | swh | 140229 | x | x | ||
31 | degrees | mean_wave_direction | mwd | 140230 | x | x | ||
32 | s | peak_wave_period | pp1d | 140231 | x | x | ||
33 | s | mean_wave_period | mwp | 140232 | x | x | ||
34 | dimensionless | coefficient_of_drag_with_waves | cdww | 140233 | x | x | ||
35 | m | significant_height_of_wind_waves | shww | 140234 | x | x | ||
36 | degrees | mean_direction_of_wind_waves | mdww | 140235 | x | x | ||
37 | s | mean_period_of_wind_waves | mpww | 140236 | x | x | ||
38 | m | significant_height_of_total_swell | shts | 140237 | x | x | ||
39 | degrees | mean_direction_of_total_swell | mdts | 140238 | x | x | ||
40 | s | mean_period_of_total_swell | mpts | 140239 | x | x | ||
41 | dimensionless | mean_square_slope_of_waves | msqs | 140244 | x | x | ||
42 |
| m s**-1 | ocean_surface_stress_equivalent_10m_neutral_wind_speed | wind | 140245 | x | x | |
43 | degrees | ocean_surface_stress_equivalent_10m_neutral_wind_direction | dwi | 140249 | x | x | ||
44 | dimensionless | wave_spectral_kurtosis | wsk | 140252 | x | x | ||
45 | dimensionless | benjamin_feir_index | bfi | 140253 | x | x | ||
46 | dimensionless | wave_spectral_peakedness | wsp | 140254 | x | x | ||
47 | m | Not available from the CDS disks | awh | 140246 | x | |||
48 | m | Not available from the CDS disks | acwh | 140247 | x | |||
49 | ~ | Not available from the CDS disks | arrc | 140248 | x | |||
50 | m**2 s radian**-1 | Not available from the CDS disks | 2dfd | 140251 | x |
1for 30 frequencies and 24 directions
(stream=mnth/moda/edmm/edmo, levtype=sfc or wamo/wamd/ewmm/ewmo)
count | name | units | Variable name in CDS | shortName | paramId | an | fc |
---|---|---|---|---|---|---|---|
1 | (0 - 1) | uv_visible_albedo_for_direct_radiation | aluvp | 15 | x | no mean | |
2 | (0 - 1) | uv_visible_albedo_for_diffuse_radiation | aluvd | 16 | x | no mean | |
3 | (0 - 1) | near_ir_albedo_for_direct_radiation | alnip | 17 | x | no mean | |
4 | (0 - 1) | near_ir_albedo_for_diffuse_radiation | alnid | 18 | x | no mean | |
5 | N m**-2 s | magnitude of turbulent surface stress | magss | 48 | x | ||
6 | Mean magnitude of turbulent surface stress2 | N m**-2 | mean magnitude of turbulent surface stress | mmtss | 235025 | x | |
7 | m s**-1 | 10m_wind_gust_since_previous_post_processing | 10fg | 49 | no mean | ||
8 | Maximum temperature at 2 metres since previous post-processing | K | maximum_2m_temperature_since_previous_post_processing | mx2t | 201 | no mean | |
9 | Minimum temperature at 2 metres since previous post-processing | K | minimum_2m_temperature_since_previous_post_processing | mn2t | 202 | no mean | |
10 | m s**-1 | 10m wind speed | 10si | 207 | x | x | |
11 | Maximum total precipitation rate since previous post-processing | kg m**-2 s**-1 | maximum_total_precipitation_rate_since_previous_post_processing | mxtpr | 228226 | no mean | |
12 | Minimum total precipitation rate since previous post-processing | kg m**-2 s**-1 | minimum_total_precipitation_rate_since_previous_post_processing | mntpr | 228227 | no mean | |
13 | m | Not available from the CDS disks | awh | 140246 | no mean | ||
14 | m | Not available from the CDS disks | acwh | 140247 | no mean | ||
15 | ~ | Not available from the CDS disks | arrc | 140248 | no mean | ||
16 | m**2 s radian**-1 | Not available from the CDS disks | 2dfd | 140251 | no mean |
1Accumulated parameter
2Mean rate/flux parameter
3Instantaneous parameter
(stream=oper/enda/mnth/moda/edmm/edmo, levtype=pl)
count | name | units | Variable name in CDS | shortName | paramId | an | fc |
---|---|---|---|---|---|---|---|
1 | K m**2 kg**-1 s**-1 | potential_vorticity | pv | 60 | x | x | |
2 | kg kg**-1 | specific_rain_water_content | crwc | 75 | x | x | |
3 | kg kg**-1 | specific_snow_water_content | cswc | 76 | x | x | |
4 | m**2 s**-2 | geopotential | z | 129 | x | x | |
5 | K | temperature | t | 130 | x | x | |
6 | m s**-1 | u_component_of_wind | u | 131 | x | x | |
7 | m s**-1 | v_component_of_wind | v | 132 | x | x | |
8 | kg kg**-1 | specific_humidity | q | 133 | x | x | |
9 | Pa s**-1 | vertical_velocity | w | 135 | x | x | |
10 | s**-1 | vorticity | vo | 138 | x | x | |
11 | s**-1 | divergence | d | 155 | x | x | |
12 | % | relative_humidity | r | 157 | x | x | |
13 | kg kg**-1 | ozone_mass_mixing_ratio | o3 | 203 | x | x | |
14 | kg kg**-1 | specific_cloud_liquid_water_content | clwc | 246 | x | x | |
15 | kg kg**-1 | specific_cloud_ice_water_content | ciwc | 247 | x | x | |
16 | (0 - 1) | fraction_of_cloud_cover | cc | 248 | x | x |
(not available from the CDS disks)
(stream=oper/enda/mnth/moda/edmm/edmo, levtype=pt)
count | name | units | shortName | paramId | an | fc |
---|---|---|---|---|---|---|
1 | m**2 s**-2 | mont | 53 | x | ||
2 | Pa | pres | 54 | x | ||
3 | K m**2 kg**-1 s**-1 | pv | 60 | x | ||
4 | m s**-1 | u | 131 | x | ||
5 | m s**-1 | v | 132 | x | ||
6 | kg kg**-1 | q | 133 | x | ||
7 | s**-1 | vo | 138 | x | ||
8 | s**-1 | d | 155 | x | ||
9 | kg kg**-1 | o3 | 203 | x |
(not available from the CDS disks)
(stream=oper/enda/mnth/moda/edmm/edmo, levtype=pv)
count | name | units | shortName | paramId | an | fc |
---|---|---|---|---|---|---|
1 | K | pt | 3 | x | ||
2 | Pa | pres | 54 | x | ||
3 | m**2 s**-2 | z | 129 | x | ||
4 | m s**-1 | u | 131 | x | ||
5 | m s**-1 | v | 132 | x | ||
6 | kg kg**-1 | q | 133 | x | ||
7 | kg kg**-1 | o3 | 203 | x |
(GRIB2 format)
(not available from the CDS disks)
(stream=oper/enda/mnth/moda/edmm/edmo, levtype=ml)
count | name | units | shortName | paramId | an | fc |
---|---|---|---|---|---|---|
1 | kg kg**-1 | crwc | 75 | x | x | |
2 | kg kg**-1 | cswc | 76 | x | x | |
3 | s**-1 | etadot | 77 | x | x | |
4 | m**2 s**-2 | z | 129 | x | x | |
5 | K | t | 130 | x | x | |
6 | m s**-1 | u | 131 | x | x | |
7 | m s**-1 | v | 132 | x | x | |
8 | kg kg**-1 | q | 133 | x | x | |
9 | Pa s**-1 | w | 135 | x | x | |
10 | s**-1 | vo | 138 | x | x | |
11 | ~ | lnsp | 152 | x | x | |
12 | s**-1 | d | 155 | x | x | |
13 | kg kg**-1 | o3 | 203 | x | x | |
14 | kg kg**-1 | clwc | 246 | x | x | |
15 | kg kg**-1 | ciwc | 247 | x | x | |
16 | (0 - 1) | cc | 248 | x | x |
1Only archived on level=1.
(GRIB2 format)
(not available from the CDS disks)
(stream=oper/enda/mnth/moda/edmm/edmo, levtype=ml)
count | name | units | shortName | paramId | an | fc |
---|---|---|---|---|---|---|
1 | Mean temperature tendency due to short-wave radiation | K s**-1 | mttswr | 235001 | x | |
2 | Mean temperature tendency due to long-wave radiation | K s**-1 | mttlwr | 235002 | x | |
3 | Mean temperature tendency due to short-wave radiation, clear sky | K s**-1 | mttswrcs | 235003 | x | |
4 | Mean temperature tendency due to long-wave radiation, clear sky | K s**-1 | mttlwrcs | 235004 | x | |
5 | Mean temperature tendency due to parametrisations | K s**-1 | mttpm | 235005 | x | |
6 | Mean specific humidity tendency due to parametrisations | kg kg**-1 s**-1 | mqtpm | 235006 | x | |
7 | Mean eastward wind tendency due to parametrisations | m s**-2 | mutpm | 235007 | x | |
8 | Mean northward wind tendency due to parametrisations | m s**-2 | mvtpm | 235008 | x | |
9 | Mean updraught mass flux1 | kg m**-2 s**-1 | mumf | 235009 | x | |
10 | Mean downdraught mass flux1 | kg m**-2 s**-1 | mdmf | 235010 | x | |
11 | Mean updraught detrainment rate | kg m**-3 s**-1 | mudr | 235011 | x | |
12 | Mean downdraught detrainment rate | kg m**-3 s**-1 | mddr | 235012 | x | |
13 | Mean total precipitation flux1 | kg m**-2 s**-1 | mtpf | 235013 | x | |
14 | Mean turbulent diffusion coefficient for heat1 | m**2 s**-1 | mtdch | 235014 | x |
1These parameters provide data for the model half levels - the interfaces of the model layers.
The observations (satellite and in-situ) used as input to ERA5 are listed below. For more information on the observational input to ERA5, including dates when particular sensors or observation types were used, please see Section 5 in the journal article, The ERA5 global reanalysis.
Sensor | Satellite | Satellite agency | Data provider+ | Measurement (sensitivities exploited in ERA5 / variables analysed) |
---|---|---|---|---|
Satellite radiances (infrared and microwave) | ||||
AIRS | AQUA | NASA | NOAA | BT (T, humidity and ozone) |
AMSR-2 | GCOM-W1* | JAXA | BT (column water vapour, cloud liquid water, precipitation and ocean surface wind speed) | |
AMSRE | AQUA* | JAXA | BT (column water vapour, cloud liquid water, precipitation and ocean surface wind speed) | |
AMSUA | NOAA-15/16/17/18/19, AQUA, METOP-A/B | NOAA,ESA,EUMETSAT | BT (T) | |
AMSUB | NOAA-15/16/17 | NOAA | BT (humidity) | |
ATMS | NPP | NOAA | BT (T and humidity) | |
CRIS | NPP | NOAA | BT (T, humidity and ozone) | |
HIRS | TIROS-N, NOAA-6 /7/8/9/11/14 | NOAA | BT (T, humidity and ozone) | |
IASI | METOP-A/B | EUMETSAT/ESA | EUMETSAT | BT (T, humidity and ozone) |
GMI | GPM | NASA/JAXA | BT (humidity, column water vapour, cloud liquid water, precipitation, ocean surface wind speed) | |
MHS | NOAA-18/19, METOP-A/B | NOAA, EUMETSAT/ESA | BT (humidity and precipitation) | |
MSU | TIROS-N, NOAA-6 to 12, NOAA-14 | BT (T) | ||
MWHS | FY-3-A/B | NRSCC | BT (humidity) | |
MWHS2 | FY-3-C | CMA | BT (T, humidity and precipitation) | |
MWTS | FY-3A/B | NRSCC | BT (T) | |
MWTS2 | FY-3C | CMA | BT (T) | |
SSM/I | DMSP-08*/10*/11*/13*/14*/15* | US Navy | NOAA,CMSAF* | BT (column water vapour, cloud liquid water, precipitation and ocean surface wind speed) |
SSMIS | DMSP-16/17/18 | US Navy | NOAA | BT (T, humidity, column water vapour, cloud liquid water, precipitation and ocean surface wind speed) |
SSU | TIROS-N, NOAA-6/7/8/9/11/14 | NOAA | BT (T) | |
TMI | TRMM | NASA/JAXA | BT (column water vapour, cloud liquid water, precipitation, ocean surface wind speed) | |
MVIRI | METEOSAT 5/7 | EUMETSAT/ESA | EUMETSAT | BT (water vapour, surface/cloud top T) |
SEVIRI | METEOSAT-8*/9*/10 | EUMETSAT/ESA | EUMETSAT | BT (water vapour, surface/cloud top T) |
GOES IMAGER | GOES-8/9/10/11/12/13/15 | NOAA | CIMMS,NESDIS | BT (water vapour, surface/cloud top T) |
MTSAT IMAGER | MTSAT-1R/MTSAT-2 | JMA | BT (water vapour, surface/cloud top T) | |
AHI | Himawari-8 | JMA | BT (water vapour, surface/cloud top T) | |
Satellite retrievals from radiance data | ||||
MVIRI | METEOSAT-2*/3*/4*/5*/7* | EUMETSAT/ESA | EUMETSAT | wind vector |
SEVIRI | METEOSAT-8*/9*/10 | EUMETSAT/ESA | EUMETSAT | wind vector |
GOES IMAGER | GOES-4-6/8*/9*/10*/11*/12*/13*/15* | NOAA | CIMMS*,NESDIS | wind vector |
GMS IMAGER | GMS-1*/2/3*/4*/5* | JMA | wind vector | |
MTSAT IMAGER | MTSAT-1R*/MTSAT2 | JMA | wind vector | |
AHI | Himawari-8 | JMA | JMA | wind vector |
AVHRR | NOAA-7 /9/10/11/12/14 to 18, METOP-A | NOAA | CIMMS,EUMETSAT | wind vector |
MODIS | AQUA/TERRA | NASA | NESDIS,CIMMS | wind vector |
GOME | ERS-2* | ESA | Ozone | |
GOME-2 | METOP*-A/B | ESA/EUMETSAT | Ozone | |
MIPAS | ENVISAT* | ESA | Ozone | |
MLS | EOS-AURA* | NASA | Ozone | |
OMI | EOS-AURA* | NASA | Ozone | |
SBUV,SBUV-2 | NIMBUS-7*,NOAA*9/11/14/16/17/18/19 | NOAA | NASA | Ozone |
SCIAMACHY | ENVISAT* | ESA | Ozone | |
TOMS | NIMBUS-7*,METEOR-3-5,ADEOS-1*,EARTH PROBE | NASA | Ozone | |
Satellite GPS-Radio Occultation data | ||||
BlackJack | CHAMP,GRACE*-A/B,SAC-C* | DLR,NASA/DLR,NASA/COMAE | GFZ,UCAR* | Bending angle |
GRAS | METOP-A/B | EUMETSAT/ESA | EUMETSAT | Bending angle |
IGOR | TerraSAR-X*, TanDEM-X, COSMIC*-1 to 6 | NSPO/NOAA | GFZ,UCAR* | Bending angle |
Satellite scatterometer data | ||||
AMI | ERS-1,ERS-2 | ESA | Backscatter sigma0, soil moisture | |
ASCAT | METOP-A/B* | EUMETSAT/ESA | EUMETSAT/TU Wien | Backscatter sigma0, soil moisture |
OSCAT | OCEANSAT-2 | ISRO | KNMI | Backscatter sigma0, vector wind |
SEAWINDS | QUIKSCAT | NASA | NASA | Backscatter sigma0 |
Satellite Altimeter data | ||||
RA | ERS-1*/2* | ESA | Wave Height | |
RA-2 | ENVISAT* | ESA | Wave Height | |
Poseidon-2 | JASON-1* | CNES/NASA | CNES | Wave Height |
Poseidon-3 | JASON-2 | CNES/NOAA/NASA/EUMETSAT | NOAA/EUMETSAT | Wave Height |
SIRAL | CRYOSAT-2 | ESA | Wave Height | |
AltiKa | SARAL | CNES/ISRO | EUMETSAT | Wave Height |
* reprocessed dataset
+ when different than the satellite agency
Dataset name | Observation type | Measurement |
---|---|---|
SYNOP | Land station | Surface Pressure, Temperature, wind, humidity |
METAR | Land station | Surface Pressure, Temperature, wind,humidity |
DRIBU/DRIBU-BATHY/DRIBU-TESAC/BUFR Drifting Buoy | Drifting buoys | 10m-wind, Surface Pressure |
BUFR Moored Buoy | Moored buoys | 10m-wind, Surface Pressure |
SHIP | ship station | Surface Pressure, Temperature, wind, humidity |
Land/ship PILOT | Radiosondes | wind profiles |
American Wind Profiler | Radar | wind profiles |
European Wind Profiler | Radar | wind profiles |
Japanese Wind Profiler | Radar | wind profiles |
TEMP SHIP | Radiosondes | Temperature, wind, humidity profiles |
DROP Sonde | Aircraft-sondes | Temperature, wind profiles |
Land/Mobile TEMP | Radiosondes | Temperature, wind, humidity profiles |
AIREP | Aircraft data | Temperature, wind profiles |
AMDAR | Aircraft data | Temperature, wind profiles |
ACARS | Aircraft data | Temperature, wind profiles, humidity |
WIGOS AMDAR | Aircraft data | Temperature, wind profiles |
Ground based radar | Radar precipitation composites | Rain rates |
Dataset name | Observation type | Measurement |
---|---|---|
SYNOP | Land station | Snow depth |
Additional national reports | Land station | Snow depth |
NOAA/NESDIS IMS | Merged satellite | Snow cover (NH only) |
The following advice is intended to help users understand particular features of the ERA5 data:
In the ECMWF data archive (MARS), ERA5 data is archived on various native grids. For the CDS disks, ERA5 data have been interpolated and are stored on regular latitude/longitude grids. For more information, see ERA5: data documentation#Spatialgrid. Storing the data on these different grids can cause incompatibilities, particularly when comparing native spherical harmonic, pressure level, MARS data with CDS disk data on a third, coarse grid. Native spherical harmonic, pressure level parameters are comprised of: Geopotential, Temperature, U component of wind, V component of wind, Vertical velocity, Vorticity, Divergence and Relative humidity. When these parameters are retrieved from MARS and a coarse output grid is specified, the default behaviour is that the spherical harmonics are truncated to prevent aliasing on the output grid. The coarser the output grid, the more severe the truncation. This truncation removes the higher wavenumbers, making the data smoother. However, the CDS disk data has been simply interpolated to the third grid, without smoothing. This incompatibility is particularly relevant when comparing ERA5.1 data (which are only available from MARS - see ERA5: data documentation#DataorganisationandhowtodownloadERA5 - and only for 2000-2006) with ERA5 data on the CDS disks. The simplest means of minimising such incompatibilities is to retrieve the MARS data on the same grid as that used to store the ERA5 CDS disk data. |
The land-sea mask in ERA5 is an invariant field. This parameter is the proportion of land, as opposed to ocean or inland waters (lakes, reservoirs, rivers and coastal waters), in a grid box. The ERA5 land-sea mask provided is not suitable for direct use with wave parameters, as the time variability of the sea-ice cover needs to be taken into account and wave parameters are undefined for non-sea points. In order to produce a land-sea mask for use with wave parameters, users need to download the following ERA5 data (for the required period):
and combine these data to produce the land-sea mask (Fig 3). See attached pictures: Fig 1: Model bathymetry Fig 2: Sea-ice cover Fig 3: Combined mask
Please see the Toolbox workflow below to see a possible way to proceed. The results is a carousel of land-sea mask for each time step requested:
|
The following wave parameters are sparse observations, or quantities derived from the observations, that have been interpolated to the wave model grid and contain many missing values:
These parameters are not available from the CDS disks but can be retrieved from MARS using the CDS API. For further guidelines, please see: Altimeter wave height in the Climate Data Store (CDS) |
Near-surface humidity is not archived directly in ERA datasets, but the archive contains near-surface (2m from the surface) temperature (T), dew point temperature (Td), and surface pressure (sp) from which you can calculate specific and relative humidity at 2m.
Relative humidity can be calculate with respect to saturation over water, ice or mixed phase by defining es(T) with respect to saturation over water, ice or mixed phase (water and ice). The usual practice is to define near-surface relative humidity with respect to saturation over water. |
In the ECMWF model (IFS), snow is represented by an additional layer on top of the uppermost soil level. The whole grid box may not be covered in snow. The snow cover gives the fraction of the grid box that is covered in snow. For ERA5, the snow cover (SC) is computed using snow water equivalent (ie parameter SD (141.128)) as follows:
|
The parameter "Forecast albedo" is only for diffuse radiation and assuming a fixed spectrum of downward short-wave radiation at the surface. The true broadband, all-sky, surface albedo can be calculated from accumulated parameters: (SSRD-SSR)/SSRD where SSRD is parameter 169.128 and SSR is 176.128. This true surface albedo cannot be calculated at night when SSRD is zero. For more information, see Radiation quantities in the ECMWF model and MARS. |
Currently, we are aware of these issues with ERA5:
ERA5 suffers from an overly strong equatorial mesospheric jet, particularly in the transition seasons.
From 2000 to 2006, ERA5 has a poor fit to radiosonde temperatures in the stratosphere, with a cold bias in the lower stratosphere. In addition, a warm bias higher up persists for much of the period from 1979. The lower stratospheric cold bias was rectified in a re-run for the years 2000 to 2006, called ERA5.1, see "Resolved issues" below.
The ERA5 analysed and forecast step=0, instantaneous surface stress components and surface roughness and the forecast step=0, friction velocity (friction velocity is not available from the analyses in ERA5) tend to suffer from values that are too low over the oceans. The analysis for such parameters is obtained by running the surface module to connect the surface with the model level analysed variables. However, at that stage, the surface aero-dynamical roughness length scale (z0) over the oceans is not initialised from its actual value but a constant value of 0.0001 is used instead. This initial value of z0 is needed to determine the initial value of u* and the surface stress based on solving for a simple logarithmic wind profile between the surface and the lowest model level. This initial u* is in turn used to determine an updated value of z0 based on the input Charnock parameter and then the value of the exchange coefficients needed to determine the output 10m winds (normal and neutral) and u* (see (3.91) to (3.94) with (3.26) in the IFS documentation). The surface stress is output as initialised. This initial value for z0 is generally too low ( by one order of magnitude or more): Over the oceans, for winds above few m/s, z0 is modelled using the Charnock relation: z0 ~ (alpha/g) u*2 where alpha is the Charnock parameter, g is gravity, and u* is the friction velocity with typical values of alpha ~ 0.018 g=9.81 u*2 = Cd U102 where Cd is the drag coefficient Cd ~ 0.008 + 0.0008 U10 for U10=10m/s => z0 ~ 0.003 As a consequence, the analysed instantaneous surface stress components will tend to be too low and even the updated value of z0 (surface roughness) will also tend to be too low. For forecast, instantaneous surface stress components, surface roughness and friction velocity, the same problem affects step 0. However, this problem will not affect the accumulated surface stress parameters (recall the accumulated parameters are produced by running short range forecasts), because the accumulation starts from the first time step (i.e. at time step 0 all accumulated variables are initialised to 0). This problem can easily be fixed, by using the initial value of Charnock that is available at the initial time. Note, in ERA5 the parameter for surface roughness is called "forecast surface roughness", even when it's analysed. |
ERA5 forecast parameters are missing for the validity times of 1st January 1979 from 00 UTC to 06 UTC. This problem has occurred because the forecast producing these data started from 18 UTC on the last day of 1978. This gap can be filled by using forecast data from the ERA5 back extension (preliminary version), with date=19781231, time=18 and step=6/to/12:
Eventually, the data gap will be filled by the re-run of the ERA5 back extension. |
The ERA5 monthly means are calculated from the hourly (3 hourly for the EDA) data, on the native grid (including spherical harmonics) from the GRIB data, in each production "stream" or experiment. This can give rise to inconsistencies between the hourly (or 3 hourly) data and their monthly mean, particularly in the CDS:
|
ERA5.1 is a re-run of ERA5, for the years 2000 to 2006 only, and was produced to improve upon the cold bias in the lower stratosphere seen in ERA5.
ERA5.1 is a re-run of ERA5 for the years 2000 to 2006 only. ERA5.1 was produced to improve upon the cold bias in the lower stratosphere exhibited by ERA5 during this period. Moreover, ERA5.1 analyses have a better representation of the following features:
The lower and middle troposphere in ERA5.1 are similar to those in ERA5, as is the synoptic evolution in the extratropical stratosphere. For access to ERA5.1 data read Data organisation and how to download ERA5. The dataset is 'reanalysis-era5.1-complete' in the CDS API. |
ERA5.1 CDS: If you retrieved ERA5.1 using the CDS API anytime before 20/05/2020 08:00 UTC, for any stream other than oper (i.e. streams: wave, enda, edmo, ewmo, edmm, ewmm, ewda, moda, wamd, mnth, wamo), you will need to request the data again. Prior to this date, stream oper would be delivered regardless of which stream was requested.
There is a range of user support available for ERA5, including a Knowledge Base (where this article resides), a Forum and a ticketed system for questions - for more information see the C3S Help and Support Page.
For ERA5 data on the "CDS disks"
All users of data on the Climate Data Store (CDS) disks (using either the web interface or the CDS API) must provide clear and visible attribution to the Copernicus programme and are asked to cite and reference the dataset provider:
The 3-steps procedure above is illustrated with this example: Use Case 2: ERA5 hourly data on single levels from 1979 to present
For complete details, please refer to How to acknowledge, cite and reference data published on the Climate Data Store.
For ERA5 data in MARS,
If you have downloaded ERA5 data in MARS, using either the CDS API ('reanalysis-era5-complete'
or 'reanalysis-era5.
1
-complete' or '
) or via authorised direct access to MARS, please contact the C3S Helpdesk at ECMWF.reanalysis-era5-complete-preliminary-back-extension'
Global stratospheric temperature bias and other stratospheric aspects of ERA5 and ERA5.1
Further ERA5 references are available from the ECMWF e-Library.
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. |