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This catalogue entry provides Regional Climate Model (RCM) data on single levels from a number of experiments, models, members, time frequencies and periods computed over several regional domains and in the framework of the Coordinated Regional Climate Downscaling Experiment (CORDEX). The term "single levels" is used to express that the variables are 2D-matrices computed on one vertical level which can be surface (or a level close to the surface) or a dedicated pressure level in the atmosphere. Multiple vertical levels are excluded from this catalogue entry.

High-resolution Regional Climate Models (RCMs) can provide climate change information on regional and local scales in relatively fine detail, which cannot be obtained from coarse scale Global Climate Models (GCMs). This is manifested in better description of small-scale regional climate characteristics and also in more accurate representation of extreme events. Consequently, outputs of such RCMs are indispensable in supporting regional and local climate impact studies and adaptation decisions. RCMs are not independent from the GCMs, since the GCMs provide lateral and lower boundary conditions to the regional models. In that sense RCMs can be viewed as magnifying glasses of the GCMs.

The CORDEX experiments consist of RCM simulations representing different future socio-economic scenarios (forcings), different combinations of GCMs and RCMs and different ensemble members of the same GCM-RCM combinations. This experiment design through the ensemble members allows for studies addressing questions related to the key uncertainties in future climate change. These uncertainties come from differences in the scenarios of future socio-economic development, the imperfection of regional and global models used and the internal (natural) variability of the climate system. This experiment design allows for studies addressing questions related to the key uncertainties in future climate change:

  • what will future climate forcing be?
  • what will be the response of the climate system to changes in forcing?
  • what is the uncertainty related to natural variability of the climate system?

The term "region" in the CDS form refers to the different regional domains:

  • EUR: European domain from 27°N to 72°N and from 22°W to 45°E. The horizontal resolution for this domain is 0.11°x0.11° (EUR-11).
  • MED: Mediterranean domain from 25°N to 52°N and from 21°W to 50°E. The horizontal resolutions for this domain are 0.11°x0.11° (MED-11) and 0.44°x0.44° (MED-44).
  • NAM: North-American domain from 12°N to 59°N and from 171°W to 24°W. The horizontal resolutions for this domain are 0.22°x0.22° (NAM-22) and 0.44°x0.44° (NAM-44).
  • ARC: Arctic domain from 46°N to 90°N and from 180°W  to 180°E. The horizontal resolutions for this domain are 0.22°x0.22° (ARC-22) and 0.44°x0.44° (ARC-44)

Additional details on each CORDEX geographical domain are available at https://cordex.org/domains/.

The term "experiment" in the CDS form refers to three main categories:

  • Evaluation: CORDEX experiment driven by ECMWF ERA-Interim reanalysis for a past period. These experiments can be used to evaluate the quality of the RCMs using perfect boundary conditions as provided by a reanalysis system. The period covered is typically 1980-2010;
  • Historical: CORDEX experiment which covers a period for which modern climate observations exist. Boundary conditions are provided by GCMs. These experiments, that follow the observed changes in climate forcing, show how the RCMs perform for the past climate when forced by GCMs and can be used as a reference period for comparison with scenario runs for the future. The period covered is typically 1950-2005;
  • Scenario: Ensemble of CORDEX climate projection experiments using RCP (Representative Concentration Pathways) forcing scenarios. These scenarios are the RCP 2.6, 4.5 and 8.5 scenarios providing different pathways of the future climate forcing. Boundary conditions are provided by GCMs. The period covered is typically 2006-2100.

In CORDEX, the same experiments were done using different RCMs (labelled as “Regional Climate Model” in the CDS form).

In addition, for each RCM, there is a variety of GCMs, which can be used as lateral boundary conditions. The GCMs used are coming from the CMIP5 (5th phase of the Coupled Model Intercomparison Project) archive. These GCM boundary conditions are labelled as “Global Climate Model” in the form and are also available in the CDS.

Additionally, the uncertainty related to internal variability of the climate system is sampled by running several simulations with the same RCM-GCM combination. On the forms, these are indexed as separate ensemble members (the naming convention for ensemble members is available in the documentation). For each GCM, the same experiment was repeatedly done using slightly different conditions (like initial conditions or different physical parameterisations for instance) producing in that way an ensemble of experiments closely related. More details behind these sequential ensemble numbers will be available in the detailed documentation.

On a general level in the CDS form for the RCM simulations “v” enumerates runs and not model versions. Runs numbers different from “v1” means new simulations relative to the first “v1” one. It might not mean a new version:

  • For the EC-EARTH and HadGEM2-ES forced HIRHAM RCM simulation “v2” is a new simulation where proper GHG concentrations changing with time are used as a contrast to “v1” that erroneously used the constant control level throughout the simulation. Therefore users should use "v2".
  • For NorESM forced HIRAM RCM “v2” run includes also an error in the vertical interpolation when preparing the boundary files also exists. Therefore users should use "v3".
  • For the MOHC-HadGEM2-ES forced RACMO simulation "v2" is a new simulation where a big error in SST-remapping from the HadGEM-grid to the RCM-grid in "v1" was corrected. The erroneous v1-simulation has been unpublished from the ESGF.
  • For the CNRM-CM5 forced runs "v2" is a new simulation replacing the old now with input data taken from pressure levels instead of model levels. The originally provided model level fields from CNRM were wrong.
  • Two MPI-driven scenario runs were rerun in 2016 as there had been problems with a restart file and as there was an error in the snow diagnostics in the original run. The reruns were labelled "v1a".

The data are produced by the participating institutes of the EURO-CORDEX, Med-CORDEX projects and several national contributions to CORDEX.

Recommended search procedure: 

  1. Select the CORDEX region of interest
  2. Select the spatial resolution of interest
  3. Select the CORDEX experiment (e.g., future scenario) of interest
  4. Select the required variable(s) for your analysis.
  5. (Optional) Select the required time period (which depends on the experiment). 
  6. The search interface will adapt the other selection fields according to the available data (e.g., which models provides the variable you want, how many ensemble are available, etc.)
DATA DESCRIPTION
Data typeGridded
Horizontal coverageDepends on the regional domain (grid projection may differ among RCMs)
Horizontal resolution0.11°x0.11°, 0.22°x0.22° or 0.44°x0.44° depending on the region.
Vertical resolutionVariables are provided in one single level (which may differ among variables)
Temporal coverage

evaluation runs are from 1989 to 2008

historical runs are from 1951 to 2005

scenario runs are from 2006 to 2100

Temporal resolution3h, 6h, daily, monthly and seasonal
File formatNetCDF4
ConventionsClimate and Forecast (CF) Metadata Convention v1.6
VersionsLatest version of the data is provided.
Update frequencyRegular quarterly updates


MAIN VARIABLES
NameShort nameUnitsDescription
2m temperaturetasKThe temperature of the air near the surface (or ambient temperature). The data represents the mean over the aggregation period at 2m above the surface.
200hPa temperatureta200KThe temperature of the air at 200hPa. The data represents the mean over the aggregation period at 200hPa above the surface.
Minimum 2m temperature in the last 24 hourstasminKThe minimum temperature of the air near the surface. The data represents the daily minimum over the aggregation period at 2m above the surface.
Maximum 2m temperature in the last 24 hourstasmaxKThe maximum temperature of the air near the surface. The data represents the daily maximum over the aggregation period at 2m above the surface.
Mean precipitation fluxprkg.m-2.s-1The deposition of water to the Earth's surface in the form of rain, snow, ice or hail. The precipitation flux is the mass of water per unit area and time. The data represents the mean over the aggregation period.
2m surface relative humidityhurs%

The relative humidity is the percentage ratio of the water vapour mass to the water vapour mass at the saturation point given the temperature at that location. The data represents the mean of the amount of moisture divided by the maximum amount of moisture that could exist in the air at a specific temperature and location, over the aggregation period at 2m above the surface.

2m surface specific humidityhussDimensionlessThe amount of moisture in the air at 2m above the surface divided by the amount of air plus moisture at that location. The data represents the mean over the aggregation period at 2m above the surface.
Surface pressurepsPa

The air pressure at the lower boundary of the atmosphere. The data represents the mean over the aggregation period.

Mean sea level pressurepslPaThe air pressure at sea level. In regions where the Earth's surface is above sea level the surface pressure is used to compute the air pressure that would exist at sea level directly below given a constant air temperature from the surface to the sea level point. The data represents the mean over the aggregation period.
10m Wind SpeedsfcWindm.s-1The magnitude of the two-dimensional horizontal air velocity. The data represents the mean over the aggregation period at 10m above the surface.
Surface solar radiation downwardsrsdsW.m-2The downward shortwave radiative flux of energy per unit area. The data represents the mean over the aggregation period at the surface.
Surface thermal radiation downwardrldsW.m-2

The downward longwave radiative flux of energy inciding on the surface from the above per unit area. The data represents the mean over the aggregation period.

Surface upwelling shortwave radiationrsusW.m-2

The upward shortwave radiative flux of energy from the surface per unit area. The data represents the mean over the aggregation period at the surface.

Total cloud covercltDimensionlessTotal refers to the whole atmosphere column, as seen from the surface or the top of the atmosphere. Cloud cover refers to fraction of horizontal area occupied by clouds. The data represents the mean over the aggregation period.
500hPa geopotentialzg500mThe gravitational potential energy per unit mass normalized by the standard gravity at 500hPa at the same latitude. The data represents the mean over the aggregation period at 500hPa over the surface.
10m u-component of winduasm.s-1The magnitude of the eastward component of the wind. The data represents the mean over the aggregation period at 10m above the surface.
10m v-component of windvasm.s-1The magnitude of the northward component of the wind. The data represents the mean over the aggregation period at 10m above the surface.
200hPa u-component of the windua200m.s-1

The magnitude of the eastward component of the wind. The data represents the mean over the aggregation period at 200hPa above the surface.

200hPa v-component of the windva200m.s-1The magnitude of the northward component of the wind. The data represents the mean over the aggregation period at 200hPa above the surface.
850hPa U-component of the windua850m.s-1The magnitude of the eastward component of the wind. The data represents the mean over the aggregation period at 850hPa above the surface.
850hPa V-component of the windva850m.s-1The magnitude of the northward component of the wind. The data represents the mean over the aggregation period at 850hPa above the surface.
Total run-off fluxmrrokg.m-2.s-1

The mass of surface and sub-surface liquid water per unit area and time, which drains from land. The data represents the mean over the aggregation period.

Mean evaporation fluxevspsblkg.m-2.s-1

The mass of surface and sub-surface liquid water per unit area ant time, which evaporates from land. The data includes conversion to vapor phase from both the liquid and solid phase, i.e., includes sublimation, and reprends the mean over the aggregation period.

Land area fractionsftlf%The percentage of the surface occupied by land, aka land/sea mask. The data  is time-independent.
OrographyorogmThe surface altitude. The data is time-independent.


Record updated 2020-10-01 10:30:34 UTC

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