ERA5 Wizard
Planning an ERA5 Dataset
Step 1: Station Location
The first section of the Wizard defines the geographic reference point for the ERA5 request.
In the Plan CDS ERA5 data to download window, the station location is displayed through:
- Latitude (Lat),
- Longitude (Lon).
The location can be defined using:
- Pick from map… âž” opens an interactive map window where the user places a pin.
- KML/KMZ… âž” imports a geographic file.
If the file contains a point geometry, that point is used. If it contains a path, the first vertex is adopted as the reference location.
When the map window is used, the selected pin coordinates are returned to the Wizard and displayed in the Lat/Lon fields. These coordinates represent the geographic reference for which the ERA5 dataset will be planned.
At this stage, no spatial interpretation of grid points is performed. The Wizard simply records a geographic location to be used for constructing the subregion request.
The selected location represents a geographic reference point for planning the ERA5 request. The actual spatial interpretation of the dataset will be performed later during the Analyze GRIB phase.
Step 2: Define Subregion
Below the station coordinates, the Wizard displays the automatically generated subregion bounds:
- North (N),
- South (S),
- West (W),
- East (E).
These values define the spatial extent that will be requested from the Copernicus Climate Data Store.
The subregion is generated algorithmically from the selected station location. The bounding box is aligned with the native ERA5 grid resolution (typically 0.25° × 0.25°) in order to ensure consistency with the underlying reanalysis grid.
The subregion is defined in a way that preserves consistency with the native ERA5 grid structure, ensuring that the requested dataset remains coherent with the underlying reanalysis resolution.
The Wizard does not display the ERA5 grid explicitly; however, the resulting subregion is constructed so that it is coherent with the native grid spacing used by ERA5.
The defined subregion will appear in the ERA5 Request Recap and must be used when configuring the request on the Copernicus CDS portal.
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Step 3: Temporal Coverage
The temporal coverage of the ERA5 request is defined in the Wizard through two fields:
- Start year,
- Number of years.
The Start year specifies the first calendar year to be included in the dataset. The Number of years determines how many consecutive years, starting from the selected year, will be requested from the Copernicus Climate Data Store.
The selected period is explicitly summarized in the ERA5 Request Recap window as:
Selected period: YYYY–YYYY (N year[s])
In typical regulatory preprocessing workflows (e.g., preparation of meteorological input for AERMET or CALMET), datasets are often prepared on a full annual basis. The Wizard allows multi-year selections in order to support extended climatological assessments when required.
The temporal definition provided at this stage determines which GRIB messages will be generated by CDS and subsequently imported into WindRose Studio for structural inspection and analysis.
The selected temporal coverage determines which GRIB messages will be generated by the CDS request and subsequently inspected within WindRose Studio.
Step 4: Choose Variables
The Wizard provides predefined ERA5 variable configurations accessible through the Minimal / Advanced / Pro selection.
Each preset recommends a coherent group of single-level ERA5 variables according to the intended analytical purpose.
Minimal:
- 10m u-component of wind,
- 10m v-component of wind.
These variables allow reconstruction of wind speed and wind direction, forming the basis for wind roses, frequency tables and regulatory preprocessing workflows.
Advanced:
- 10m u-component,
- 10m v-component,
- 2m temperature,
- Boundary Layer Height (BLH).
This configuration supports extended meteorological characterization and legacy dispersion modelling workflows where thermal structure and mixing layer information may be relevant.
Pro:
- 10m u-component,
- 10m v-component,
- 2m temperature,
- 2m dev point temperature,
- mean sea level pressure,
- total cloud cover.
This preset provides a broader atmospheric context for more comprehensive environmental and climatological assessments. Users may request additional ERA5 variables directly from the Copernicus Climate Data Store.
WindRose Studio will read and inspect any variables present in the imported GRIB file.
The recommended presets reflect common environmental and regulatory workflows. Additional ERA5 variables may be selected directly on the Copernicus CDS portal and will be read and inspected by WindRose Studio if present in the imported GRIB file.
Step 5: Review and Submit
The final step of the Wizard presents the ERA5 Request Recap, summarizing the selected:
station location,
spatial subregion (N, S, W, E),
temporal coverage,
variable set.
This recap provides a structured reference for configuring the request within the Copernicus Climate Data Store (CDS) interface. The dataset request is submitted directly on the CDS portal. Once processed and downloaded, the resulting GRIB file can be imported into WindRose Studio for structural inspection and spatial interpretation in the Analyze GRIB phase.
The ERA5 Request Recap acts as a structured checklist to verify spatial, temporal and variable consistency before submission. Once downloaded, the resulting GRIB file can be imported into WindRose Studio for structural inspection and spatial interpretation.