Why do the coordinates in my history+ data file differ from the coordinates I selected?
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The coordinates of the activated location and the ones on the data output do not exactly match each other, as the downloaded file shows the coordinates of the grid cell centre, where the desired location is, not the coordinates of the desired point. Each cell represents an area defined by a centre point and a diameter. The coordinates shown are the centre point coordinates, and the diameter depends on the spatial resolution of the grid cell, which is between 4 and 30 km, depending on the location and period. The weather data are always calculated for the entire grid cell, which is why you purchase data for the whole grid cell, and all coordinates within the grid cell are also covered in your subscription. You will not see differences in the data when comparing different locations within the grid cell. However, weather variables like temperature are downscaled to the respective altitude of the location. To select the appropriate grid cell for a desired location, several criteria are taken into account:
- Selection of grid cells on land - Elevation of the grid cell compared to the desired coordinate
- Proximity to the desired point - the 4 closest grid points are considered and the one that best matches the desired criteria is selected, otherwise the closest one is selected.
