The ensemble version (indicated with a 'e' in the version number) is available on a 0.1 and 0.25 degree regular grid for the elements (daily mean temperature TG, daily minimum temperature TN and daily maximum temperature TX). They cover the area: 25N-71.5N x 25W-45E. The data files are in NetCDF-4 format. The Global 30 Arc-Second Elevation Data Set (GTOPO30), a global raster Digital Elevation Model (DEM) with a horizontal grid spacing of 30 arc seconds (approximately 1 kilometer) developed by USGS is used for the elevation file as well.
The ensemble dataset is constructed through a conditional simulation procedure. For each of the 100 members of the ensemble a spatially correlated random field is produced using a pre-calculated spatial correlation function. The mean across the 100 members is calculated and is provided as the "best-guess" fields. The spread is calculated as the difference between the 5th and 95th percentiles over the ensemble to provide a measure indicate of the 90% uncertainty range. For more details see Cornes et al. (2018) and the guidance on how to use ensemble datasets.
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