The data here were originally posted to facilitate timely and transparent peer review. The final public data release with formal metadata is now available from at the following location: Nauman, T.W. and Duniway, M.C., 2019, Predictive maps of 2D and 3D surface soil properties and associated uncertainty for the Upper Colorado River Basin, USA: U.S. Geological Survey data release, https://doi.org/10.5066/P9YBAKC2. Associated publication: Nauman, T. W., and Duniway, M. C., 2019, Relative prediction intervals reveal larger uncertainty in 3D approaches to predictive digital soil mapping of soil properties with legacy data: Geoderma, v. 347, p. 170-184. https://doi.org/10.1016/j.geoderma.2019.03.037 The raster layers in this dataset are the model predictions of various soil properties being created as prototype maps for more quantitative natural resource management. They are the model outputs for the paper currently accepted in the journal Geoderma entitled: "Relative prediction intervals reveal larger uncertainty in 3D approaches to predictive digital soil mapping of soil properties with legacy data". Data are provided in a beta version for review purposes only. These data are preliminary or provisional and are subject to revision. They are being provided to meet the need for timely best science. The data have not received final approval by the U.S. Geological Survey (USGS) and are provided on the condition that neither the USGS nor the U.S. Government shall be held liable for any damages resulting from the authorized or unauthorized use of the data. The final US Geological Survey data release is available online: Nauman, T.W. and Duniway, M.C., 2019, Predictive maps of 2D and 3D surface soil properties and associated uncertainty for the Upper Colorado River Basin, USA: U.S. Geological Survey data release, https://doi.org/10.5066/P9YBAKC2. The files are named in groups of 2-4 with the .tif file being the base raster grid and the other fields being supporting files used by various GIS software. The naming convention starts with the soil property abbreviation as follows and association with 2D or 3D approaches as follows: SOC_00cm_logK = 2D % wt soil organic carbon oc_0_cm = 3D % wt soil organic carbon sand_f_vf_psa_00cm = 2D % fine + very fine sands sand_f_vf_psa_0_cm = 3D % fine + very fine sands ph_h2o_0_cm = 3D 1:1 soil pH in water ph_h2o_2D_00cm = 2D 1:1 soil pH in water EC_2D_00cm = 2D 1:2 water soil electrical conductivity ec_12pre_0_cm = 3D 1:2 water soil electrical conductivity The next abbreviation is QRF indicating that the model was a quantile regression forest. The end of the filename can have several different formats: _QRF: This is the soil property prediction raster. _QRF_95PI_h: This is the upper 95% Prediction Interval raster. _QRF_95PI_l: This is the lower 95% Prediction Interval raster. QRF_95PI_relwidth: This is the 95% relative prediction interval raster that normalizes the width of the prediction interval to the original observation set used to train the QRF model. _bt after any of the file names simply means that the layer was back-transformed from a layer in transformed units (e.g. log).

Updated 2D EC relwidth layer to reflect corrections to an error in first version.