POLARIS gridded soil layers: 2016 layers that are no longer in the 2019 product

The original citation by Chaney et al. (2016) included a link to gridded soil datasets for the contiguous USA. That link, http://stream.princeton.edu/POLARIS, no longer works. In 2019 Chaney et al. published a new paper on the POLARIS dataset and put out a new data link, http://hydrology.cee.duke.edu/POLARIS/. This new data link does not include the variables awc (Available Water Capacity), CACO3 (calcium carbonate), or resdt (depth to restrictive layer). Studies have used these now unavailable layers. For continuity I have included these layers for the uppermost soil layer (0-5 cm). The data are available as geotiff files at 250-mter resolution for the contiguous 48 states of the United States of America.