All reviewers see the value of the work, but also point out a number of problems with the paper, including significant overlap with some recently published papers, and problems with assessment of the uncertainty and the reference model. Several reviewers gave many detailed comments on a supplemental pdf. The authors need to modify their paper so that it is clear what is new, especially with respect to these recently published papers. The section on uncertainty needs to be modified, and the reference model can probably be removed. The title needs to be revised to reflect the contribution of the paper.

The authors have done a good job revising the paper and responding to the comments of the reviewers. Specifically, they have highlighted their contribution and substituted references to other work where possible, they improved the explanation of the 'clay fraction concept', and they benchmarked their model through comparison with four other models.