I have reviewed the author responses to the referee reports and the revised manuscript that was included as a supplemental file. The authors have clearly made significant revisions to the paper to address many of the comments made by the two referees. Following my review of the revised manuscript that was uploaded as a supplemental file, it is clear the fundamental changes to the scope of the paper, the included analyses, and the text were made. I believe that the manuscript has been significantly changed and that it now represents a very different and improved contribution (in terms of writing and analyses) than the initially submitted manuscript. Therefore, I believe that it warrants additional review by referees.

The authors should be commended for their efforts in revising the manuscript and responding to the referee suggestions.

The editor requests that the authors provide the revised manuscript for consideration by the referees (please see additional notes below).

Best wishes,
Brian McGlynn

Additional comment:

1) Equations #5 and #6 do not appear to have made it through the PDF conversion process and are not visible in the revised supplemental manuscript.

2) Quoted from the HESS web site: “Regarding author's changes, it is recommended to provide a marked-up manuscript version (track changes in Word, latexdiff in LaTeX) converted into *.pdf and to upload this changes document as supplement to the Author Comment.” If this is not possible given the magnitude of the changes, please state the changes in broad terms. I note that this was largely done in the individual response to reviews.

The authors have been thorough their revision of the manuscript and in their consideration of the substantial review comments from the first version of this manuscript. In this second round of reviews, the referees highlight some remaining revisions that should be made prior to acceptance of this manuscript for publication. I concur with all of their suggestions. Please consider each of the additional review comments and provide a response to these reviews and a revised manuscript. The paper should only be subject to editor review of these changes from here forward.
Sincerely,
Brian McGlyn

I have reviewed the author's responses to the referees. The revised manuscript has been improved by consideration of those comments and appears suitable for publication in HESS. The authors are thanked for their diligence in the editing process. I believe that the manuscripts has been substantially improved as a result of the referee's efforts and the revisions by the authors.
Sincerely,
Brian McGlynn