This paper received two thorough and helpful reviews that raised several issues. However both reviewers were very positive about the paper and only minor revisions were requested. The authors have meticulously addressed reviewer concerns and I feel the revision does a very good job of responding to author comments. I have some minor editorial comments but feel this paper does not require much additional work: I look forward to seeing an edited manuscript and then the paper in ESURF.
I will add that one of the reviewers emailed me with an additional note:
In complement to my review (referee #2) for the Lupker et al paper ("10Be systematics in the Tsangpo-Brahmaputra catchment..."), I forgot to ask the authors to include in their references and discussion the paper by Lukens et al :

Lukens, C. E., C. S. Riebe, L. S. Sklar, and D. L. Shuster (2016), Grain size bias in cosmogenic nuclide studies of stream sediment in steep terrain, J. Geophys. Res. Earth Surf., 121, 978–999, doi:10.1002/2016JF003859.

This seems reasonable to add since the subject of that paper is of direct relevance to this manuscript.

S Mudd

I thank the authors for their corrections and look forward to seeing this manuscript in ESURF.

There is a single typo on line 15 of page 15 (there is a floating "y" that shouldn't be there) but I don't think this is worth another round of uploading files: hopefully the copyeditors will read this note and fix the typo.

This is a very nice paper that highlights how careful use of a mixing model can give us insight into erosion rates where we haven't got directly samples 10Be concentrations and I think other authors will be able to use the innovative techniques described here. It is an excellent addition to ESURF.

Simon

I am pleased to confirm acceptance of this paper, considering the positive comments from the reviewers and Associate Editor, and my own reading. Thanks to all for the hard work. I think the substantial dataset and detailed analysis should make a good contribution, both to understanding erosion in the Himalaya and to developing approaches for extracting information from detrital datasets.

A few minor editing notes to consider during the proof-reading stage are listed below. Other issues (including some inconsistencies in use of commas) will hopefully be addressed during copy editing. In reviewing the proofs, please make sure that all text on the figures is readable when the paper is printed (in some cases the text is small, so I imagine it will be unreadable unless the figures are full page width in the final layout).

page 1, line 31: constraints, not constrains
page 2, line 8: a sharp
page 4, line 3: perhaps refer to the figure showing pt. 8
page 4, line 14: was, not is (to keep tenses consistent)
page 4, line 18: at different facilities, not on?
page 8, line 13: farther southwards
page 13, line 24: superscript on 10Be
page 13, line 42: latter, not later
page 14, line 38: difference, not different
page 15, line 14: remove the errant y
page 16, line 17: concentrations, not concentration
page 16, line 18: provide, not provides (data are plural)
page 17, line 7: again, data are plural, so confirm, not confirms