Dear Dr Lee

Thank you for your responses to reviewer comments. I would like to invite you to submit a revised manuscript, with revisions in keeping with your responses. In addition, I would like to ask that you include acknowledgement and discussion of reviewer points even where the data or analyses they requested (e.g. del 13C vs. FDOMp biplot) was either unhelpful or unavailable. This will ensure that other readers have those points answered as well.

Best regards,

Clare Woulds

Dear Dr Lee
I have read your revised manuscript as well as your responses to reviewer comments. Unfortunately I do not feel at present that sufficient revisions have been completed in order to allow publication. Reviewers requested substantial changes to the presentation and analysis of your data, therefore I would like to see a much more thoroughly re-worked manuscript.
I would therefore like to ask you to look at the reviews again, and make sure that you carry out revisions in response to every point. Overall there are quite a few places in the author response where you provide some of the additional explanations that reviewers requested, but you do not refer to how those enhanced explanations have been incorporated into the text. Please make sure that all such details are provided in your new response.
Please make sure that this revision of the manuscript is thoroughly done, as I will not be inclined to request further revisions.
In particular I would like to stress the following points:
Reviewer 2 stated that additional work was required on data presentation and analysis. I do not feel that the fairly limited revision of the text that has been undertaken satisfies the level of enhancement requested by reviewers. In your author response please make sure that you detail what text has been added / edited where in every case.
I would like to see a better link made between your description of Masan Bay and your study objectives (to characterise DOM sources). Please could you add some research questions here that address knowledge gaps in the literature, and which you do actually address with your data.
You have provide an answer to the last point made by reviewer 1. But have not detailed how this is reflected in the revised manuscript. Please provide additional detailed and/or a marked up version.
For me the material added to the introduction still does not answer the reviewer’s questions ‘… has there been no prior work on DOM in the region? What are the probable sources of urban DOM that could confound a simple binary mixing analysis?’ Please provide plain answers to these questions.
Both reviewers requested additional detail relating to the PARAFAC analysis. Please add this to both the methods and results sections, not just to supplementary material as has now been done. The paper should contain all important information without reference to the supplementary material.
Best regards,
Clare Woulds

Dear Dr Lee

Thank you for your revised manuscript. I think this is getting towards being publishable, but I would like to ask for a few more changes:

1) I still find the research objectives in the introduction rather vague. Please lay these out as research questions or hypotheses that you have tested, and which map directly onto the main findings that you summarise in your conclusions. Further, please make it clear how your study moves the field forward (perhaps focus on the combination of indices that you have used), especially in comparison to the previous studies of organic pollutants etc., and in terms of all such estuaries rather than just your study site.

2) Where you report statistical test results - r2 values - please name the text you used (linear regression?).

3) Where you state the isotopic values DOC end members please provide references.

Best regards,

Clare Woulds

Dear Dr Lee

Thank you for your most recent set of revisions. I am now happy to recommend publication.

Regards,

Clare Woulds