Dear Dr D'Andrilli,
I carefully looked at the the three referee reports and the comment made by Prof Andy Baker. I also read your replies to all these comments. I agree with most of the comments raised by the referees. Everybody recognises the pioneering work done, but the paper needs a careful and profound revision before it can be considered to be published in CP. My main concerns as an editor, regard the quality of the data. Both referee #3 and AB (and myself) claim that the DOC data (see Supp Mat) may be highly contaminated. This, considered with the use 'septa sealed' vials may have lead to a production of a unreliable data set. I would strongly recommend the use of a QA/QC protocol to demonstrate the suitability of the data for this present study. In addition, the application of the PARAFAC model must be carefully justified and fully explained in detail. This paper can really serve as a foundation for many studies on OM in ice cores in the years to come, but it must be considerably improved before its publication. I look forward to seeing a revised version of the MS.
Best regards,
Carlo Barbante

Dear Dr D'Andrilli,
first of all my apologise for taking so long to evaluate the revised version of the MS entitled A 21,000 year record of fluorescent organic matter markers in the WAIS Divide ice core.

I read the MS again in its revised form as well as the replies to the referees comments.

The MS has been greatly improved and I think it is now suitable for publication in CP.

Thanks for choosing CP to publish your interesting work.

Best regards,
Carlo Barbante