Dear Dr. Echevin,
Thank you for your comments. Please, prepare a revised manuscript according to the reviewers' comments and your suggestions.
I look forward to receiving your revised manuscript.
Best regards, Christoph Heinze

Dear Dr. Echevin,
Thank you for your revised manuscript and your responses. The two referees have been quite positive already concerning the first version of the manuscript. According to my judgement you have addressed the points by the referees including the presentation quality.
I have two small requests:
1. The supplement must be provided as an extra file.
2. In all Figures (e.g. Figs. 1, 6, 7, 10, 17) where you use a green line inparallel with red lines: Please, use a different colour or different signature than green (dotted line for example). Otherwise colour blind persons cannot discriminate between the lines. I apologise for this late request. The request can be found in the manuscript preparation guidelines. We just had an editorial board meeting yesterday and all associate editors have been asked to take care of this point more thoroughly.

Under the condition that these corrections will be carried out, I accept your manuscript for publication in Biogeosciences. Thank you for using this journal and to publish open access.

Best regards, Christoph Heinze