Dear Dr. Ziegler and co-authors,
based on the reviewer reports and your responses I invite you to submit a thoroughly revised manuscript, which will be re-assessed by the previous and potentially also new reviewers. I stongly encourage you to add the two suggested figures, and am convinced that a synthetic, conceptual figure will increase clarity and make the your work more broadly accessible.
Best regards,
Michael Bahn

Dear Dr. Ziegler and co-authors,

the reviewers are largely pleased with your revisions, and your paper should become acceptable for publication in Biogeosciences, once you have addressed the remaining minor issues, mostly concerning clarity. I look forward to seeing your final revised manuscript, which will make a relevant contribution to the literature.

Best regards,

Michael Bahn

Dear Dr. Ziegler and co-authors,

I have given your revised manuscript another look, and think that it should become acceptable after some further revision of the text. Please give the manuscript a careful read and improve the phrasing / wording to increase readability and clarity as much as possible. To illustrate my point, I have highlighted some critical passages in the introduction and legend of Fig. 1 in the attached file.

Furthermore I ask you to add a concise conclusion section, which highlights the main insights of your study in relation to the hypotheses and ends with a broader perspective.

Best regards,

Michael Bahn