Dear authors

Thank you for your detailed reply to the review comments.

Both reviewers have assessed your manuscript and find it suitable for publication after revision. Based on the review comments, your reply and my own reading, I would like to invite you to submit a revised manuscript. Please also upload in addition a pdf file where your text changes are highlighted (e.g. using the track change features of Microsoft Word or similar) to ease the further assessment of your work.

I note that the inclusion of additional tracers such as 14CO2, 18CO2, CO, and 222Rn would involve a lot of work and is likely outside the scope of your current study. I do not expect you to include these tracers in your analyses. You may consider to briefly discuss these additional tracers in your concluding section.

Thank you for sending your work to Biogeosciences,

With best regards, Fortunat Joos

Dear Authors

Thank you for uploading a revised version of the manuscript and for your detailed reply to the comments by the referees.

I am happy to accept your manuscript for final publication in Biogeosciences. This decision is based on your reply to the review comments, your revised manuscript (including a version highlighting changes compared to the submitted version), the initial review reports, and consultation with reviewer 2. Reviewer 1 recommend the publication of the initial version subject to minor revision. Reviewer 2 recommended the publication of your work after having seen your reply to the review comments.

Thank you for submitting your work to Biogeosciences.

With kind regards, Fortunat Joos