Dear Author,

Thank you for posting replies to the referees comments. Please submit a revised version of your manuscript along the lines of your replies and also consider the following points:
- RMSE is the root mean square error (not "squared")
- The same data should, in principle, not be presented twice (see Table 1 and Fig. 5).
- In the revised manuscript, please clearly mention the limitations of the approach to measure NCC (uncertainty similar to the change) by providing some quantitative estimates of both.

Regards,
Jean-Pierre Gattuso

Dear Author,

Thank you for submitting a revised version of your manuscript under consideration in Biogeosciences. It could be accepted for publication after minor revision (see below). When submitting the revised version, please let me know which of the changes were not implemented, if any, and why. This would speed up final acceptance.

I look forward to hearing from you.

Best regards,
Jean-Pierre Gattuso


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- see comments provided in a pdf file by referee #1. Let me know if this file is not available to you.
- Section 2.4: I agree with referee #1. There are problems with the equations.
- Referee #1 is confused with the minus sign added at the beginning of the NCP equations. I assume this sign is there to make NCP positive. This is not the way to do it and I recommend adding vertical bars to indicate that the absolute value is taken. Like: |xxxxx|
- I suggest to use "l" and "d" for light and dark.
- Using different equations for the control and macroalgal metabolic parameters is a waste of space. Why not use the same equation like NCP = |(∆DIC_l - 1/2 x ∆TALK_l)| / T. And add below the set of equations "ΔDIC, ΔTAlk, and ΔDOC were calculated as the final minus initial concentrations in the control and macroalgal experiments."
- It is not a good idea to use multiple "/" signs such as "x V / B / T". It should rather be " x V / (B x T)". Is that right?
- 168-169 and 180-181: The source of the photoperiod and wind data should be provided: either a reference or the url of a web site.
- 173: K x S x (...)
- 178: 0.39 x U
- 185: I assume you did not do the calculation of the carbonate chemistry with a calculator but with a software. Which one?

Dear Author,
Thank you for submitting a revised version. I am sorry that it took longer than usual to get back to you. The current situation with Covid-19 did not help. Thank you for submitting a revised version of your manuscript submitted to Biogeosciences, which I am glad to accept for publication.

I look forward to seeing this paper published and thank you for considering Biogeosciences to publish these very interesting results.

Best regards,
Jean-Pierre Gattuso
BG Editor