Dear Authors,

Thank you very much for your point-by-point responses to the reviewers' comments. I believe your replies are mostly reasonable, but I would like to send your revised manuscript to the reviewers again for further review. So please submit your revised manuscript to us.

Thank you again for your nice effort to improve the manuscript.

Kind regards,

Koji Suzuki
Editor

Dear Authors,

Thank you very much for your revised manuscript. Below are minor comments on it from one of the previous referees. So we would appreciate it very much if you could make a further revised manuscript.

Thank you again for your nice effort to improve the manuscript.

Kind regards,

Koji Suzuki
Editor

—
Reviewer #1

I think that the author will need to take the comments below into consideration to improve the paper.

Page 7, line 5. Change “HCL” to “HCl”.
Page 7, lines 12-13. This sentence remains somewhat unintelligible to readers. It would be better to give a definition of iron solubility (It is usually given as the ratio of dissolved iron to total iron).
Page 9, Line 23 (and elsewhere). This manuscript uses both “chl a” and “Chl a”. Please unify them.
Page 26, References. Please add the newly cited articles to the reference section.

Thank you very much for taking into consideration the reviewers’ comments. I consider that your manuscript has been significantly improved. So we are very pleased to inform you that your manuscript has been accepted for publication in Biogeosciences. Before it is published, please consider my technical corrections below:

P3, L16: ... cyanobacteria as estimated from algal pigment signatures.
P8, L15 and P11, L12: , Not MilliQ or Milli Q, but Milli-Q.
P9, L5: 0.8 µm
P9, L27: Remove a space between “n” and “=“.
P10, L20: Suzuki et al. (2002, Deep-Sea Res. II) has not been listed in the reference list.
P11, L20: Use kPa as a SI unit, not mm Hg.
P11, L10, L15, L17and L30: 55Fe and H14CO3-. Use superscript or subscript numbers.
P13, L29: Remove a space immediately before “at”.
P17, L24: The 2 in CO2 should be subscript.
P19, L19–21: Suzuki et al. (2002, Limnol. Oceanogr.) also observed a remarkable increase in diatoms (fucoxanthin) at station OSP after Fe addition:
Suzuki, K., Liu, H., Saino, T., Obata, H., Takano, M., Okamura, K., Sohrin, Y., and Fujishima, Y.: East-west gradients in the photosynthetic potential of phytoplankton and iron concentration in the subarctic Pacific Ocean during early summer. Limnol. Oceanogr., 47, 1581-1594, 2002.

Thank you again for submitting your nice manuscript to Biogeosciences.

Kind regards,

Koji Suzuki
Editor