Dear Pieter et al.,
Thank you very much for your detailed responses to the referee reports.

In preparing your revised ms, and in light of both the actual model output and the caveat that the model holds subsurface nutrients constant, please make sure not to overstate the result that biology is not important. Similarly, given nutrient additions along the Lagrangian pathways of the AAIW and SAMW, make sure not to overstate implications for low-latitudes.

Once I receive a thoroughly revised ms, I will send it out for re-review.

Sincerely,
Markus

Dear Pieter et al.,

I have now received two reviews of your revised contribution. Based on these reports and my own reading, I will ask you to follow the recommendations of referee #2. Specifically, please clarify your statements about gradients: winter versus summer, and provide a more detailed analysis of model results as per suggestions from the second referee.

Once these changes have been introduced, I will send your manuscript out again for review.

Sincerely,
Markus

Dear Pieter et al.,

Thank you very much for submitting a thoroughly revised manuscript addressing the referees' comments in great detail. Both referees now recommend publication; referee #2 offers some minor, specific edits. Once you have addressed these, I will be happy to accept your contribution for publication.

Sincerely,
Markus

Dear Pieter et al.,

Thank you for making the changes to your manuscript as recommended by the referee. I am happy to accept your contribution as is.

Sincerely,
Markus