The authors have made extensive changes as a result of the reviewers’ comments, and I believe the paper is now suitable for publication. They have enlarged and clarified the description of the model, and completely rewritten the results section (section 3) and much of the summary and conclusions (section 6), while the discussion section (section 5 has been enhanced).

The paper does need a good copy edit, as there are many examples where the authors’ use of English should be corrected. There are a few other points that need to be changed to avoid confusion. These are listed below, but are very minor and I do not need to see the manuscript again before publication.

In section 2.1.2, they state: “The default N, Fe and P atmospheric nutrient inputs of PISCES in the EC-Earth configuration have been replaced for this work by state-of-the-art monthly mean atmospheric deposition fields recently published in the literature.” Surely this needs a reference – should it be Duce et al. 2008?

In section 2.2.2 there is the statement “The highest annual mean DFe deposition fluxes into the ocean (Fig. 3c)….” This should presumably refer to either Fig 1e or Fig. S3c, not 3c, which is about changes in N fixation.

In section 3.1 on Fe deposition, I believe the final figure reference should be to S5, not S4.

In section 3.3.1, there is the sentence “Consequently, the model’s nutrient sensitivity is largest in the subtropics, in particular in the subtropical gyres where good light conditions and warm
waters support high growth rates, paralleled by diminished nutrient supply from depth due to Ekman pumping.” As written, this implies that the diminished nutrient supply is caused by Ekman pumping, whereas in fact Ekman pumping normally increases nutrient supply to the surface. This sentence could perhaps be rewritten as “….support high growth rates, despite the diminished nutrient supply from deeper layers.”