Dear authors

After a thorough assessment of your manuscript and the comments by the reviewer, I believe that your manuscript can only be considered for publication after major revisions. I have also assessed the responses to the reviewers' comments and it is clear that you have carefully considered and will address most of them.

Please make sure that you address in the revised manuscript all comments by the reviewers. It is clear from your responses that you are planning to add further discussion and explanatory text addressing many of the comments, but it is important to address all comments. For example: Please provide more details to explain the methodology for the triple collocation methodology, which is explained in the response to the comment by reviewer #1 related to lines 155-160, but it has not been clearly stated that is going to be explained in the paper. Same for the response to the comment linked to lines 185-190. This will improve your contribution.

It will also be useful to include the TLM equations as supplementary materials.

I look forwards to receiving a revised manuscript.

Regards,

Dear authors

After a careful assessment of your revised manuscript and the two referee reports, I agree with both reviewers, that your manuscript will be ready for publication after minor revisions.
Please submit a revised version addressing the comments by reviewer #2, particularly on the methodological aspects related to the simultaneous assimilation of SMOS and SMAP data. Though this is the main issue, please address also the other issues raised by this referee in your revised manuscript.

Best Regards,
Patricia Saco

The authors have now addressed the minor comments of the reviewers. The manuscript has been revised accordingly and is now ready for publication.