In this paper by Winton and co-authors the results achieved from  a 120 m deep ice-core are presented. The ice-core was drilled in the DML region (close to Kohnen Station) in 2017 in the framework of the ISOL-ICE project. The main results shown and described  in the paper can be summarised in: production of a chronology for the last 1349 years, the history of the accumulation rate at the site along this period and the chemical profiles of selected markers (mainly nitrate, MSA and sea spray species). The chronology was built via annual layers counting with the aid of selected accurate age markers to be used as tie points (volcanic eruptions). The authors clearly write that this work is just the first part of the full job to be done in the framework of the project and I agree with them that the reconstruction of the accumulation rate is very important to better understand the nitrogen isotopes variations in nitrate. We all agree on the importance of the study of the TCO variations in the past but, in this paper, this topic is not studied at all and some sections of the Abstract and of the Introduction should be “cleared” at least in part since they are a bit misleading. I think that especially the Abstract should not give all those details about TCO, UV radiation and nitrogen isotopes. The discussion about the importance of this topic is properly described in section 4.2.

Regarding the chronology, the authors declare an estimated uncertainty at the bottom of the core of 3 years. I have two questions for this point:

1. How was the uncertainty estimated? Is it a sum of the “uncertain” annual layers?
2. Since you have several well-known volcanic age markers, I would expect the maximum uncertainty in the middle of the largest interval enclosed between volcanic peaks. Which is the maximum uncertainty along the core? Does it coincide with the bottom uncertainty?

All along the manuscript the authors use Na and Mg but from time to time they use the ionic form. I know that the authors measured the “total” content of the two species but, as stated at line 139, the total is assumed to represent mostly the ionic specie. The same thing holds true for chloride which is sometimes Cl- and other times Cl. I think that the ionic forms would be to be preferred all along the text.

Figure 3 (a) shows an interesting “dip” a few years before 2000 but this feature is not discussed in the text. Do the authors have a possible explanation for this section? Such significant variations in the accumulation rate will be basic in correctly interpret the N-nitrate isotopic changes and thus past surface-UV and TCO implications.

Minor comments:

Line 19: when the authors speak about an extension of the previous records by two decades, I guessed that was an extension back in time but I understood later that it’s an extension towards more recent years. Elsewhere in the manuscript this was correctly said. I invite the authors to correct this expression in the abstract in order to clarify this point.

Line 132: insert a space between Cl- and “was”.

Line 139:  change to “are assumed”

Line 263: change “with SAM …” to “between SAM…”

Line 488: change the full stop before “While” in a comma.

Figure A3: bottom panels: y-axes add + to Na in both panels

Table A2: I would prefer “Deposition date” instead of “Arrival date” in the title of the third column.

Table A3: the SAM/accumulation R should be bold

Please see my review in the attached pdf file.