Dear authors,

Thank-you for the revised version of the manuscript and your response to the reviewers. I am satisfied that you have addressed all the comments, except in one respect. Both reviewers highlight that the timescale of sea-level deviations maybe significant for energy generation as well as the standard deviation or total range.

In particular, reviewer 1 says :
"In addition, a time period from 2007-2016 was chosen, which includes a strong barotropic salt water inflow event in December 2014 (driven by a strong sea level gradient between the Baltic Sea and the Kattegat). What influence has this event on the MSL variability and the WEC systems? What about other short term variability? Please also discuss this or why it is neglected."

Reviewer 2 also says: "I don’t even have a clear idea of the frequency of these large deviation sea level periods. Perhaps it would be useful to have a histogram of the sea levels at the representative location."

I agree, I think some sort of timeseries information would be very informative here. Whilst you are not providing the whole project, this does seem to fall under your remit, and would help other readers considering applying this method elsewhere in the world to understand your work. I suggest a timeseries of SL at representative points in the Baltic, which will address whether the range is linked to the 2014 event referred to by reviewer 1.

I am listing this as a major revision, but in practice I think it will not be too onerous.

Also, the tides in the Kattegat, which is included in your model domain and right through to Fig 10, are rather larger than the enclosed Baltic. Please check the tidal range and note knock-on effects as appropriate.

Regards,

Dr Joanne Williams, Editor

Dear Dr Castellucci and Dr Strömstedt

Thank-you for the further revisions to the manuscript. I asked for a further review from Reviewer 1, who remains concerned about the question of long-term variability. They say:

" The manuscript “Sea Level Variability in the Swedish Exclusive Economic Zone and adjacent seawaters: Influence on a point absorbing Wave Energy Converter” by Castellucci and Strömstedt investigates sea level variability to identify optimal locations for waver energy converters in the SEEZ. Therefore, they analysed a ten year sea level time series in the Baltic Sea and Kattegat area. I recommend publication after minor revision.

" As requested during the review process, a short discussion about the contribution of the sea level variability during strong salt water inflow events into the Baltic Sea to the maximum sea level ranges is included into the manuscript. As an example the inflow event in 2014 is discussed. The authors correctly pointed out that there is not a significant signal. This cannot be as the analysed time series is to short and includes only one strong salt water inflow event. However, the argument that there is no strong link between the sea level variations during a strong inflow events and the identified maximum ranges might be worth rethinking. Indication for that is the time period during a barotropic inflow events normally occurs during the months where highest SSH variability are identified by this study. For example the inflow event in December 2014 shows that after the precursory outflow period (03 Dec) the sea level at Landsort Norra was -47 cm and at the end of the inflow period it was +48 cm (see Mohrholz, et al. 2015), which amounts to 95cm and is about the maximum range in December 2014 (also visible in this manuscript in the new Fig. 3). This value is then included in the average.

" In addition, large short term sea level variability such as during an extreme event, in case captured in the SSH_1h time series, might also contribute to the maximum range of a month and therefore might influence the overall results. However, as sea level variability during inflow events are included in the time series and therefore in the process of identifying the optimal locations for the energy converters, analysing the origins of the maximum sea level ranges in different months and years should be investigated as future work. For now, it might be sufficient to reformulate the discussion if the authors agree with the argumentation above.

" Reference: V. Mohrholz, M. Naumann, G. Nausch, S. Krüger, U. Gräwe, (2015), Fresh oxygen for the Baltic Sea — An exceptional saline inflow after a decade of stagnation, Journal of Marine Systems, Vol 148, 152-166, doi: 10.1016/j.jmarsys.2015.03.005. "

Do you agree with this? If so, please amend the discussion accordingly.

Regards,

Joanne Williams

Thank-you for your response to the additional review and discussion point on salinity inflow events. I think that is sufficient for the scope of this study. Therefore the paper can go forward to the next publication stage.

Regards,
Joanne Williams