Headland Rip Modelling at a Natural Beach under High-Energy Wave Conditions
Round 1
Reviewer 1 Report
The work presented is very interesting, with novel results that are backed by field and extensive modelling work. It falls well within the scopes of JMSE, while the submitted manuscript is well written with clear and concise plots to assist result interpretation. I only have some minor comments.
minor comments
The authors note that aside from gamma and Chezy coefficient were XB default values. However, it is not stated if other parameters were tested (especially regarding wave breaking).
Also, regarding wave forcing, were gammajsp and s(preading) also taken as default or estimated by offshore wave data?
ln 66: missing space in ‘low-to’
ln 68: consider changing ‘limiting the finding genericity’ which sound strange.
ln 222: maybe it would be better to say ‘plus (minus) one standard deviation’
- 245: not sure I see the underestimation of Uc in SIG3 (it does not appear to be systematic throughout the tide as in SIG2)
ln 263-65: not sure I agree, especially for SIG1. Longshore component is generally overestimated, and cross-shore magnitudes are strongly underestimated (and direction is off). Overall, the modelled flow appears to have a stronger cross-shore component than the observed. Further down (ln267-9) you make similar remarks, so likely this is just an expression mishap.
ln 326-7: maybe change slightly to stress that the rip deflection turns fully cross-shore in this case?
ln 392: 2 setups in the phrase; morphological setup of the GPB?
ln 397: missing space before ref [6].
Ln 403: slightly confusing phrasing, consider changing to: …. circulation occurs, under which adjacent embayment….
Ln 406: consider changing ‘expression’ to ‘formulas’
Ln 423: maybe add comma between offshore and regardless
Figures
Many plot boundaries and shorelines (e.g. Fig.1c, Fig.2 to Fig.8) are too thick, in my opinion; I suggest reducing line width in these cases (this is just a suggestion for the aesthetics of the otherwise very good plots).
Also, it would be nice to: add the N direction in Fig1c; mention in the legend of Fig.2a that tidal level refers to right axis; correct the RMS subscripts in Fig.8 to make them concise between caption (uppercase) and plot legends (lowercase); caption in Fig.10 does not mention c,d,e; I see it is tight to fit Figs. 7 & 8 in 1 page, but maybe it could be worth it, as now it leaves too much blank space.
In Fig. A1c, does the ‘without islands’ refer to the bedrock formations?
Author Response
Please see the attachment.
Author Response File: 
Author Response.pdf
Reviewer 2 Report
This paper uses numerical simulations with XBeach surfbeat model to explore the dynamics of natural headland rip circulation under a broad range of incident wave conditions and water levels. The authors present a final figure showing the different modelled circulation patterns depending on offshore wave conditions and angle of wave incidence that can be extrapolated to other similar embayments in which circulation patterns might be also constrained by the adjacent embayment morphology. This research highlights the importance of including the influence of adjacent embayments into single headland bypassing expressions.
The research described here is interesting and relevant for publication in Journal of Marine Science and Engineering and the paper is worthy of publication after major corrections. The manuscript is well written and only needs some clarification and tidiness in certain sections.
Major comments
The introduction and the methods are a bit chaotic at the moment. The main aim of the paper should be phrased clearly and if this is a modelling study, this should be clarified at the end of the introduction.
L82-102: Rearrange the paragraph as the aim of the paper and what the paper is about is a bit buried at the moment. I understand the idea. You want to briefly introduce the observational study and then use it to frame/ justify the modelling study; however, the way is lined up in the paragraph seems that your paper is only about these observations until L86-87, where you start describing the findings of that study. This is very well done/clarified in the abstract. A simple way to fix this would be:
The findings of [22,23] can be added in a previous paragraph rearranging the second sentence of the last paragraph of the introduction (L83-84) in something like: “A field experiment by Mouragues et al. …” and then describe the experiment and the findings.
Start the last paragraph with the aim of the study.
Then, “Following Mouragues et al., a coupled wave-circulation model is used to give a detailed and large-scale description of the nearshore…”.
Materials and methods
I believe that a section with “Modelled scenarios” in Materials and methods is needed.
Field measurements
L117-132: Again mention to the deflection configuration described in the study by Mouragues et al. [23] as in the introduction. This section should be just description of the field data you are going to use in the study and how you will use it. Is it to validate your model? Is it complementary as you will also perform new analysis using the observations? You use measurements of wave and currents to calibrate and validate the model but is not clearly stated in this section. If you want to introduce your deflection events, you can add a different section after the model description that is “Modelled scenarios.” E.g., you are using significant infragravity wave height from the ADCPs to validate your model. This should be stated in this section.
Numerical modelling
L153-165: It is fine if you want to include the calibration in the description of the model; however, can you elaborate a bit more on the period(s)/ events you used for calibration? I.e., are the period(s)/ events you used for calibration the same ones that are being modelled? You should use different periods/ events for calibration and validation purposes.
Offshore wave conditions
L188-201: You mention the wave model is coupled with a circulation model, could you elaborate a bit more? How are the water levels introduced in the model? Is the input wave spectrum (measured in one point) used as forcing condition being extrapolated to the entire open boundary? I assume so, please clarify in the text. If you want to introduce all the forcing datasets in this section, just considered rename the section to something like “Model forcing datasets”.
Results/ Discussion
Modelled cross-shore and longshore velocities of the deflection rip during the two events are not always in good agreement with measurements. Softening some of the statements is recommended. Add a section with model limitations is recommended. E.g., in SIG1, agreement between simulations and observations of both wave heights is significant but the correlation and NMAE for the current magnitude is quite poor. Can you comment on that? Maybe adding the stats per variable per measurement location will help elaborate a bit more; you could leave the two bulk stats per simulated variable in the figure but add a table with the others.
Some parts in the discussion addressed some of the model limitations. This together with the previous comment could be merged and homogenise in a separate section with “limitations”. No sensitivity for different Tp has been performed, this should be also mentioned as a limitation.
Conclusions
Very nice and clearly stated.
Other comments
My preference is to use a comma after e.g. and i.e. in most cases. But as I said, it is just my preference.
L42: [e.g., 5,6,15–17].
L42: Remove “recent”.
L65-68: Rephrase. I would avoid the reference to “studies described above” and just say “field data-based studies to date have addressed… “. Additionally, what information “Except for the very scarce dataset and analysis of [15],” is adding? The way is phrased seems that Coutts-Smith used a very scarce dataset and the analysis was...? I assume that Coutts-Smith did some work in more stormy conditions, hereafter the “except” in the sentence, but in any case, the sentence is a bit misleading.
L78-81: Consider rearranging the last two sentences and subsequently try to revise the linking words: first statement of headland rip and then to deflection rips.
L83: Remove “recent”.
The citations in the article should be revised throughout the manuscript. For example, line 42, “The recent field data-based studies of [16] and [6] have…” should be “The recent field data-based studies of McCarroll et al. [16] and Scott et al. [6] have…”; line 44, “For instance, [16] highlighted…” should be “For instance, McCarroll et al. [16] highlighted…” and many other places. The authors should double check throughout the manuscript and revise them.
L113: Mention the location name (i.e., SIG3, SIG2…)
L123: “the two selected deflection events…” should be “during two selected deflection events (hereafter, event D1 and D2 in Figure 2)”.
Fig 1. In the figure caption “Colour indicates elevation relative…”, add “Colour indicates elevation (Z) relative…”. Mention what are Uc and UL. And SIG3, SIG2...? You need to specify if those are your measurement locations. The figure with the figure caption should be self-explanatory.
Fig 2. Miss parenthesis in “(D1 and D2 shown by shaded areas)”. (c) is peak wave angle of incidence with respect to the shore normal, in the figure θ is used and not θp. Be consistent between figure panels and figure caption. Theta is also used in Fig.1 and not θp.
Fig 3. Capital U30,M in figure caption and u30,M in the figure. Be consistent.
L229. First time AQ is mentioned! Please clarify the measurements in “Materials and methods” section.
L313: Revise “alter the most the mean flow patterns.”
L402-405: Revise sentence. First describe what multi-embayment circulation is and then state that when multi-embayment circulation occurs bypass expressions should be applied with caution. This circulation was first described in McCarroll et al [17] and further identified in Valiente et al (2020) https://doi.org/10.1016/j.margeo.2020.106270.
References: Update references number 19 and 34 with the published papers. 19 is https://doi.org/10.1029/2020JC017053 and 34 is https://doi.org/10.1016/j.coastaleng.2021.103860.
Author Response
Please see the attachment.
Author Response File: Author Response.pdf
Round 2
Reviewer 2 Report
Thanks to the authors for addressing the comments/ suggestions.
