The Use of Satellite Data to Determine the Changes of Hydrodynamic Parameters in the Gulf of Gdańsk via EcoFish Model

Round 1

Reviewer 1 Report

I attach a file with comments.

Comments for author File: Comments.pdf

Author Response

Please see the attachment.

Author Response File: Author Response.pdf

Reviewer 2 Report

The Use of Satellite Data to Determine the Dynamic of Hydrodynamic Parameters in the Gulf of Gdańsk via EcoFish Model

By Maciej Janecki, Dawid Dybowski, Jaromir Jakacki, Artur Nowicki and Lidia Dzierzbicka-Glowacka

 

The manuscript describes the implementation of a simulation with data assimilation of the circulation at the Gulf of Gdańsk. The manuscript is easy to follow, describes the input data and provides a varied amount of statistics that may be useful for other researcher interested in the dynamics of the Gulf of Gdańsk. However, it is unclear what is the novelty of this work and what is the status of the fish module, and the assimilation of chlorophyll.

Readers wanting to repeat or follow the experiments are not being provided with enough information about how to do that. For example, the CESMS System can be implemented wither with the POP model or the MOM model. The authors do not say explicitly which one is being used here. The description of the model setup is poor. No information about the model time step, the horizontal and vertical diffusivity and viscosity schemes. the Surface and bottom drag formulations, relaxation times for the open boundaries. Does it use a sponge layer? How many points are used in the sponge layer? albedo? etc. For the spin-up, nothing is said about the initial conditions, the boundary conditions, the river runoff and atmospheric forcing during the set up. Similarly, it is unclear how precisely has the data assimilation been implemented. What are the values of the parameters listed in lines 224-236? The equation 3 is applied to all the surface of the model or only to those points with valid SST retrieval?

As such, this reviewer suggests the editor of Remote Sensing to accept the manuscript only a major revision is done by the authors.

General comments:

Abstract: The abstract should express the kind of experiments being described in the manuscript. In particular, it should state that the data to be assimilated is the SST. In this version of the manuscript it takes five pages for the reader to know what data are going to be assimilated.

All the results in Section 4 should display the ocean parameters (temperature, salinity, sea level, ocean currents) with and without data assimilation. Accordingly, section 4.1.3 should disappear and the content should be merged with sections 4.1.1 and 4.1.2. Similarly, Section 4.2 should also compare the results with and without assimilation.

Is there a reference to the 3D CEMBS model?

About the assimilation. Why the authors did not assimilate a subset of the in-situ observations, leaving the other subset for validation.

Small edits:

Line 13. Narrow straits: Can you please specify width and depth of the Straits?

Line 18: The highly urbanized ...

Line 23: Consider using the more common “heterogeneity” rather than less common “Diversification”.

Line 30: Consider using “combined” rather than “coupled”. Coupled usually refer when each component interacts with the other. In this application, the data are not modified by the outputs of the ocean model.

Line 30: Some “modern” observational technologies are also being applied to in situ observational Systems, not only to remote sensing.

Line 40: What are these “most important variables” ?

Line 56: “Effective domain”. What effective means here?

Figure 1: Please, label at least one isobaths (e.g. 100 m). Add place names as for example, Hel Peninsula, Puck Bay, Cape Rozewie, Cape Taran, Gdynia Orlowo, Władysławowo or the Sambia Peninsula. If possible, indicate the location of the rivers used in the simulation.

Page 73: What ocean model is being used here: POP2 or MOM6? Both are distributed by CESM.

Line 109: Why are you using both specific humidity and dew point temperature? The specific humidity can be estimated from the air temperature, dew point and sea level pressure.

Table 2: Can you include the annual mean transport of these rivers? It helps readers to assess the potential impact of each one of them.

Line 169: MIDAS CTD.

Line 213: The given reference [16] does not describe the assimilation module.

Equation 3: This correction is applied to every point of the domain or only the points with observations? And, is this equation applied every model time step or at intermittent steps ?

Equation 3: According to the parameters listed in lines 224-236. What have been the choices used in this work?

Figures 3 and 4: The impact of the data assimilation would be more clear if the authors show the no-assimilation results at those dates.

Line 271:  the MIDAS CTD instrument ...

Line 275: The use of the word “correct” is misleading here. To avoid misinterpretations, better use the concept of “impact of the assimilation of satellite SST”.

Line 276 (and following): “undercut” is not the usual verb. Consider using the more common “underestimate”.

Table 3: This table should directly compare the results with and without data assimilation.

Line 331: hat -> that

Line 331: “perfectly” ? That is a strong statement. Scientific style advocates for the elimination of this kind of adverbs.

Line 351-354: Are you talking about the model simulation or the observations? Or both? You could check the origin of the excessive homogeneity of the deep salt distribution? Is it present in the boundary conditions? You could check if the parent 3D CEMBS solution has homogeneous deep salinity.

Line 355: Again “correct” is not the concept to be used here. However, this reviewer suggests that the discussion of section 4.1.3 should be done simultaneous to the description of the simulation with assimilation, i.e. sections 4.1.1 and 4.1.2.

Line 364: Change “greater” by “larger”.

Figures 10, 11, 13, 14, 17 and 18 include a sponge layer?

Lines 670-674. What about nutrients?

Author Response

Please see the attachment.

Author Response File: Author Response.pdf

Round 2

Reviewer 2 Report

This reviewer recognizes the effort done by the authors to answer the main issues raised in the previous revision round. As these issues have been correctly addressed, this reviewer suggests the editor to accept the manuscript for publication after minor revisions are addressed by the authors.

 

Small edits:

Lines 1-2. The first statement of the abstract is so general, that it makes no sense to point out “the complex structure of parameterization” of a system that might be anything. The authors could directly refer to the ocean circulation in the Gulf of Gdańsk or to refer more generally to the ocean circulation or similar.

Figure 1: The map in Figure 1 contains more information than before, well done. However, consider increasing the character size. Also, to simplify the reading of the manuscript, the authors should indicate the meaning of the numbers or refer to the table 2 in the legend of the figure.

Line 87: “real models” ?

Lines 93-94: Unclear. Please rephrase.

Line 95: has ITS own time …

95: The CICE time step is 10 minutes and it is equal to the coupling time step.

Lines 96-98: Are you talking about the barotropic/baroclinic time-splitting method? In this case, why the use of “typically”?

Lines 245-258: Place the used values at the end of each explanation (once the reader has an idea of the possible choices available) and not at the beginning.

Figure 7 (and 8): Can the legend be placed in an area of the plot that does not hide the plots? Why the normalized vertical elevation? The POP is a z-level model, there should be a unique relationship level and meters.

Line 433: the summer ONES.

Line 451: The strong seasonal variability could be stated already at line 430, because from that point the authors are already talking about seasonal features.

Figure 11 (and 13): Never cited or discussed in the text. It merits some discussion about the non-homogeneous impact of the assimilation.

Lines 571-572: Replace the two line-long statement for a shortest version as, for example, “The model has been used to simulate the hydrodynamics of the Gulf of Gdańsk.”

Line 580: open BOUNDARY.

Line 656-659: Rephrase. The first two statements of this paragraph reiterate the same information. Make more concise.

Author Response

Please see the attachment.

Author Response File: Author Response.pdf