Sensitivity of Remote Sensing Floodwater Depth Calculation to Boundary Filtering and Digital Elevation Model Selections

Round 1

Reviewer 1 Report

 

The topic of the article is interesting and stimulating. Here you can find my comments:

 

OVERALL: - Please, enlarge and re-arrange font sizes to guide the reader properly in all sections. All figrues must be composed of HD images. It is mandatory to improve the scientific quality of the whole manuscript.

-        Please, pay attention to the JOURNAL TEMPLATE in all sections, including tables, references, captions, units, equations, and Figures.

 

-        Please, insert all corrected axes and labels, in order to guide the reader properly in the understanding of the whole manuscript. In addition, please improve the contrast between colours.

INTRODUCTION: Please, introduce in the scientific background of your study the importance of using advanced image processing models in the monitoring, management, and forecasting of vegetated rivers (i.e.,

Lama, G.F.C., Errico, A., Francalanci, S., Solari, L., Chirico, G.B., Preti, F. 2020. Hydraulic Modeling of Field Experiments in a Drainage Channel Under Different Riparian Vegetation Scenarios. In Innovative Biosystems Engineering for Sustainable Agriculture, Forestry and Food Production; Coppola A., Di Renzo G., Altieri G., D’Antonio P., Eds.; Springer: Cham, Switzerland, 2020; 69–77; doi:10.1007/978-3-030-39299-4_8.

METHODS: Please, insert a Figure for each sub-section. This will improve the scientific quality of your study, as a great support to all the equations proposed here.

DISCUSSION and CONCLUSIONS: These two sections must be re-arranged according to the suggestions indicated by the reviewer.

Author Response

Thank you for the useful review. We made the following revisions to address your comments: 

We have revised figures 1, 2, 5, and 6 to be more readable and of higher quality.

Introduction: we, respectfully, think that we well framed the scientific background and that the reference suggested is not relevant. 

Methods: we respectfully disagree. The manuscript already includes 12 figures.

Discussion and Conclusions: we separated the two in the revised manuscript.

Reviewer 2 Report

The author introduced an interesting version of the Floodwater Depth Estimation Tool (FwDET) (FwDET2.1) by adding the boundary cell smoothing and slope filtering procedure to reduce local biases in the FwDET predictions. As for me, this manuscript is well written and very applicant for remote sensing and geosciences areas. I have some minor suggestion to improve the presentation of the manuscript that should be applied before publication. 

1-       Page 1- Lines 33-36, "the Considerable advances in the availability of satellite data, ease of data acquisition, and cloud-based processing systems (e.g., Google Earth Engine (GEE)) have led to a new paradigm in the development and implementation of remote sensing flood mapping platforms." This sentence need to citations, I recommended to cite this sentence to following citations: 

https://doi.org/10.3390/rs14143253

https://doi.org/10.1109/JSTARS.2020.3021052

2-      ICEYE’s Flood Insights Product is the world’s first global and always-on data utility developed for the unique needs of insurers and Emergency Management organizations which is based on the SAR images. They developed good tools for flood monitoring and depth of the flood for disaster. However, this platform is not open source. Please refer to advantage of the FwDET2.1 than the ICEYE’s Flood software in the introduction. 

https://www.iceye.com/solutions/flood-monitoring

3-      Page 3, Equation 1 is not clear. I can’t see part of the formula. Please use the correct format of the journal. 

4-      Figure 1 is not clear. Please use high quality image for this figure. 

5-       The layout of Table 2 and 4 are not fit and some texts were superimposed to line number. Please correct this. 

6-       X axis of Depth histogram comparisons in Figure 5, should be horizontally presented. 

Author Response

Thank you for the useful review. We made the following revisions to address your comments: 

1. A new reference was added.
2. We added ICEYE as an example but we cannot discuss it as their water depth methodology is not published (to our knowledge).
3.  The MDPI template does not allow equation objects so we will need to get the journal to create a proper equation in the final version.
4. Done.
5. Fixed as much as we can on the template. 
6. Fixed

Reviewer 3 Report

Major comments

Add a flowchart showing the calculation methodology for FwDET2.1.

Figure 6d should show differences in m. Figure 6e Histogram should present the differences in m.

Minor comments

Figure 2 Units for slope (%) should be completed.

Table 3. Complete the units for slope (%) and absPBIAS (%).

Table 4. Units for absPBIAS (%) should be completed.

Figure 5 All figures should have the same scale on the vertical and horizontal axes.

Figure 6. The description (d) percent difference map [100(FwDETv2.1-benchmark)/benchmark] is not clear. It should be [100(FwDETv2.11 [I10, S0.5]-benchmark)/benchmark].

References should be compiled according to the guidelines for authors.

Author Response

Thank you for the useful review. We made the following revisions to address you comments:

We considered adding a flowchart but, given the number of figures already in the manuscript, decided to refer the reader to the one in our previous papers (line 81). We acknowledge that this is not ideal but the methodological additions to the tool in this version are easy to explain.

Figure 6 was revised as suggested

Figure 2 was revised as suggested

Units added to tables 3 and 4.

Figure 5 was revised as suggested

The caption of Figure 6 was revised as suggested. 

The references were revised according to the template instructions. 

Round 2

Reviewer 1 Report

The paper is suitable for publication