Assessment of L-Band SAOCOM InSAR Coherence and Its Comparison with C-Band: A Case Study over Managed Forests in Argentina
Round 1
Reviewer 1 Report
This is an interesting manuscript that demonstrates a rarely-seen L-band SAR dataset from SAOCOM. This work is important and should be published because of the potential to understand the effects of vegetation change from the perspective of spaceborne L-band SAR. However, the research itself is not particularly novel as it employs a fairly standard implementation of interferometry to assess the coherence of radar data over forests. Other than the application of the SAOCOM data (which is important in its own right--but not a contribution from the researchers), I cannot identify the novelty of this research.
The manuscript was well-written and well-organized with minor grammar mistakes-- consult with a free digital grammar checker such as Grammarly. The majority of my comments pertain to the organization and presentation of the figures.
Line 58-59 says that the SAOCOM data are 'available.' Please cite how to access the datasets publically. Are the SAOCOM data limited to Argentinian researchers only? As a part of open data access and research reproducibility, the data should be made available. (Also, the data availability statement at the end is currently blank. It is important for readers to be able to replicate the study). The availability of the SAOCOM data is additionally important for the publication of this article since the primary goal of the article is to demonstrate the efficacy and usability of the SAOCOM data.
3.1. Coherence Maps:: Please explain more about the relevant differences between L-band and C-band for deriving coherence. Specifically, it is common knowledge that C-band will have lower coherence and will lose coherence faster than L-band because of the short wavelength.
Line 364: "This work demonstrates that the Argentinean constellation SAOCOM-1 yields a good scenario for forest height mapping" This statement is not explained by the research, as the L-band coherence is not well-correlated with the GEDI heights, and the research does not attempt to derive interferometric heights from the vegetation. How is SAOCOM-1 useful for forest height mapping?
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Figure 5-6: Please fix the axis labels on Figures 5-6 to make the dates easier to interpret (such as Julian dates 1-365 or simply rotate the axis labels to include all of the dates).
Also, the color scale is not intuitive. Red is usually seen as a negative color, and here it shows positive values. The color bar was not easy to identify at first. (Please rotate the color bar and put it on the side-- only one color bar is necessary for all images).
Please spell out "temporal coherence"
Figure 7: Please include a label for the red line "Eq 9".
Figure 7-8 Please also spell out "Temporal Baseline/Perpendicular Baseline" on the x-axis labels.
Figure 8: Are the point sizes for Figure 8a larger than the points in Figure8b? Why?
Figure 9-10: Please include labels for HH/HV VV/VH polarizations (red and blue dots)
Figure 14: Please include y- and x-axis labels
Figure 15: Is this the same as the sub-figure from figure 4? If this is the same, then it can be removed as it is redundant.
Figure 16-17 The Coherence and Frequency axis can be limited to make better use of space. (X-limit 0-0.8 because the coherence values do not exceed 0.8; Y-limit 0-25)
Figure 18: Limit the x-axis to 5-30 meters for better use of space.
Author Response
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Author Response File: 
Author Response.pdf
Reviewer 2 Report
The overall intention of this submission is a good one. It is clear that the authors know a good deal more about assessment of the impact of temporal and spatial baselines on the interferometric coherence than about InSAR, but the manuscript is worthy of publication provided the following matters are addressed.1) Abstract. The authors should give the purpose and significance of this study, as well as the difficult problems that this article addresses.
2) Introduction. I believe that this section can be more concise, from the proposal and development of methods in this field to bottlenecks, so that readers can better grasp the opportunities and challenges of the current topic. Any way, it is proved that temporal and spatial baselines significantly affected interferometric coherence over every where, especially over the forested area. The authors with this aim, presented a comprehensive study by emphasis on how these effects vary between SAOCOM-1 L-band and Sentinel-1 C-band data. I think the introduction is not good as another section of paper, please explain more about related works. Moreover, the contributions of the work should be listed at the end of introduction for more readability.
3) It is recommended to include a discussion section to analyze the reasons for the experimental results, the limitations of the presented approach, and possible application scenarios.
Author Response
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Author Response File: Author Response.pdf
Reviewer 3 Report
Submitted article falls into the scope of Remote sensing journal and I found it to be a very interesting and beneficial contribution. The article is well written, appropriately supplemented with Figures and Tables.
Introduction section sufficiently describes the topic solved in the study. The study objective is clearly defined at the end of this section and is also in agreement with conclusion.
Materials and Methods deeply explain the calculation methodology, the data used and the study area.
Results are also clearly described.
However, I didn’t find the discussion section. I recommend authors to discuss their results with the results of other authors. The credit of this study is very high, and I believe that a well-written discussion could increase the impact on potential reader of this paper.
Perhaps I explained well why I recommend publishing this contribution with a major revision.
Author Response
Please see the attachment
Author Response File: Author Response.pdf
Round 2
Reviewer 2 Report
All of my comments well addressed by th authors.
Reviewer 3 Report
I'm satisfied with the correction and therefore I recommend publishing this paper in this current form.
