Electromagnetic Field Variation of ELF Near-Region Excited by HED in a Homogeneous Half-Space Model
Round 1
Reviewer 1 Report
It is necessary to express the achievements of the presented work quantitatively in the abstract section.
Any figure quoted from another article requires citation.
Some paragraphs are so long in which makes reading these sections difficult.
The too many number of mathematical relationships is one of the disadvantages of this article. Please remove unnecessary items.
The quality of the provided simulations needs to be improved.
In Figure 4, it seems that there is always a constant error between the theoretical simulation and the presented work. Does this make sense?
Is it not possible to compare this work with similar works in the literature?
How can other non-ideal factors be considered in this work to make more accurate simulations?
Author Response
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Author Response File: 
Author Response.docx
Reviewer 2 Report
1. The title of this paper is too long. Please shorten the title by not more than 15 words to avoid any confusion.
2. The citation methods used in this article are not consistent. Reference [#] is not an appropriate method to cite the paper/article.
3. The title of the citation is not to be written in the main text.
4. On page 7 at line 199, it is better to use equation number instead of formula when the sign + or - is taken away.
5. at the end of each equation, no need to put a comma, confusing with the symbol ( ' )
6. For Figure 3, what is the unit for the colour bar on the right panel? if possible, a normalised value would be appreciable to determine the intensity of each part when a comparison is need to be done. It is advisable if all the sub-figures in Figure 3 can be combined on one page.
7. The abstract does not clearly show the results/findings of the works and it does not reflect all the work done in the result. The statement is too general.
The English used in this article is ok but it can be improved by a proofreader. The continuation from one sentence to another sentence is not clear.
Author Response
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Author Response File: Author Response.docx
Reviewer 3 Report
I thank the authors for their contribution in the field of electromagnetic wave propagation. Although the field is relatively mature, the article seems to present an interesting and potentially impactful novelty. Approximating the Sommerfeld integral at different limits offers tools that may simplify field computation in various interesting special cases. However, I would like to offer guidelines on improving the readability of the article. The article may be published after the changes.
1. The mathematical derivations of the article should be as self-contained as possible. Much of the notation in the article is introduced without definition. In particular,
1.1. the Sommerfeld integral never appears in the article explicitly, even when it is central to the discussion.
1.2. the circular cylindrical coordinate system is not introduced explicitly, even when it is used. The cylindrical coordinates, fortunately, are given in an illustration. But using the established terminology explicitly would make the discussion more clear.
1.3. the copious coefficients in the Sommerfeld integral expression (4)–(9) do not seems to be defined at all, even when they are not common knowledge.
I suggest that the authors use a Preliminaries section or a mathematical appendix to fix these issues.
2. The focus on sea water does not seem to be sufficiently justified. It seems that the model is applicable for any problem that involves dipole wave propagation over an imperfectly conducting planar surface. Focusing on sea water seems to understate the scope of the theory. Sea water can, of course, serve as a motivating example.
In the title of the second section, the word "mode" appears, even when the term is not used in the main text of the section. Perhaps "model" was intended. Because "mode" also makes sense in the given context, I leave this particular revision to the discretion of the authors.
Author Response
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Author Response File: Author Response.docx
Round 2
Reviewer 1 Report
Good Work!
