Coastal Waveform Retracking for HY-2B Altimeter Data by Determining the Effective Trailing Edge and the Low Noise Leading Edge

Round 1

Reviewer 1 Report

This manuscript discusses the reprocessing and retracking of altimeter data, especially close to the coastline where readings may be inaccurate.  The manuscript describes a new method to improve the quality of altimeter data in coastal regions.  The results are good, and the quality of the manuscript is fair.

There are several issues with the manuscript that should be addressed before it may be considered for publication:

1. Line 22: "reprocessing data" should read "reprocessed data"

2. Line 47: "altimeter flights" should read "altimeter flies"

3. Lines 52-77: The waveform retracking method is introduced as being based on the Brown-Hayne waveform model, but then subsequently, the name "Hayne" is omitted.

4. The fonts in the various figures are very small and should be enlarged to make them more legible.

5. There should be one or more figures added to the text on page 3 to make the text more understandable.

6. Lines 200-205: The font should be improved.

7. Line 217: "H" should be "h"

8. Lines 398-410: There are many constants and parameters used in the description of the algorithm. How are these chosen?

9. Equations (6) to (10): The font should be improved.

10. Some more background theory on altimeters, etc., would be helpful to the reader who is unacquainted with these topics.

Author Response

Thanks for your suggestion, my reply is in the Word.

Author Response File: Author Response.docx

Reviewer 2 Report

In this manuscript, the authors introduce a conventional re-tracking model to process the HY-2B Altimeter Data. The novelty is not clear and the manuscript is more like a technical report rather than a scientific paper. In addition, there are substantial grammar issues in the manuscript.

Author Response

Thank you for your suggestions to this paper. Since my poor expression did not accurately describe the work of this paper, I will briefly introduce the emphasis of this paper again.

First, the main problem of coastal waveform retracking is the pollution of waveform data, which is caused by the non-water reflecting surface. That means what I should do is to eliminate erroneous information from waveform data instead of modifying the waveform model to fit the erroneous information. Therefore, the focus and innovation of this paper are on the processing of polluted coastal waveform data.

Through the processing of the leading edge and trailing edge of the polluted waveform, the method provided in this paper can recover the effective information of the coastal waveform data and use the Brown model to get the accurate sea surface information. Compared with other coastal waveform retracking strategies, this method not only handles the distorted part of trailing edge but also modified the leading edge and improves accuracy of waveform valid Information recognition, and the process of trailing edge is under a new perspective about ‘effective trailing edge’. Furthermore, this method considers the noise of pulse signal, so it also has a slightly better performance in the open sea areas than the standard process of HY-2B SGDR data.

Regarding the format of the paper you mentioned, I have revised the structure of the article according to the editor's comments to make it more agree with the presentation of scientific papers and fixed incorrect grammatical expressions and lexical spelling. By the way, I did not modify some proper nouns, such as subwaveform retracking, retracker, mispointing angle.

Thanks again for your valuable comments.

Reviewer 3 Report

I send the review in the attachment.

Comments for author File: Comments.pdf

Author Response

Thank you for your suggestions to this article. I have fixed some spelling and grammatical errors in the paper, and supply some background about the coastal applications of altimetry. By the way, I did not modify some proper nouns, such as subwaveform retracking, retracker, mispointing angle.