Ground Deformation in Yuxi Basin Based on Atmosphere-Corrected Time-Series InSAR Integrated with the Latest Meteorological Reanalysis Data

Round 1

Reviewer 1 Report (Previous Reviewer 2)

Please see attached file.

Comments for author File: Comments.pdf

Author Response

Dear Reviewer,

I have uploaded two word files, one with a point-by-point response and the other with the revised manuscript, and I have indicated the exact location of each change in the point-by-point response file so that you can quickly see it in the new manuscript.

Kind regards

Author Response File: Author Response.docx

Reviewer 2 Report (New Reviewer)

Dear Authors,

This paper deal with the development and implementation of atmospheric delay correction on multi-temporal SAR data over the Yuxi basin in China. The atmospheric correction method is developed based on ERA-5 data. It is also compared with MERRA-2. The SAR data used are RadarSAT-2 and Sentinel-1A covering the period between March 2020 and March 2021. Doris was used to prepare the interferogram and StaMPS for the PSI processing. The study of three ground movements in the Yuxi basin was used to highlight the increase of quality of the processed data.

The paper requires some minor editing before being almost ready to publish. Globally the paper is well written and properly illustrated. I hope to see it published soon.

Kind regards

Please find below some suggestions:

L34-35: I suggest that you deleted the end of the sentence after “certain area”. Or make two sentences because as it is now, I don’t understand how the end is connected to the beginning of the sentence.

L40: Could you provide a reference that mention the 50 or so large cities affected by subsidence in China. That would be helpful for the reader

L45: I suggest that you rephrase the sentence by saying that the GPS is capable to measure the displacement of specific points and that this displacement is related to a subsidence phenomena

L54-55: I suggest that you rephrase the sentence: Particularly, the change in atmospheric elements for the micro….. and stop the sentence at interferogram. The next one would be : A single path…..

L61: Could be good to add the reference of Berardino 2002 for SBAS

L13: just use ECMWF since it is already explained at line 105

L189,198: provide a ref for DORIS and SNAPHU please.

L234: Typo error, it is Figure 2 b

L349: typo error add a space between : and and pressure

Figure 9: I would add in the legend that the black dotted lines are faults since you use them after in the text.

L564: Please describe GPM as NASA Global Precipitation Measurement Mission

Author Response

Dear Reviewer,

I have completed point-by-point response. Please see the attachment.

Best wishes

Dr. Guo

Author Response File: Author Response.docx

This manuscript is a resubmission of an earlier submission. The following is a list of the peer review reports and author responses from that submission.

Round 1

Reviewer 1 Report

Dear authors, thank you for your manuscript. It regards correction of InSAR interferograms and time series according to ERA-5 and MERRA-2 atmospheric models.

The manuscript is well structured, well written and comprehensible, I only have few comments.

- line 52: "15-20 cm magnitude". This is an absolute number which is not so important in InSAR (because of spatial referencing). It would be more useful to disclose delay variation per km.

- section 2.1, equations: some equations contain indices "dry", while other contain indices "hydr". I suppose it should be the same

- line 188-189:"advantage of the StaMPS algorithm is that it does not need to consider the surface deformation a priori information" - I don't understand, please make the sentence more clear. No algorithm I know needs such an information, except for the position of the reference point. And, in case of StaMPS, the result is referenced to the average of all points, so in your case with large displacement areas, you would detect (without post-referencing) false uplifts in all the other areas.

- section 3.1: Is the Yuxi Basin in China?

- section 3.2.1: you disclose acquisition time in UTC. Please disclose also local time (or the information morning/evening), this is important with regard to the atmospheric variation

- line 288: you disclose 24 days both for S1 and RSAT, but this does not correspond to fig. 4

- line 95: "for radarsat-1, the average difference between the two methods is only" (please discuss if the difference w.r.t. S1 can be caused by morning/evening acquisition times)

- fig 3: is it possible to make the topography of the cropped image more detailed?

- fig 4: is it possible to disclose also unwrapped phase after atmo correction?

- fig 4: can you please put the size of the image in pixels or in km? height range in the area?

- fig 4: please do the color scales comparable. I understand that the absolute values are different, it should suffice to make the same range of the color scales

- lines 330-340: you mentioned interferograms that were improved, but do not mention the other ones

- figure 9: I would appreciate if the leveling measurements would be included here, too

- figure 9: could you please disclose also original time series (without ERA-5 application)?

Minor mistakes / typos:

- line 49: atmospheric -> atmosphere

- line 49: "will appear delayed effect"

- line 62: satellite -> satellites

- line 81: does -> do

- line 90: "Li combined with GPS" (it is not clear WHAT was combined)

- line 120: we proposes an -> we propose a

- line 163-164: q1, q2, t1, t2 should be lower index

- line 176: coregistratied -> coregistrated

- line 203: assumes -> assume

- line 205: horizontcal -> horizontal

- lines 258-260: please reformulate

- fig 4: unwrap phase -> unwrapped phase

 -line 320: We -> we

- line 327: "indicates the higher the atmospheric delay correction effect"

- figure 6: interference -> interferogram

- figure 8 (and other incidences): level -> leveling

- line 459: two SAR data -> datasets

- line 478-479: please reformulate the sentence "area C exists a small..."

- line 502: causes a ground The

- line 509: drops to have

-line 540: declines -> subsides

- line 547: uplifting -> uplift

- line 610: technology should be increased

 

Reviewer 2 Report

Please see attached file.

Comments for author File: Comments.pdf