Boundary-Included Enhanced Water Storage Changes Inferred by GPS in the Pacific Rim of the Western United States

Round 1

Reviewer 1 Report

This is an excellent paper. Well prepared and interesting results. The methods are clearly described, results presented in an interesting way, and discussion is appropriate to highlight the scientific contribution. I have no concern in accepting for publication. 

Author Response

Dear Reviewer，

Thank you for your comments，the response file and revised manuscript can be seen in Email attachment.

Best regards,

Yingchun Shen

Author Response File: Author Response.docx

Reviewer 2 Report

This manuscript presents an interesting study investigating a new boundary-included inversion model to improve the terrestrial water storage (TWS) inverted from regional GPS vertical deformation data. Authors try to define a new discs load empirical function (DLEF) and consider the mass change effect from the near but outside region.  

I think the paper is well written and the results are consistent with methodology. Besides, it is easy to be replicated. I think the results are valuable and could be used by other authors, so in my opinion there are not drawbacks for the paper to be published. The method was clearly presented and the key results/conclusions of this study were appropriately showed.  I think the significance of this study is valuable and thus suggest accept it with minor revisions.

Author Response

Dear Reviewer，

Thank you for your comments，the response file  can be seen in Email attachment.

Best regards, 

Yingchun Shen

Author Response File: Author Response.docx

Reviewer 3 Report

This paper proposes an enhanced model for the inversion of GPS measured vertical amplitude of ground deformation due to hydrologic load to estimate terrestrial water storage (TWS) changes. The authors present references that support their recognition of all GPS measured vertical ground deformation biases, as well as loading near-field (not small-scale) and far-field (not large-scale) contributions that bias the inversion. However, for clarity, authors should present equations to show how each bias contribute to the biased measurement.

As to the GPS measured vertical ground deformation atmospheric and non-tidal loads, it is not clear if the mean monthly loads are applied to the daily GPS measured vertical ground deformation from JPL or to mean monthly vertical measurements and, if so, what is the monthly smoothing contribute to the vertical ground deformation amplitude. Please clarify.

As to the inversion model, the authors focus on the near-field unknown mass change, particularly from the boundary of regions with water storage changes, based on disk load empirical functions and independent of existing constrain from GPS sites, which is this work´s strong contribution. The inversion model is statistically assessed against ground-truth measurements and compared to the direct inversion model, accomplishing the authors objectives, that further point to the model’s limitations and future enhancements.

The paper is moderately well written, with corrections required, some of which are:

Line 32: “… techniques. To…” should be “… techniques to…”

Line 101: “… give more quality results…” should be “… give better results…”

Line 143: “… it is generally to…” should be “… it is common to…”

Line 187: “… in the interesting study region…” should be “… in the study region of interest…”

Line 225: “… From DLEF, We…” should be “… From DLEF, we…”

Line 259: “… Then we invers…” should be “… Then we invert…”

Line 439: “… results are consistence…” should be “… results are consistent…”

Author Response

Dear Reviewer，

Thank you for your comments，the response file can be seen in Email attachment.

Best regards, 

Yingchun Shen

Author Response File: Author Response.docx