Impacts of Climate Change and Land-Use Change on Hydrological Extremes in the Jinsha River Basin

Round 1

Reviewer 1 Report

This study is important to support decision making related to predictive planning of risk-based water resources applications amid climate change. However, there are some issues which the authors need to address before the paper can be considered for publication.

COMMENT 1

It evident that trend analyses are central to this study. However, results from trend analyses

tend to be influenced by the choice of whichever method is involved. As part of uncertainty analyses, it is vital to take into account such influences by selecting a number of methods. Therefore, to take into account the influence from the selection of a particular method on trend results, the authors should implement in their study the CSD trend test. Then to reinforce their findings on trends, the authors could assess whether the results of trends from the Mann-Kendall test and  those from the CSD method are comparable. Common trend analyses methods such as Mann Kendall test are purely statistical. The advantage of the CSD method over the other tests such as Mann-Kendall test is that the CSD approach is both graphical and statistical. In this respect, the authors should also include some CSD plots where necessary.

The CSD method is implemented in MATLAB-based tool called CSD-NAIM. The link where CSD-NAIM can be downloaded from as well as the procedure for the CSD trend analyses can be found on pages 7 to 8 of the paper via the link http://dx.doi.org/10.3390/hydrology4040048

COMMENT 2

The climate baseline is well-known to be the period 1961-1990, why did the authors use another period outside the climate baseline?

COMMENT 3

The reasons why the authors selected particular GCMs should be given.

COMMENT 4

What are the limitations of this study and how can they be addressed in a future research?

COMMENT 5

The authors need to give a brief review of two things especially on the choice of (i) downscaling method, and (ii) hydrological model.

There a need for review on the influence of the choice of method of downscaling on climate change projections e.g. of rainfall (here, a mere google search can give you good information)

There must also be a brief review on the influence of the choice of hydrological model on the simulation of extreme events like the ones they considered in this study. Here, after the review, the authors need to give why they chose SWAT instead of other models. Again good information can be obtained from internet search by typing in the google search the text e.g. influence of the choice of hydrological model 

Author Response

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Author Response File: Author Response.docx

Reviewer 2 Report

It is a very interesting work with innovative elements. Some comments that might improve this work are following:

The information that is provided in the Appendix A and B should be removed from the last part of the paper and to be added in the methodology.

It must be clear from the beginning to the reader what are the available data.

The methodology section should be enhanced.

A paragraph to present more detailed  the climate data should be added.

More details about the input data to the SWAT model should be provided in the text (for example, land use map, soil map etc)

Did you take into account in the establishment of the SWAT model the reservoir regulations due to dams or other artificial constructions?

Figure 9 should be improved

Comments for author File: Comments.pdf

Author Response

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Author Response File: Author Response.docx

Round 2

Reviewer 1 Report

The paper is now greatly improved in both quality and content. However, some minor corrections to be made are below:

MINOR CORRECTION 1

Correct reference No. 59 to become:

Kendall, M.G. Rank Correlation Methods, 4th ed.; Charles Griffin: London, UK, 1975.

MINOR CORRECTION 2

Line 162: Change Charles Onyutha [61-63] to "Onyutha [61-64]".

Then add the first paper (see below) that introduced CSD method. TO do so, make reference 64 to become:

Onyutha, C. Identification of sub-trends from hydro-meteorological series. Stoch. Environ. Res. Risk Assess. 2016, 30, 189–205.

Thereafter, update numbering of references from Richter and Thomas(2007) onward accordingly.

MINOR CORRECTION 3

Line 297: Change "CSD test does" to become "CSD test does. The main reason for this realization is that when series are characterized by persistent fluctuations, the differences among trend detection methods become large [62]. Therefore, there is a need to consider a number of tests for trend analyses (as done in this study) to even out the uncertainty from the influence of uncertainty due to selection of a particular method on results.

Author Response

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Author Response File: Author Response.docx

Reviewer 2 Report

The maps do not have a north arrow to show the orientation. The weather stations symbol in the first map should be changed.

Author Response

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Author Response File: Author Response.docx