Temporal and Spatial Changes in Evapotranspiration and Its Potential Driving Factors in Mongolia over the Past 20 Years

Round 1

Reviewer 1 Report

1) General Comment

 

In this study, ET trends were investigated using surface evapotranspiration time series data for the last 20 years in Mongolia. In addition, the authors used socioeconomic indicators as well as distributed grid data as input data to characterize the effects of natural and anthropogenic factors on ET.

Several statistical analysis techniques and indices are applied, and it is considered an interesting study to analyze the potential driving factors of ET from various viewpoints along with trend analysis.

The paper is generally well written and structured. The abstract represents the overall research content and results well, and the discussions are very thorough. And the conclusion also summarizes the key point of the manuscript well, so it is expected to provide useful information to related researchers. I am happy to recommend acceptance of this manuscript.

 

 

2) Specific comment

 

1. The spatial resolution of evaporation, NDVI, climate data, and topographic data used as input data in this study does not match. What is the spatial resolution at which the research was conducted?

 

2. Various remote sensing data (surface evapotranspiration, precipitation, soil moisture, surface temperature, net solar radiation) were used in this study. It is known that bias correction techniques are generally applied to remote sensing data to improve accuracy. This study did not deal with this aspect sufficiently, but I wonder if the data used have sufficient representation of Mongolia in terms of time and spatial resolution.

 

Author Response

Thank you for your letter commenting on our manuscript entitled "Temporal and spatial changes in Evapotranspiration and its potential driving factors in Mongolia over the past 20 years"(ID: remotesensing-1592552). At the same time, I would like to appreciate you for spending your valuable time to contribute to our study. We also appreciate your encouragement and support, which is very important to us. The comments are not only valuable and helpful for revising and improving our paper, but also have the important guiding significance to our studies. We have studied your comments carefully and have made corrections which we hope meet with approval. The revised part is marked in bold green on the manuscript. Please see the attachment for the main corrections in the paper and comments on the reviewers.

Author Response File: Author Response.docx

Reviewer 2 Report

This study has two distinct characters. One part is very well written, interesting, and scientifically sound. This concerns the utilization of the extensive datasets on important components of the water balance and the statistical analysis using efficient tools, providing factual information for a broad and interesting region with peculiar conditions. 

The other part that concerns the interpretations and the discussion of the involved mechanisms and causes behind the presented conditions. These part includes erroneous and unjustified interpretations based on wrong assumptions and speculations. The final conclusions of the study are therefore erroneous and/or unjustified and not supported to the data.

The introduction also fails to present clearly the objectives of the study and the methodology, while informative, do not provide a clear description of the pathway towards the objectives.

I believe that the study still has some merit but it should stick to the facts and try not to obtain conclusions that are not based on the data or that contradict the physical mechanisms. I provide specific detailed comments about all these in the commented pdf file attached. 

Comments for author File: Comments.pdf

Author Response

Dear Reviewer:

We thank you for your letter commenting on our manuscript entitled "Temporal and spatial changes in Evapotranspiration and its potential driving factors in Mongolia over the past 20 years"(ID: remotesensing-1592552). At the same time, I would like to thank you for making important contributions to our study by spending your valuable time. Your keen and thorough analyses have benefited us a lot. Furthermore, your detailed and professional comments are very valuable for the modifications and improvements of our paper and have important guiding significance for our research. We also appreciate your encouragement and support, which is very important to us. We have carefully studied the comments and corrected them in the hope of approval. The modified part is marked in bold red on the paper. At the same time, we will mark the page number and line number in the main answer. Please see the attachment for the main corrections in the paper and comments on the reviewers.

Author Response File: Author Response.docx

Reviewer 3 Report

The paper discusses and analyses temporal and spatial changes in ET and its potential driving factors in Mongolia over the past 20 years. While this is an interesting topic, there are some issues that need to be further explained and made explicit, in particular the choice of case selection, and the choice of methods, as further explained below.

The title is not clear; what is ET? Please do spell it out.

The abstract seems to be a bit too long, please reduce it.

At the top of page 2, you state that ET has a significant impact on climate change; this is a big claim, which seems to be unsubstantiated. Are you really sure of what you are claiming? Is this a causal relationship or a correlation? How do you measure it? To be honest, I am not convinced.

The methodology section is overall not convincing; the authors describe the study area and the methods, but not why they chose this study area and methods. I believe this is key for the research design of the study; I need to understand why they chose this case study, what type of case study it is, and why those methods. Without this, I cannot validate the findings of this paper. I would therefore suggest a throughout reflection on this issue before proceeding further.

What is the key research question? How does it situate within the relevant literature? Why is it important? What is the literature this paper is contributing to? Why does it even matter, meaning what is the gap to be filled?

 

 

 

 

Author Response

Dear Reviewer:

Thank you for your letter commenting on our manuscript entitled "Temporal and spatial changes in Evapotranspiration and its potential driving factors in Mongolia over the past 20 years" (ID: remotesensing-1592552). At the same time, I would like to thank you for using your valuable time to contribute to our research. These comments are valuable for the modification and improvement of our paper and have important guiding significance for our research. We also appreciate your encouragement and support, which is very important to us. We have carefully studied the comments and corrected them in the hope of approval. The revised part is marked in bold blue in the manuscript. And for the main changes, we marked the specific page number and line number. Please see the attachment for the main corrections in the paper and comments on the reviewers.

Author Response File: Author Response.docx

Round 2

Reviewer 2 Report

The revised manuscript is adequately improved. There are however some remaining minor issues. Please have a look to my minor comments in the attached commented pdf file.

Please also check the language, especially in the newly added text.

Comments for author File: Comments.pdf

Author Response

Dear Reviewer:
We thank again you for your letter commenting on our manuscript entitled "Temporal and spatial changes in Evapotranspiration and its potential driving factors in Mongolia over the past 20 years"(ID: remotesensing-1592552). At the same time, I would like to thank you for making important contributions to our study by spending your valuable time. Furthermore, your detailed and professional comments are very valuable for the modifications and improvements of our paper and have important guiding significance for our research. We also appreciate your encouragement and support, which is very important to us. We have carefully studied the comments and corrected them in the hope of approval. The modified part is marked in red on the paper. At the same time, we will mark the page number and line number in the main answer. Please see the attachment for the main corrections and replies to the comments of the reviewers.

Thank you again for your support and encouragement.

Author Response File: Author Response.docx