Pseudo-Spatially-Distributed Modeling of Water Balance Components in the Free State of Saxony

Round 1

Reviewer 1 Report

Accept for publication

Author Response

Dear Reviewer,

Thank you very much for your suggestion. As suggested, the manuscript was sent for  language editing and proofreading. The corrections can be seen in the manuscript.

Best regards,

Luong, Thanh Thi

Author Response File: Author Response.docx

Reviewer 2 Report

The paper describes the application of the physically based lumped-parameter water balance model BROOK90 for the estimation of water budget components for catchments in the Free State of Saxony (Germany). The authors used the hydro response units (HRUs) approach with commonly available data for soil, vegetation and meteorology of different sources. The results were validated with observed daily and monthly discharge data as well as evapotranspiration and soil moisture data of a freely available remote sensing product of 10 headwater catchments.

The paper is well structured and written. All steps are described clearly and can be reproduced. Tables and Figures are clear and illustrate the intermediate steps and results. The conclusions and the outlook are logic and understandable. There are only small points of criticism. First, such studies are not really new. In the context of rainfall runoff modelling similar studies were already presented in many papers. This is an interesting case study. But I cannot find new methodological aspects. Second, in the paragraph from line 403 to 417 the authors write about “trends” and “significant or not significant differences”. I could not find any statistical tests confirming this. It would be good if they can add some things in this context.

Despite this small flaws, I recommend the acceptation of the paper with minor correction.

Author Response

Dear Reviewer,

Thank you very much for your comments and suggestion for improving the manuscript. Your comments have been worked out and changed accordingly in the manuscript. Please find the detail responses in the attachment.

 

Best regards,

Luong, Thanh Thi

 

Author Response File: Author Response.docx

Reviewer 3 Report

Thank you for the opportunity of being one of the first reader of the paper. It is very interesting, valuable.I really like the way you stated the thesis in the Introduction part.The quality of figures is well. I have noticed great insight in analyzing the available literature, it is international and up-to-date. I miss only small things. In a text elements, where figures and/or tables are discusses I miss reference to specific numerical values, like line 425, page 14: the highest variations in term of B.... (please add values);line 326, page 11: Modeled and observed Q vales matched well on the seasonal .... (maybe it would be good to add KGE specific value)  --> such analyses I found in many parts of the paper, it would be easier to read if I have a specific values: now I had to look for it in a table or in the picture while reading.

Author Response

Dear Reviewer,

 

Thank you very much for your interest toward the paper and the suggestion to improve its readability. Your comments have been taken into account and changed accordingly in the revised manuscript. Please find the detail responses in the attachment.

 

Best regards,

Luong, Thanh Thi

Author Response File: Author Response.docx

Reviewer 4 Report

The paper describes application of the BROOK90 model to 10 catchments in the Saxony region to estimate outflow (Q), evapotranspiration (ET) and soil moisture (SM). The input data needed for the modelling was collected from various sources and is of different quality (in terms of spatial and temporal resolution).

To run the model, the input data was somewhat simplified: CORINE 2012 was reclassified into fewer classes as well as the soil map (reclassified according to the USDA classification). Both datasets were used to delineate HRUs. However, I am lacking the information on incorporating topography as an important parameter in defining HRUs. It seems that only land use and soil map were overlayed to create HRU map. What is the resolution of the HRU data?

Line 247-255: From wich time period the data was collected?

Line 275 - Figure 4: It would be useful to overlay the map with the boundaries of the chosen catchment. It seems that some catchments overlap with the areas where model could not perform properly.

Line 285: How was Q estimated (simulated Q)?

Line 297: Grid cell size of the SMAP_L4_GPH is 9*9 km, cells illustrated on the Fig.4(e) map are not 9*9

It would be useful to comment on data gaps of SM and ET as they are visible in Figure 5 (monthly SM and ET) (Observed/SMAP).

How did the authors deal with running the model in the catchments that contain the pixels in which the model is not applicable or could not perfom (as shown in Figure 4)?

Could you comment on low corelation coefficient for the daily flows for catchemnts 1, 2, 7, 9 (Figure 6)?

Author Response

Dear Reviewer,

Thank you very much for your comments and questions, which point out the core of the study as an attempt to simulate water balance components at high resolution. Please kindly find my responses in the attachment!

 

Thank you very much for your remarks regarding the language. The manuscript was sent for language editing and proofreading by native-speaker.

Best regards,

Luong, Thanh Thi

 

Author Response File: Author Response.docx