Spatiotemporal Analysis of Available Freshwater Resources in Watersheds Across Northern New Jersey
Round 1
Reviewer 1 Report
Comments and Suggestions for Authors
This study analyzes groundwater data in Northern New Jersey to assess freshwater availability using geostatistical modeling. Kriging interpolation and semivariogram models predict spatial variations in salinity, with specific conductance as a proxy. Results indicate a decline in freshwater coverage, especially in the Northeast, due to anthropogenic activities like land use changes and road salt application. The study underscores the impact of human activities on groundwater quality, emphasizing the need for monitoring and management. One weakness of the present manuscript is the lack of novelty in methodology. Further, the manuscript emphasizes limited studies focusing on the selected case study as a novelty, which could make it more appropriate as a case study paper. However, the decision in this regard will be up to the editor. Despite this concern, I recommended the following comments to be considered in the revision stage as follows:
1. Prediction is not an appropriate term for interpolating a variable.
2. The final paragraph of the introduction is too long. Similar problems can be found in other sections.
3. Praising your results with the phrase "valuable" does not seem appropriate in a scientific paper, and the reader must logically conclude that your results are valuable.
4. The information provided in the study area section is not sufficient. The type of aquifer, its boundaries, the location of pumping wells, the direction of groundwater flow, and many other features are not mentioned in the figure and text.
5. Figure 2 must be substantially revised. Now, it is not informative at all.
6. Texts on all figures are not readable at all.
Comments on the Quality of English Language
Grammatical errors exist throughout the text.
Author Response
Please, see uploaded document for response to the reviewer's comments
Author Response File: 
Author Response.pdf
Reviewer 2 Report
Comments and Suggestions for Authors
This study uses kriging interpolation to map salinity changes over time by examining groundwater quality in the Northern New Jersey region. The study analyses groundwater quality data to determine the status of freshwater in the area and specifically highlights the effects of road salts and land use changes on groundwater quality. The authors noted that the kriging interpolation analyses show trends in water quality over time in different residential areas and how they relate to anthropogenic factors, especially urban areas and snowmelt salts.
Comments:
- Axis titles and scales are not visible in the figures. Their quality needs to be improved.
- There are errors in the selection of performance metrics used in evaluating the method. MSE, RMSSE, and RMSE are criteria that are the square or square root of each other. Calculating different metrics, such as MAPE and R2, should demonstrate the model's success.
- It is stated in the abstract that “mean error (ME)” is used. However, this performance metric is not included in Table 2.
- Why were 4 time cycles (cycle 1: 1999 – 2004, cycle 2: 2004 – 2008, cycle 3: 2009 – 2013 and cycle 4: 2014 – 2016) determined in this way?
- A legend should be added to Figure 6.
- The ranges of the vertical axes in Figure 7 should be changed to make the graphs look more detailed. In this way, the differences between the two data will be understood more clearly.
- Ordinary kriging was preferred for Spatiotemporal Analysis. It is recommended to compare the results of other methods. The fact that the spatial analysis techniques of interpolation techniques are different and that features such as elevation affect the estimates reveal the necessity of examining other methods and comparing their results. Providing two references for the method used is insufficient to represent that this method is successful.
- Information such as the amount of data for the data set obtained from wells should be provided.
Author Response
Please, see uploaded document for response to the reviewer's comments
Author Response File: Author Response.pdf
Reviewer 3 Report
Comments and Suggestions for Authors
Values emphasizing the most important conclusions should be added to the abstract.
In line 41, the appropriate designations for the listed ions should be added.
In line 61, you can use the designation 'Na+' instead of 'sodium ions'.
In line 64 the compound 'sodium chloride' appears and in line 68 the designation 'NaCl', pay attention to the first insertion of abbreviations and their explanation in the text.
Paragraph (lines 94-103) for what purpose such a part of the introduction was inserted. Why is there no literature?
In line 109 the abbreviation 'WMAs' appears for the first time, the full name should be given before and the abbreviation™ should be placed in brackets. Please note the introduction of abbreviations throughout the prepared manuscript.
In the last paragraph of the Introduction, there are several threads mixed up. It should be divided into two, one describing the possibilities of using GIS programs and interpolation methods, and the other referring to the purpose of the spatial analyses performed in this article and what new it introduces to the world of science.
If the designations for eleven WMAs are given in lines 145-150, they should be used from this point on, it is not necessary to duplicate the names in brackets in lines 158-159, they should be removed.
Why is it indicated in lines 166-167 the use of data from item [46] and in the caption of Figure 1 it is stated that the land use was developed on the basis of Watt [41].
In Figure 1, the style of the added legends should be standardized for individual parts of the map, whether titles are needed for these two parts. A caption of the figure with parts a and b highlighting should be sufficient.
Lines 179-180 give data collection cycles, whether cycle 1 lasts until 2004 or should end in 2003 as a five-year cycle.
In lines 194-195, the programs used are indicated, the version and producer of the programs should be given.
Figure 2 needs to be refined, this is to show a brief idea of the methodology used, in this version it does not make sense. This should definitely be improved.
Lines 301-303 contain full names and markings of the statistical calculations used, which are partially indicated in the abstract in lines 15-16. Repeats must be removed.
Why is the highway sometimes written with a lowercase or uppercase letter, e.g. line 65, 110, 111, 510.
Can Figures 4, 5 and 7 not be included in the supplementary materials to the article? Now the graphs shown in this way are too small, it is difficult to determine how the axes are signed. And focus in the article on other figures such as 6, 8 or 9.
Is the verification for selected control points in selected cycles I-IV for the krining interpolation taken into account? How were the boundaries of transitions verified between the determined salinity levels, mainly at 750 μS/cm?
Figure 9 requires an improvement in resolution.
Combining the chapter results and discussion, needs to improve the discussion section, both for the results and the application of the chosen interpolation method.
The conclusions chapter needs to indicate the specific results obtained, it is too general.
Author Response
Please, see uploaded document for response to the reviewer's comments
Author Response File: Author Response.pdf
Round 2
Reviewer 2 Report
Comments and Suggestions for Authors
The evaluations given by me have been taken into consideration and met by the authors.
Author Response
Thank you! We appreciate your effort and time taken to review this manuscript.
Reviewer 3 Report
Comments and Suggestions for Authors
There is a significant disparity in the article between the discussion and the results presented. The authors should discuss the results and how they are interpreted in the perspective of previous studies and working hypotheses.
Comments on the Quality of English Language
Some of the wording used in the manuscript should be checked for accuracy. Otherwise, the article is written in the correct language.
Author Response
We sincerely appreciate the reviewer’s insightful feedback on the manuscript. We have expanded the Results and Discussion section to include a new section 3.4.1 - Groundwater Salinization Patterns in Northern New Jersey. This newly added section provides more perspective on previous studies.
