Framework to Study the Effects of Climate Change on Vulnerability of Ecosystems and Societies: Case Study of Nitrates in Drinking Water in Southern Finland

Round 1

Reviewer 1 Report

The article “Framework to study the effects of climate change on vulnerability of ecosystems and societies: Case study of nitrates in drinking water in Central Finland” evaluates the consequences of the climate change to the composition of the ground water.

The authors cover the issue adequately, However, the article needs some minor changes, concerning its style.

Line 13,41,48,53,56,73,79,295,304,418: Replace NO3 with NO₃

Line 20: Replace NO# with NO₃ and NO3 with NO₃

Line 46: Replace mg l-1 with mg/l I think is better

Line 61,219,275,533: Replace CO2 with CO₂

Line 101: 25*25 use symbol × (25×25)

Line 154: the paragraph is repeated

Line 170: the paragraph is repeated

Line 254: “The model estimates canopy photosynthesis and evapotranspiration from daily environmental drivers and stand properties.” I cannot understand the meaning of the sentence

References: Please modify the references according the instructions of the template

Author Response

We corrected all minor comments, especially lower and upper cases in abbreviations.  

PREBAS model was described in more detailed on Lines 233-248 

Reviewer 2 Report

I find you work very intersting, dealing with an important issue fo the future. Although the interesting topic and the methodology used, the overall presentation level of the paper is in low. However, due to the fact that the paper is interesting and the background of the methodology sound, I would suggest a major revision, for the authors to have the time to improve the manuscript. Their work need to be better presented.

Some specific points:

Figure 1: Please provide a more refined version of your map, it is not clear what the numbers on the map represent. Also, the subclasses are odd, e.g. you have 2 grey ones that cannot be differentiated. Finally, the term “groundwater aquifers” is not appropriate, I would suggest the term “aquifers”

Figure 2: If it is possible, provide this graph with different colors for each case to make it easier for the reader to differentiate

Figure 3: Since there is some connection between the models you could maybe highlight those by using a flow graph or any other graphical option you would prefer. Also, for the INCA model the output I missing

Figures 4, 5 and 6, please provide clearer and/or larger graphs

Structural points

L42-45 I find this somehow irrelevant to the rest of the study, especially since you also make the statement in L57

The section “Discharge, water quality and meteorological data” has been introduced 2 times, in L113 and L154, the text is exactly the same so just delete either one of them

As mentioned above, for the section “Phenological development of vegetation cover, and timing of snow melt” in L129 and L170

I would highly recommend adding some maps so that the reader can have a better understanding of the study area. I would really like to see a map with all the monitoring points (meteo data, discharge data etc), which could also possibly be combined with Figure 1. The same applies to Table 1, maybe it would be better to visually present this data. Being a little more creative with this can add a lot to your paper. An good example for that is that, when someone reads through L278-283 has no idea about where those points you are referring to are

The whole Conclusions section needs improvement, please elaborate a little bit more on the main outputs of your study

Scientific points

One of the interesting aspects of your work is that you take into account the fact that ecosystems have defensive mechanisms to changes (e.g. climate). This is usually overseen from individuals that feel the need to emphasize on the (unquestionable) negative impact of climate change

For all the things mentioned between L291-307, first of all, this part clearly belongs to the results section. In addition, I find it inconvenient that you are presenting half of the results in decimal numbers and in percentage, while you are also using NSE and R2 values, which can be misleading since you have to think 2 times to get it right and this can cause confusion to the reader. I would prefer to have one of those for all results. Finally, I find that you have set the bar relatively low, with a good example of that being the NSE in the validation period. This means that you might actually need to go back and reconsider even the conceptual model that is the base of your mathematical model. 

I would really like to see a comment on the data. The fact that you are using a lot of data is certainly positive, with data availability apparently not being an issue in your case. However, I would like to have some further information on whether you had to filter the data, omit some of them, have you used weights, what is the level of confidence, would you think that your methodology is widely applicable regardless the fact that it needs a lot of data, is the increased complexity handled appropriately by the model or there is some information lost etc

Author Response

Answers to Reviewers

Minor comments:

We corrected all minor comments, especially lower and upper cases in abbreviations. We also improved quality of the figures and redraw the map. We decided not to include scenario names in the figures 7-10, because they became very difficult to read. The ‘area’ that different scenarios cover is interesting, but none of the scenarios represent ‘the truth’.

Data:

Almost all data is available in open data bases of SYKE, LUKE and FMI. That data is also quality checked in sampling and analysis phases, before it is open. Only interview data of farmers is not open, but summaries of interviews are published. Data and how it was handled in the modelling process are described in more detail on Lines 115-140. 

Calibration:

Calibration and validation improved considerably, when input data from two meteorological stations were used.

Hydrological calibration was ‘satisfactory’, probably because of elevation difference between catchment and meteorological stations. In addition, small catchment Mustajoki responded fast to small and sharp summer rains, which were not recorded at the meteorological station. In this work focus is in nitrate concentration, which was ‘very good’, except in one catchment, where it was ‘satisfactory’. NH₄ calibration failed in one catchment. The reason seems to be that our statistics and method to estimate emissions from houses outside municipal sewage system is old and insufficient.

Calibration/validation part was moved to Results section. Only PBIAS value is reported, as it is a measure of the (concentration) level that is easy to interpret (0 is the best value). Lines 307-321, and 290-304.

Flow chart of models was added to the manuscript (Figure 3) and flow chart of data was modified (Figure 4). Page 9 

Discussion:

We improved the discussion section.

Good data is valuable to understand the processes that we are modelling. Good data is needed in calibration/validation of the models, but we can substitute missing data at some level by using literature values. Interpretation of the simulations to results should then be in line with data quality. All models, if they are well-enough calibrated, can be relatively well moved to other areas or to upscaled lo larger areas. Lines 397-408. 

Round 2

Reviewer 2 Report

Sections 2.1.2 and 2.1.3 have the same title (Discharge, water quality and meteorological data)

The resolution in Figure 1 is not very good, if you would please provide the same Fig in higher resolution

Figure 6 is used as caption 2 times

Figures 5-8 are very blurry. Since your paper is not so long I strongly suggest that you make them slightly larger and in color

I would still suggest that you make a more collaborative Conclusion

Author Response

Sections 2.1.2 and 2.1.3 have the same title (Discharge, water quality and meteorological data)

That is corrected.

The resolution in Figure 1 is not very good, if you would please provide the same Fig in higher resolution

I improved resolution. If that is not enough, I have still capacity to improve it.

Figure 6 is used as caption 2 times

Corrected

Figures 5-8 are very blurry. Since your paper is not so long I strongly suggest that you make them slightly larger and in color

These are now in color, and exposure and vulnerability figures were partly redrawn.

I would still suggest that you make a more collaborative Conclusion

I tried to improve it. Also discussion has some changes and one new reference.