Dear Authors,

Thank you very much for your extensive revisions and replies to the comments made during the review process. I have been through them all and I think the context and focus of the paper makes this broadly relevant to other modellers, and I am happy to see this go forward for publication now.

However, after reading I did pick up a lot of minor editorial issues, that I would like you to go through and spend some time fixing up before final approval. I have not gone through an made a point by point list but ask you to carefully proof read the english and expression. For example:
* I dont think the word "managerial" is appropriate in this context
* At the end of the abstract, may be better if you say "aquatic system modelling" rather than ecosystem, since this is a hydrology journal
* "Specifcally, the case study's goal" - I think this should be reworded, so that the aim of this paper is described, not the aim of the case study. (Case study is a way to get to the aim)
* Sentence 2 of introduction - wrong use of "for" - reword.
* Paragraph 2 of intro - First sentence should start with a "The ..."

There are many small things like this throughout - can you please go through and do a rigorous check and then re-upload a final version?

Kind Regards
Matt Hipsey

Dear Koji

Thankyou for the revision. My apologies to further prolong the acceptance of this manuscript which I think is a nice contribution, however, I highlight still many errors, albeit minor, and so would like to see these looked at to ensure the readability is as good as possible - suggestions below.

Title: I think it should be "forcing" rather than "forcings"

Abstract:
"cancel the costly management effort" should in my view be "cancel management efforts" (I don't think costly helps"

"because a favourable stochastic event overestimates success of the management effort" could be better worded as:
"because a favourable stochastic event may overestimate the perceived success of the management effort"

line 11 "nutriend" instead of "nutrient loading" is written

"is not limited to lake water quality studies and therefore
should provide certain utility in other types of ... "
could be more succinct as:
"is not limited to lake water quality studies and may also provide utility in other types of ... "

Introduction:

Line 3 could be : “Such is the case in the context of reducing nutrient loads for the purpose of improving the water quality of downstream lake environments.”
“by counteracting the abatement of nutrient loading ” better as: “by counteracting any positive benefits derived from the abatement”
Also - could this statement be referenced with an example?

Line 11: “modelling method could disentangle” better as: “modelling method is able to disentangle …”

Line 26: “Increase” should be “An increase …”

Line 21: “due to the stochastic dynamics of lake’s response to weather,” should be : “due to the dynamics of a lake’s response to stochastic nature of weather,
I don't think you mean the lake dynamics (mixing, biogeochemistry) are stochastic, so reworded to highlight it is stoichatsic forcing you are referring to.

Liune 22: I don't think it is clear to say “one of the lake models” as you have not previously referred to any… also “based on system” needs an “a”

“some forcing data being FROM the actual records, and”

“criss-cross” should be replaced with “inter-weaves” or a similar descriptive word

“avarage” should be average

“Combinations of these two types of forcing data are described in Sect. 2.5” - this para is really crossing into methodology, and comes before the aims. The reader should not be referred to a section before the aim and purpose fo the paper is clear. Please just look to be careful the introduction remains pure from getting into details, and simply builds the argument and motivation for addressing the aim.
Similarly the sentence after this one to the end of the paragraph is bordering on discussion since you are highlighting benefits of this approach (which the reader has not seen by this stage)

“change impacts on THE physical landscape “

“We also visually inspect “ … remove also

“ (3) the predicted lake responses were compared among different scenarios, in particular, the variance among years, rather than the absolute value of the predictions.”
I get this but still find it a bit unclear and I think other readers may be confused by this.

“Six variables including THE whole-lake average TP pool “

“for THE scenario experimentS described below.”

“water temperature profile was”
should be “water temperature profiles were”

“We deployed the Markov “ should be “We employed the Markov “

“full actual forcing data elucidates THE importance”

“which output variables WERE most reduced “

Page 10: “despite such wind events may be crucial “ should be: “despite such wind events being crucial “

“or determination of THE thermocline “

“most average looking yearS”

“variAtions or incoNsistencies

The results and discussion seem to read much better!

I look forward to seeing the final version.
Regards
Matt

Dear Authors
Thank you for the prompt update to the manuscript, I think most issues are resolved and it now seems to read much more easily.
One final set of minor points:
Page 4: "Here we used one of lake models ..."
"Here we used one of the lake models ..." ??
Page 5: I dont think you need to repeat the Saloranta ref again in the aim

I am therefore happy to now see this accepted and move to final publication with HESS.

Thank you for your contribution, and best wishes for your ongoing research.
Regards
Matt Hipsey