PONE-D-20-14901

Simulating possible Impacts of climate variability and change on Maize production in Embu County, Kenya

PLOS ONE

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Additional Editor Comments (if provided):

Please see the reviewers' comments. Both the reviewers find the article interesting. However, both think major revisions are required before publication. Particularly, first reviewer is very critical. Authors need to address all the comments of both the reviewers.

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Reviewers' comments:

Reviewer's Responses to Questions

Comments to the Author

1. Is the manuscript technically sound, and do the data support the conclusions?

The manuscript must describe a technically sound piece of scientific research with data that supports the conclusions. Experiments must have been conducted rigorously, with appropriate controls, replication, and sample sizes. The conclusions must be drawn appropriately based on the data presented.

Reviewer #1: Partly

Reviewer #2: Yes

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2. Has the statistical analysis been performed appropriately and rigorously?

Reviewer #1: No

Reviewer #2: Yes

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Reviewer #1: Yes

Reviewer #2: No

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Reviewer #1: Yes

Reviewer #2: Yes

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5. Review Comments to the Author

Please use the space provided to explain your answers to the questions above. You may also include additional comments for the author, including concerns about dual publication, research ethics, or publication ethics. (Please upload your review as an attachment if it exceeds 20,000 characters)

Reviewer #1: General Comments

This is an interesting article assessing the impacts of climate change on growth and performance of maize using DSSAT and APSIM under RCP4.5/RCP8.5 at the mid and end century. However, the article can be improved by having a reduce and proper structure (section and sub-section) and headings. Some of the section/sub-section was found to be too general and not specific (can be combine with other sub-section) with the research title and objectives. Many sub-section and paragraph was found to be repetitive and redundant. It is preferable to have a sub-section with a heading directly discussing the objectives of the study.

I would strongly advice that a proper step by step procedure on the methodology involved should be prepare to clarify how the objectives was achieved. It was difficult to get a clear picture of the future projection (Tmin, Tmax and Prec) for the study because the authors are employed the 20 GCMs individually. The methodology can be improved by using an ensemble of GCMs, instead of using individual GCMs which introduce a lot of uncertainty in your final output. I would advise the authors to make an ensemble of the 20 GCMs or make an ensemble of the selected GCMs which can better modulate the local climate. Otherwise, the future projection output will have a big uncertainty, confusing and meaningless. The high uncertainty in the output, where some GCMs give positive results, while other GCMs give negative results, would render the results to meaningless as it seems unreliable to at least predict a certain degree of certainty in the future. It is understandable that different GCMs will have its own inherent variability. Therefore, an ensemble methodology should be use to reduce such uncertainty.

It is not clear how the authors get the results for certain output, either through individual GCMs or taking a mean based on 20 GCMs (it should be ensemble, not mean). Due to lack of clarity in the methodology involved in getting the final output of certain section/sub-section, the authors seem to be confuse about what it means by GCM ‘ensemble’.

It would be a major change in the results/output of the research if a proper ensemble method or any method selecting the best GCMs was applied, instead of using 20 individual GCMs (which introduce high uncertainties). I would advise for major revision of the article at its current state because without improve methodology, there will be a high uncertainty in the result/output of this article. Other specific comments can be found below.

Specific comments

Abstract:

• Line 9: Website link address can be insert at the Materials and Methods section

• Line 11: It then develops an adaptation strategy that is locally > Then, adaptation strategy was develop that is locally...

• Line 12: that help offset > to offset

• Line 15: but differed in the magnitude of that increase > with different magnitude

• Line 16: higher and those by CanESM2 > higher than CanESM2, INMCM4 and NorESM1-M under both emission scenarios.

• Line 18: abbreviations for minimum temperature (Tmin) and maximum temperature (Tmax) can be use here. Please change for the rest of the manuscript.

• Line 24-27: This sentences is too long to be in the abstract and confusing. What is the meaning of 'short duration varieties' and 'long duration varieties'? Do you mean ‘short duration maize varieties’…?

• Line 34: at national and local levels and make their promotion easier > at national and local level.

• Line 35-38: This sentence is too long. Need to be rephrase and simplify.

Introduction

• Line 57: plant available water? Is this a scientific term?

• Line 107: are viable is required > are viable.

• Line 122: to adapt to the same > for adaptation

• Line 124-126: Developing downscaled location specific climate change scenarios > Downscaling site specific climate change scenarios for various agro-ecological zones (AEZs) of Embu county in Kenya under RCP4.5 and RCP8.5 at the mid and end century period.

• Line 127: on the performance of maize > on maize yields

• Line 128: and to identify key vulnerabilities? What do you mean here? To identify vulnerable area or to identify vulnerability factor?

• Line 129: the objective is for a general agricultural systems or specific to maize agricultural system?

Materials and Methods

Study Location

• Line 157: potential area for what? agriculture? which crop?

• Line 161: do you mean long duration maize varieties?

Crop data and model parameterization

• Line 241: required data > the required data

• Line 248: and the same were derived from the data collected > and the same data was collected...

• Line 249: were derived from the amount > were based on the amount

• Line 265: NO3 and NH4 > NO3 and NH4

• Line 267: 50 mm and 0.75 m

Results

Observed trends in climate

• Line 278: also in the temperatures > also in the precipitation

Projected changes in future climate

• Line 326: for the crops grown in that AEZ > for the crops grown in the study area.

• Line 341: I think there is a major difference as well between SR and LR season under RCP4.5 although the difference under RCP8.5 is bigger.

Impacts of climate change on maize yields

• Line 389: to mid and end century > at the mid and end century

• Line 403-405: This sentence is redundant. Please remove.

• Line 406-412: It is better to have an ensemble of future projection to reduce the uncertainty rather than using and discussing each individual GCMs which could entail lengthy and contradictory results.

• Line 415-: How did you get the exact percentage result here? Previously, you discuss that there is a range of output by different 20 GCMs being used. You should not take the mean of the output from each GCMs here. Only an ensemble can do.

Effect of management on climate change impacts on maize yields

• Line 429: the effect of variety > the effect of maize variety

• Line 434-: The different and contradictory result might be due to the usage of 20 GCMs individually, instead of using an ensemble of GCMs. This might be the source of high uncertainty in your output by APSIM and DSSAT.

• Line 442: simulation analysis > simulation analysis,

• Line 477: What daoes it means by early planted maize? Can you specify the exact date and duration here?

Impacts under elevated carbon dioxide levels

• Line 493: It is better to have an ensemble of GCMs, rather than individual GCMs result as it will introduce high model uncertainty in your DSSAT and APSIM modelled yields.

Adaptation strategies

• Line 510: performing variety > performing maize variety

• Line 535: which propose intervention do you mean here?

Discussion

• The first paragraph is just a general statement and can be remove or relevantly insert at various part of other section/sub-section.

• Line 552: effectiveness > the effectiveness

Climate variability and change

• This sub-section is too general and doesn't reflect with the research title and doesn't reflect with the research objectives on maize yields. It is better to directly integrate the results being obtained here and relate it with other relevant sub-section which reflect your main findings (related to maize yield).

• The first paragraph is redundant. It is better to directly discuss your results.

• The second paragraph should be discuss in data section

• Line 594: Daily Temperature Range (DTR) > Diurnal Temperature Rang (DTR)

• Line 611: 'we used an ensemble of 20 GCMs' > This statement is confusing with your previous methodology and discussion. Are you using GCMs individually or an ensemble of GCMs? The author should have a proper understanding of what 'ensemble' means.

• Line 612-613: This statement should be discuss in the methods and data section. The reason for selecting only two different emission scenario (RCP4.5 and RCP8.5) and two time period (mid and end century) should be properly justify.

• Line 615-: This section should be in the methods section. It is repetitive.

Impacts of climate variability and change on maize production

• The statement in the first paragraph is general making it lengthy. It should directly discuss the sub-section topic on 'Impacts of climate variability and change on maize production'

Conclusions

• The first paragraph is redundant and repetitive from previous section. It should be remove.

• Line 745: This is the first time that 'multi-model ensemble' being mention, and it was mention at the conclusion. This is confusing. Your results discuss individual GCMs, not an ensemble of GCMs. Please clarify.

• Line 763-: The specific discussion and specific results for the intervention (changing variety, plant density, soil fertility management etc.) are scatter across the article and not properly and directly discuss in sub-section ‘Adaptation strategies’. It is difficult to understand how these interventions play a key role in maize production in relation with climate change impact.

Reviewer #2: The manuscript presents an approach to assess the climate change impact on Maize production, which is interesting. The subject addressed is within the scope of the journal; however, the manuscript, in its present form, contains several weaknesses. Appropriate revisions to the following points should be undertaken to justify the recommendation for publication. So, I suggest that this manuscript should be revised as major revision.

Abstract:

1- L9: Eliminate “(www.agmip.org)”.

2- There are mixed verb tenses, somewhere use the present tense “L8: The study assesses…..”, and other places use the past tense, “L12: The study used…”. Please use the present or past tense in the whole of the paper.

3- Please rewrite lines 13 to 15.

4- It would be better to highlight your contribution, more clearly in abstract.

Introduction:

5- The authors should highlight the research significant, more clearly in the introduction section.

6- There are some grammatical errors in this section. Please check whole the section carefully.

7- References are not always relevant and up-to-date. This reviewer suggests the inclusion of a few relevant publications. The list is given below:

https://rmets.onlinelibrary.wiley.com/doi/abs/10.1002/joc.6307

https://link.springer.com/article/10.1007/s11368-020-02632-0

https://link.springer.com/article/10.1007/s00704-019-02979-6

https://www.sciencedirect.com/science/article/pii/S0168192319302199

Method:

8- It is mentioned in L133 that the Embu County in Kenya is adopted as the case study. What are other feasible alternatives? What are the advantages of adopting this particular case study over others in this case? How will this affect the results? The authors should provide more details on this

9- It is mentioned in L181 that historical records of 1980 to 2010 are taken. Why are more recent data not included in the study? Is there any difficulty in obtaining more recent data? Are there any changes to the situation in recent years? What are its effects on the result?

Results and discussion

10- From Figure 6, it is evident that the authors obtained poor performance (R2: 0.33-0.44) during the validation phase. Is it a reliable model for crop simulating?

Conclusion

11- In the conclusion section, the limitations of this study suggested improvements in this work, and future directions should be highlighted.

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Reviewer #1: Yes: Zulfaqar Sa'adi

Reviewer #2: No

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Attachments

Attachment

Submitted filename: Comments.docx

PONE-D-20-14901R1

Simulating adaptation strategies to offset potential impacts of climate variability and change on maize yields in Embu County, Kenya

PLOS ONE

Dear Dr. Gummadi,

Thank you for submitting your manuscript to PLOS ONE. After careful consideration, we feel that it has merit but does not fully meet PLOS ONE’s publication criteria as it currently stands. Therefore, we invite you to submit a revised version of the manuscript that addresses the points raised during the review process.

Please submit your revised manuscript by Oct 23 2020 11:59PM. If you will need more time than this to complete your revisions, please reply to this message or contact the journal office at plosone@plos.org. When you're ready to submit your revision, log on to https://www.editorialmanager.com/pone/ and select the 'Submissions Needing Revision' folder to locate your manuscript file.

Please include the following items when submitting your revised manuscript:

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• An unmarked version of your revised paper without tracked changes. You should upload this as a separate file labeled 'Manuscript'.

If you would like to make changes to your financial disclosure, please include your updated statement in your cover letter. Guidelines for resubmitting your figure files are available below the reviewer comments at the end of this letter.

If applicable, we recommend that you deposit your laboratory protocols in protocols.io to enhance the reproducibility of your results. Protocols.io assigns your protocol its own identifier (DOI) so that it can be cited independently in the future. For instructions see: http://journals.plos.org/plosone/s/submission-guidelines#loc-laboratory-protocols

We look forward to receiving your revised manuscript.

Kind regards,

Shamsuddin Shahid

Academic Editor

PLOS ONE

Additional Editor Comments (if provided):

Reviewer 1 pointed out several specific issues. Authors are requested to revise the article based on the comments.

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Reviewers' comments:

Reviewer's Responses to Questions

Comments to the Author

1. If the authors have adequately addressed your comments raised in a previous round of review and you feel that this manuscript is now acceptable for publication, you may indicate that here to bypass the “Comments to the Author” section, enter your conflict of interest statement in the “Confidential to Editor” section, and submit your "Accept" recommendation.

Reviewer #1: All comments have been addressed

Reviewer #2: All comments have been addressed

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2. Is the manuscript technically sound, and do the data support the conclusions?

The manuscript must describe a technically sound piece of scientific research with data that supports the conclusions. Experiments must have been conducted rigorously, with appropriate controls, replication, and sample sizes. The conclusions must be drawn appropriately based on the data presented.

Reviewer #1: Yes

Reviewer #2: Yes

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3. Has the statistical analysis been performed appropriately and rigorously?

Reviewer #1: No

Reviewer #2: Yes

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4. Have the authors made all data underlying the findings in their manuscript fully available?

The PLOS Data policy requires authors to make all data underlying the findings described in their manuscript fully available without restriction, with rare exception (please refer to the Data Availability Statement in the manuscript PDF file). The data should be provided as part of the manuscript or its supporting information, or deposited to a public repository. For example, in addition to summary statistics, the data points behind means, medians and variance measures should be available. If there are restrictions on publicly sharing data—e.g. participant privacy or use of data from a third party—those must be specified.

Reviewer #1: Yes

Reviewer #2: No

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5. Is the manuscript presented in an intelligible fashion and written in standard English?

PLOS ONE does not copyedit accepted manuscripts, so the language in submitted articles must be clear, correct, and unambiguous. Any typographical or grammatical errors should be corrected at revision, so please note any specific errors here.

Reviewer #1: Yes

Reviewer #2: Yes

**********

6. Review Comments to the Author

Please use the space provided to explain your answers to the questions above. You may also include additional comments for the author, including concerns about dual publication, research ethics, or publication ethics. (Please upload your review as an attachment if it exceeds 20,000 characters)

Reviewer #1: General Comments

The manuscript has been greatly improved by the authors after the first revision. However, there is still few improvements on the arrangement of the section/sub-section that can be done (refer to the specific comments). In term of methodology, although the authors have reply properly the comments given, some of it wasn’t inserted into the manuscript (refer to the specific comments). The methods and results are still mixed-up in some of the section/sub-section which the authors can make in a more proper order and sequence. Some clarification on how the future changes was calculated has been reply through peer-review comments but wasn’t mentioned anywhere in the manuscript. There are some minor but substantial details on the results and discussion that need to be revised.

Other specific comments can be found below.

Specific comments

Abstract:

•Line 19: There are 20 GCMs used. Therefore, projection by HadGEM2-CC, HadGEM2-ES, and MIROC-ESM should be higher than the rest of 17 GCMs. Why is it mention here, projection of HadGEM2-CC, HadGEM2-ES, and MIROC-ESM is higher than CanESM2, INMCM4 and NorESM1-M only?

•Line 31: Are you 'develop' the adaptation practices or 'incorporate' the adaptation practices into the model?

•Line 33: I think you are incorporating the operational adaptation strategies using the readily available technologies here, not develop the operational adaptation strategies using the readily available technologies.

Section 1. Introduction

•Line 63: which are > which have a marginal

•Line 63: adding to this > adding to this,

•Line 125: Instead of using the term climate, a more specific term, rainfall, Tmin, Tmax (climate indices that you assess) should be mention here. Climate can be a lot of things.

•Line 127: Repeated abbreviation for AEZs

•Line 127: various AEZs, namely,... > the zones used in the study should be mentioned here.

•Line 130: Are you developing adaptation options?

Section 2.1 Study Location

•Line 141: rising > up to

•Line 157: AEZs > AEZs of

•Line 163: higher use > higher application

2.2 Assessing current climate variability and future climate conditions

•Line 166: Assessing? Are you making any assessment here? There is no discussion on the assessment of current climate variability in this sub-section. The heading is confusing.

•Line 181: Please be notify that the font size is different here. Please check throughout the manuscript.

•Line 190: pathway are > pathway

•Line 193-196: The equation number for equation (1)-(4) should be align right and the equation should be centre.

Section 2.3

•Line 234: I don't think you need to give this heading. Sub-heading 2.31 can be change to sub-heading 2.3

2.3.1 Crop Simulation Models (CSMs)

•Line 241: were used to assess > to assess

•Line 246: Please recheck if there is any more repetitive abbreviation throughout the manuscript.

2.3.2 Model parameterization

•255: Sub-heading 2.3.2 can be change to 2.4. While sub-section Farm and farm management data can be change to 2.4.1 etc for the rest of sub-heading.

Farm and farm management data:

•Line 271-276: Please re-phrase this sentence.

•Line 281: During In the survey > During the survey

•Line 283: This formed?

Model calibration and validation:

•Line 312-323: This discussion should be put into results or discussion section.

Crop simulations:

•Line 332: NO3, NH4 > NO3, NH4

•Line 337: and or > and

•Line 342: crop simulation model > CSM

3. Results

•There should be a sub-section under Results to discuss the performance of APSIM and DSSAT in term of calibration and validation of the model.

3.1 Trends in observed climatic conditions

•Line 359: How do you measure the trend? Simple Linear Regression?

•Line 360: delete 'and in the rate of increase'

•Line 361: Why are you comparing Tmax and Tmin for period 2001-2010 with period 1981-1990? You can make a simple regression line to see the increasing rate of Tmin/Tmax from the whole historical period of 1981-2010.

•Line 367: If you are using simple linear regression for trend, you can give the increasing/decreasing rate here.

•Line 373-378: You discuss the results in the previous paragraph. Only now, you discuss the method that you use. This is not in proper order. Also, please give briefly the method that you use for trend analysis in the method section. Not in results section.

3.2 Projected changes in climate conditions

•Line 380: surface temperature > use directly the specific temperature indice that you employ, Tmin and Tmax. Surface temperature can be a lot of things.

•Line 385: You are employing 20 GCMs, but these 4 GCMs (HadGEM2-CC, HadGEM2-ES, IPSL-CM5A-MR, IPSL-CM5A-LR) is higher compare to only other 4 GCMs (CanESM2, INMCM4, MRI-CGCM3, and NorESM1-M)? This is confusing.

•Line 388: Projected increase was being compare with which historical period?

•Line 391: Please use a consistent decimal places for temperature throughout the manuscript.

•Line 397: 3.5 oC > 3.5oC, make similar correction throughout the manuscript

•Line 398: Give numerical value for the result and discussion. What is the value for current temperature? What is value for low temperature event? What is value for high temperature event?

•Line 400: sift > shift

Impacts across AEZs:

•This can be sub-heading 3.2.1. Do the same for the rest.

Impacts across seasons:

•Line 447: delete 'DSSAT'

•Line 451: what is the numerical value for baseline yields?

Impacts of plant population:

•Line 496: population > plant population

Impacts of soil fertility and nitrogen application:

•Line 502: How exactly climate change give positive impacts? Increase rainfall/temperature?

3.3 Adaptation strategies

•Line 527: What exactly is adapted technology that you mentioned here?

•Line 531: All of this results discussing about adapted technology? or certain management practice? Please make it clear. In the first paragraph of this section, you are talking about various management practice, then you are talking about adapted technology. Now, the results are talking about which one? This is confusing.

4.1 Assessing variability in the current and projected climatic conditions

•Section 4.1 > This heading is unnecessary

4.1.1 Climate Variability

•Line 567: variability in term of temporal or spatial?

4.2 Impacts of climate variability and change on maize production

•Line 644: was done carried out > was carried out

•Line 659: AEZs > AEZs of

•Line 660: AEZs > AEZs of

4.3 Adapting to climate change

•Line 705: This sub-section seems to be a general statement. May be can briefly incorporate in the conclusion.

Figure 2

•The outside borderline box should be remove. Do the same for all figure except fIg. 1 as the borderline box is require for lat/lon information.

Figure 5

•The Legend can be improve

•Please re-check the font size of the caption

Figure 7

•Please put dot line between AEZs. The series overlap can be made to 0%. Do the same for Fig. 9 as well.

Figure 8

•Series overlap can be made to 0% for each GCM

Table 1

•Table can be improved. No color shading should be use and a proper bordering line should be employ. Please refer to other research article on how to prepare a proper table for research publication. Do the same for all Table.

Reviewer #2: The authors have addressed all of the my comments. So, I suggest to publish the paper in current form.

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Reviewer #1: Yes: Zulfaqar Sa'adi

Reviewer #2: No

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Attachments

Attachment

Submitted filename: Comments.docx

PONE-D-20-14901R2

Simulating adaptation strategies to offset potential impacts of climate variability and change on maize yields in Embu County, Kenya

PLOS ONE

Dear Dr. Gummadi,

Thank you for submitting your manuscript to PLOS ONE. After careful consideration, we feel that it has merit but does not fully meet PLOS ONE’s publication criteria as it currently stands. Therefore, we invite you to submit a revised version of the manuscript that addresses the points raised during the review process.

Please submit your revised manuscript by Nov 15 2020 11:59PM. If you will need more time than this to complete your revisions, please reply to this message or contact the journal office at plosone@plos.org. When you're ready to submit your revision, log on to https://www.editorialmanager.com/pone/ and select the 'Submissions Needing Revision' folder to locate your manuscript file.

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We look forward to receiving your revised manuscript.

Kind regards,

Shamsuddin Shahid

Academic Editor

PLOS ONE

[Note: HTML markup is below. Please do not edit.]

Reviewers' comments:

Reviewer's Responses to Questions

Comments to the Author

1. If the authors have adequately addressed your comments raised in a previous round of review and you feel that this manuscript is now acceptable for publication, you may indicate that here to bypass the “Comments to the Author” section, enter your conflict of interest statement in the “Confidential to Editor” section, and submit your "Accept" recommendation.

Reviewer #1: All comments have been addressed

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2. Is the manuscript technically sound, and do the data support the conclusions?

The manuscript must describe a technically sound piece of scientific research with data that supports the conclusions. Experiments must have been conducted rigorously, with appropriate controls, replication, and sample sizes. The conclusions must be drawn appropriately based on the data presented.

Reviewer #1: Yes

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3. Has the statistical analysis been performed appropriately and rigorously?

Reviewer #1: Yes

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4. Have the authors made all data underlying the findings in their manuscript fully available?

The PLOS Data policy requires authors to make all data underlying the findings described in their manuscript fully available without restriction, with rare exception (please refer to the Data Availability Statement in the manuscript PDF file). The data should be provided as part of the manuscript or its supporting information, or deposited to a public repository. For example, in addition to summary statistics, the data points behind means, medians and variance measures should be available. If there are restrictions on publicly sharing data—e.g. participant privacy or use of data from a third party—those must be specified.

Reviewer #1: No

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5. Is the manuscript presented in an intelligible fashion and written in standard English?

PLOS ONE does not copyedit accepted manuscripts, so the language in submitted articles must be clear, correct, and unambiguous. Any typographical or grammatical errors should be corrected at revision, so please note any specific errors here.

Reviewer #1: Yes

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6. Review Comments to the Author

Please use the space provided to explain your answers to the questions above. You may also include additional comments for the author, including concerns about dual publication, research ethics, or publication ethics. (Please upload your review as an attachment if it exceeds 20,000 characters)

Reviewer #1: General Comments

The manuscript has been greatly improved by the authors since the first revision. The manuscript section/sub-section has been arranged in a good order. There are some minor revision needed, given in the specific comments below.

Specific comments

Abstract:

•Line 20: than rest > than the rest

1.Introduction

•Line 78: projected climate conditions > projected climate conditions on crop growth

•Line 126: maximum and minimum temperatures > Tmax and Tmin

2.2 Current climate variability and future climate conditions

•Line 172: All of the four stations > All stations

•Line 198: Representative Concentration Pathways (RCPs) > RCPs

•Line 200: W m−2 > W m-2

•Line 209: Arrange the equation properly

•Line 227: as use > the usage

•Line 234: one GCM, major > one GCM, as major

2.4.1 Farm and farm management data:

•Line 264: Delete the colon (:). Do the same for the rest.

2.4.2 Soil data

•Line 283: form > from

•Table 2: What is soil type for Machanga? Please explain briefly the missing soil parameter in the discussion.

2.4.4 Model calibration and validation

•Line 318: CSMs s were > CSMs were

•Line 318-319: Please rephrase the sentence.

•Line 324: Table 4 > Table 4.

•Line 324: of 160 > from 160

•Line 328: are generally > are found to be generally

2.4.5 Crop simulations

•Line 353: left over > leftover

3.1 Trends in observed climatic conditions

•Line 403: expected have > expected to have

3.2 Projected 406 changes in climate conditions

•Line 413: compared to to other > compared to other

•Line 446: What is this sentence? "Impacts of climate change on maize productivity of the impact on maize." Is this a new sub-heading?

4.1 Climate Variability

•Line 631: log-term > long-term

4.3 Impacts of climate variability and change on maize production

•Line 714: and by when > and when

•Line 712-716: The sentences is too long. It can be separated into two sentences.

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7. PLOS authors have the option to publish the peer review history of their article (what does this mean?). If published, this will include your full peer review and any attached files.

If you choose “no”, your identity will remain anonymous but your review may still be made public.

Do you want your identity to be public for this peer review? For information about this choice, including consent withdrawal, please see our Privacy Policy.

Reviewer #1: Yes: Zulfaqar Sa'adi

[NOTE: If reviewer comments were submitted as an attachment file, they will be attached to this email and accessible via the submission site. Please log into your account, locate the manuscript record, and check for the action link "View Attachments". If this link does not appear, there are no attachment files.]

While revising your submission, please upload your figure files to the Preflight Analysis and Conversion Engine (PACE) digital diagnostic tool, https://pacev2.apexcovantage.com/. PACE helps ensure that figures meet PLOS requirements. To use PACE, you must first register as a user. Registration is free. Then, login and navigate to the UPLOAD tab, where you will find detailed instructions on how to use the tool. If you encounter any issues or have any questions when using PACE, please email PLOS at figures@plos.org. Please note that Supporting Information files do not need this step.

Attachments

Attachment

Submitted filename: Comments.docx

Simulating adaptation strategies to offset potential impacts of climate variability and change on maize yields in Embu County, Kenya

PONE-D-20-14901R3

Dear Dr. Gummadi,

We’re pleased to inform you that your manuscript has been judged scientifically suitable for publication and will be formally accepted for publication once it meets all outstanding technical requirements.

Within one week, you’ll receive an e-mail detailing the required amendments. When these have been addressed, you’ll receive a formal acceptance letter and your manuscript will be scheduled for publication.

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Kind regards,

Shamsuddin Shahid

Academic Editor

PLOS ONE

Additional Editor Comments (optional):

Reviewers' comments: