Simulating Potential Impacts of Future Climate Change on Post-Rainy Season Sorghum Yields in India
, Sridhar Gummadi 3,*, Koteswara Rao Kundeti 4, Dakshina Murthy Kadiyala 5, Kumara Charyulu Deevi 2, Kailas Kamaji Dakhore 6, Ranjitha Kumari Bollipo Diana 1 and Senthil Kumar Thiruppathi 1Round 1
Reviewer 1 Report
The paragraph 2 in methodology section is a a repeated section from Introduction.No need to include growing conditions and the uses of Sorghum again in methodology.
The paper has included several experiments, i.e. rainfall and temperature variation in growing districts, yield predictions for historical and future scenarios. However, the DSSAT model calibration procedure and how coefficients are derived is not clearly explained.
Author Response
We truly appreciate the thorough review and comments offered on our article. These critical comments helped us a lot in bringing more clarity to our manuscript. After careful consideration of the general and specific comments suggested, we have drafted our responses below (in Bold) and made appropriate changes in the attached revised article in track change mode.
The paragraph 2 in methodology section is a repeated section from Introduction. No need to include growing conditions and the uses of Sorghum again in methodology.
- As suggested by the reviewers the repeated text was removed from materials and methods and this section was trimmed to improve the readability
The paper has included several experiments, i.e. rainfall and temperature variation in growing districts, yield predictions for historical and future scenarios. However, the DSSAT model calibration procedure and how coefficients are derived is not clearly explained.
- The cultivar used in this study was earlier calibrated and evaluated by (Singh et al., 2014 and Sandeep et al., 2018) based on long-term All India Coordinated Research Project on Sorghum (AICRPS) trials. For this study, we have used the validated and calibrated crop coefficients that were previously published by (Singh et al., 2014 and Sandeep etal., 2018).
Author Response File: 
Author Response.docx
Reviewer 2 Report
To improve the manuscript some comments are proposed:
- The first part of the introduction section (L 42-109) about the importance of sorghum crop India can be simplified to better organize this section.
- Why authors did not use the data of Hengl et al (2017) or Poggio et al (2021) which offer a 250 m resolution of soil properties prediction
- According to the sensitivity of crop model to soil properties, it is necessary to perform a validation of soil properties (coming from global map Hengl et al 2014, Hengl et al, 2017, …) using some observed date in India.
- Som clarifications are needed about downscaling of soil prperties data for modelling
Line 30 : - 4% is a decrease
Line 50 : reference
Line 73 : reference for national data
Line 104 : reference
Line 109 : reference
Line 113 : some references are needed
L 110-116 : are there some studies related to the effect of climate change on sorghum production in India ?
Line 123 : delete “gigantic”
Line 203-204: how authors upscaled soil data to run model at 0.25x0.25, clarification must be added
Comments for author File: 
Comments.pdf
Author Response
We truly appreciate the thorough review and comments offered on our article. These critical comments helped us a lot in bringing more clarity to our manuscript. After careful consideration of the general and specific comments suggested, we have drafted our responses below (in Bold) and made appropriate changes in the attached revised article in track change mode.
To improve the manuscript some comments are proposed:
The first part of the introduction section (L 42-109) about the importance of sorghum crop India can be simplified to better organize this section.
We appreciate the reviewer comments and as per the advice we totally revised the introduction part updated in the revised manuscript.
Why authors did not use the data of Hengl et al (2017) or Poggio et al (2021) which offer a 250 m resolution of soil properties prediction
We agree with the authors that using 250 m soil data may fine-tune the simulation yields, however as management practices and weather data are not available at that fine-scale and also it is difficult to compare observed yields with predicted as observed yield data is available only at the district level. Hence as stated in the materials and methods we selected the soil profile that has the maximum area under the rainfall grid (25 x 25 km grid).
According to the sensitivity of crop model to soil properties, it is necessary to perform a validation of soil properties (coming from global map Hengl et al 2014, Hengl et al, 2017, …) using some observed date in India.
We validated the simulated yields obtained from this study with long-term district-level data and we found that the model could able to represent the actual yields at a reasonably acceptable level. However, it will be interesting to study the sensitivity of the model to soil properties but due to lack of a location-specific long-term yield database at field level may be a limiting factor.
Some clarifications are needed about downscaling of soil properties data for modeling
For the current study, we have used 1 km spatial resolution soil data, however, due to the non-availability of climate and other crop management data at 1 x 1 km resolution, we have spatially selected the soil profile that has the maximum area under the rainfall grid (25 x 25 km) and then forced the crop model.
Line 30 : - 4% is a decrease
As suggested, we have replaced the "increase" with "varying between"
Line 50 : reference
Provided reference as advised
Line 73 : reference for national data
Provided reference
Line 104 : reference
Provided reference
Line 109 : reference
Provided reference
Line 113 : some references are needed
Provided reference
L 110-116 : are there some studies related to the effect of climate change on sorghum production in India ?
There are studies on the impacts of climate change on sorghum crops but not specific to the post-rainy season (Srivastava et al., 2010) which is more focused on Kharif season and the simulations were limited to a couple of GCMs. The current study is focused on using the multi climate model projections to assess the possible potential impacts of climate change on post-rainy season sorghum crops.
Line 123 : delete “gigantic”
Deleted “gigantic” as suggested
Line 203-204: how authors upscaled soil data to run model at 0.25x0.25, clarification must be added
We agree with the reviewer's comment on this and we modified the text to get clarity on this. in the study we initially started simulating 1km grids for sorghum but to simulate all sorghum growing regions we end up with millions of simulations. Further, we also tried with 1km grid simulations and we didn’t find many variations in crop model yields as weather and management practices are constant for the entire 0.25 x 0.25o grid, hence we restricted our simulations to 0.25 x 0.25.
“In this current study, we used soil data from SoilGrids1km developed by ISRIC, however as the rainfall data is available for only at 0.25x0.25o we restricted the crop model simulations to 0.25x0.25o only as simulating at 1 km soil grids is computationally very expensive.
Author Response File: Author Response.docx
Reviewer 3 Report
I went through the manuscript entitled: Simulating potential impacts of future climate change on post-rainy season sorghum yields in India, and found it interesting. The authors evaluated potential impacts of climate change in the future on sorghum in India emphasis on post-rainy season. They used some models and got some important results.
Introduction is too long for this manuscript, as the general contents about sorghum is greater than what needed. Details in materials and methods are good enough to repeat this research by someone. Some abbreviations are not defined at the first time. Or some abbreviations in figures were not defined in the captions. Figure 5 refers to which area? Please mention in the caption. Conclusion should be shortened.Author Response
We truly appreciate the thorough review and comments offered on our article. These critical comments helped us a lot in bringing more clarity to our manuscript. After careful consideration of the general and specific comments suggested, we have drafted our responses below (in Bold) and made appropriate changes in the attached revised article in track change mode.
I went through the manuscript entitled: Simulating potential impacts of future climate change on post-rainy season sorghum yields in India, and found it interesting. The authors evaluated potential impacts of climate change in the future on sorghum in India emphasis on post-rainy season. They used some models and got some important results.
Introduction is too long for this manuscript, as the general contents about sorghum is greater than what needed. Details in materials and methods are good enough to repeat this research by someone. Some abbreviations are not defined at the first time. Or some abbreviations in figures were not defined in the captions. Figure 5 refers to which area? Please mention in the caption. Conclusion should be shortened.
The introduction was trimmed to improve the readability. As commented by the reviewers the abbreviations and acronyms were defined and updated in the revised manuscript. Updated figure 5 caption and provided the study area. As advised the conclusion sections are shortened.
Author Response File: Author Response.docx
