The Impacts of Climate Change, Carbon Dioxide Emissions (CO₂) and Renewable Energy Consumption on Agricultural Economic Growth in South Africa: ARDL Approach

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General

The presented models have been correctly selected, and the data have been properly transformed.

Well noted.

In subsequent studies, the author should consider a better selection of the research period. A longer period and more data do not always translate into correct conclusions. Figure 1 shows the logarithm of the input data over a period of 50 years. The variables lnCO2 and lnRENC are clearly divided into two periods in time. The approximate year of division is 1985.

The reviewer’s comment is noted and appreciated. Different research periods will be considered in future.

The analyzes were performed for all the data, which certainly increased the error in the model, which could have contributed to the fact that some of the hypotheses were not rejected. Test results in, for example, Table 8 may indicate this. In the literature review and methodology, the specificity of data collection up to and after 1985 (if there were any differences) should be provided.It is also worth mentioning what could have influenced such a clear change in the trends of these two variables. The discussion and conclusions should include information about the non-homogeneity of the period under review

A new section on the choice of data was added under the literature review to better explain the non-homogeneity within the data.

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General

I have thoroughly reviewed this manuscript and suggest the author revise the document by incorporating
the following comments.

Well noted.

The author is taking CO2, which is mainly responsible for global warming and is widely used as a proxy
for environmental degradation in literature along two weather components, i.e., temperature and
precipitation. Variation in meteorological indicators is basically triggered by GHG effect (carbon dioxide
is main contributor here).

The reviewer’s comments were noted. It is correct that CO2 and the two meteorological indicators measure environmental degradation. However, the three are not the same. CO2 measures pollution while the two meteorological indicators measure climate variability, an important indicator in the context of agriculture that cannot be replaced.

First, the author should be clear about the study's central hypothesis you
have not developed any theoretical framework for your study mere combination of some variable is
insufficient. Paper should be built on conceptual background. You need to discuss how selected (and
proposed variables in the following comments) variables fit into the scope of the study

The theoretical framework was added and the hypothesis was also added to improve the section.

The author
must revise model by dropping temperature and precipitation as we do not include atmospheric
pressure, wind, humidity, and cloudiness within the study. In this case, the author can add some control
variables like trade, urbanization, financial development, along with CO2 and renewable energy
consumption

The reviewers' comments are noted. However, various studies have used all the 3 variables (see table 2 added in the document). The meteorological indicators are of great importance in the paper especially because agriculture is highly associated with climate variability and the study would lose its strength if meteorological indicators are dropped and replaced with financial macroeconomic variables as suggested.   

The suggested variables are important and relevant however, removing the meteorological indicators and replacing them with these variables will change the entire study and focus and defeat the purpose of the paper. The variables will therefore be used in future studies.

Add

Further, the impact of the growth and other variables can be checked on emission by taking it as a
dependent variable (author can make it model 2). The study title should also be revised after the above comments incorporation

The comment is well noted.

Abstract

In the abstract, a specific solution and how the study is expected to provide any solution to a raised
problem should be given. General statements given in the last four lines of the abstract should be
avoided

Generalised solutions were amended as suggested in the abstract and the recommendation section as suggested.

Introduction

In the introduction, you claim that changes in climatic conditions will result in significant food
insecurity. But a lot of studies show that it has a catastrophic impact on food security. This and like
statements should be modified.

This statement is correct, and the reviewers' comment is also in agreement with the statement.

Avoid using chronic references as you are doing at the start of the
manuscript. The introduction failed to raise any specific novelty and hypothesis for the study. You are
jumping from one issue to another issue abruptly in the introduction. Revise it, and it should be
coherent and have a clear narrative

The hypothesis was added and novelty of the study was added and coherence was improved.

Methodology

I suggest using the latest modeling techniques, including structural breaks; for the unit root test, you
should apply the Zivote Andrews unit root test.

Overall your study is lying on first-generation and
outdated econometric methods.

Apply Bayer and Hanck Cointegration or Gregorye Hansen cointegration test

The reviewer’s comment is well noted. Literature shows that the Zivote Andrews test is necessary for the presence of structural breaks. The structural break was checked exogenously through the CUSUM test and structural breaks were not present therefore it was not necessary to conduct the  2^nd generation unit root test. This is informed by the previous work done by others.

The reviewers' comments are well noted. Although the suggestions of the latest econometric methods are welcomed. We disagree on the fact the methods employed in the study are outdated. There is enough evidence that the current technique used is and still is well accepted. Table 2 shows the latest similar studies that employed the same technique published in various journals.

Author is required to apply the Bootstrap ARDL approach, an advanced version of conventional ARDL,
for statistical analysis.

The comment is well noted and appreciated. The Bootstrap ARDL approach is an advanced version of the ARDL and the technique will be employed for future studies.

Conduct the analysis again including diagnostic and robustness tests for new proposed model(s) again
and re-write the results. Without incorporating these comments, I will suggest rejecting the
manuscript

The majority of the comments were incorporated. Unfortunately, the study variables were not changed due to the risk of re-directing the focus of the study.

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General

The Impacts of climate change, Carbon dioxide emissions (CO2) and renewable energy consumption on agricultural economic growth in South Africa: ARDL approach .The manuscript deals with an important topic of agricultural economic growth in South Africa. The results are potentially of global interest. 

While the authors presented about the ARDL approach, policy options and strategy, their influence on decision making are missing in the paper.

The paper could be useful to the authors for possible consideration if their information is clear and comprehensive in these aspects

Well noted.

The policy section was amended and the authors' voice was included as suggested.

The authors tried revising the paper to provide more clarity.

Abstract

Following suggestions are provided to improve the quality of the manuscript

1.The nexus was estimated using an Auto[1][1]regressive-Distributed Lag (ARDL) Bounds test econometric technique. 2. In the short run, findings indicated that climate change reduces agricultural economic growth and carbon dioxide emissions increase as agricultural economic growth increases. The use of renewable energy was insignificant in the short and long run. Carbon dioxide emissions granger causes temperature and renewable energy unilateral. An ARDL analysis was performed to evaluate the short and long-term relationship between agricultural economic growth, climate change, carbon dioxide emissions and renew able energy usage.

The suggestions are incorporated accordingly in the abstract.

Literature review

Following suggestions are provided to improve the quality of the manuscript:

1. The literature survey mainly relies on the several online resources. It will be better to enhance with scientific reports and literature on the issue of climate change, renewable energy and its effect on agriculture

Some information from reputable reports was added as suggested. E.g

IEA, G.E., 2019. CO2 Status Report 2018. International Energy Agency, Paris, 562.

United Nations Climate Change (2022)

Methodology

2. It would be appreciated if the author improved and updated the shortcoming of the analysis. 3 It is suggested to provide more comprehensive methodology section with clear steps involved

A section summarizing the methodology and table 1 with the steps taken under the methodology was added.

4. The quality of the data and the information can be improved. Similarly, Some Figures may be represented to show the results of the present analysis with respect to the topic discussed and impact on the policy on the global aspect as a whole?

The impact of the study on the policy was expanded under policy implications as suggested.

Literature review

6. Some specific insights on challenges on the agricultural economic market variation with climate change and renewable energy use as a whole are missing.

Challenges posed by market variations have been added under the literature review

Conclusion

7. Some of the conclusions drawn may be provided with key numbers and takeaways which may be useful for the policy support and readers to gain new knowledge on the topic

This was added under the policy implications.

5. The arguments presented in the analysis may provide some key questions which can be lately addressed by the other researchers 

A section for future research was added.

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Response

General

The authors appropriately examined and evaluated the topic. only some minor suggestion can be added to the manuscript:

Well noted.

Method

1. what is the pros and cos of the ARDL approach for the study. 

Done: The strengths and weaknesses of the ARDL were included and discussed.

Chart/Results

2. A chart can be good prsentation to show the relation between obtainings, results, needs and suggestions. 

A graphical abstract was added under Annexure A as suggested