Comparing the Trajectory of Urban Impervious Surface in Two Cities: The Case of Accra and Kumasi, Ghana
Round 1
Reviewer 1 Report
The authors have done detailed work on ‘Comparing the Trajectory of Urban Impervious Surface in Two 2 Urban Cities: The Case of Accra and Kumasi, Ghana.’ Some improved work can be added to the manuscript.
1. The typical descriptions of Accra and Kuma as two studied cities in Ghana are insufficient and need to be described in detail.
2. Please add different colors to Figure 4.
3. More descriptions should be added to the innovation of the article.
Author Response
Dear Reviewer,
Thank you for taking time out of your busy schedule to review our article; we found your comments very insightful. Find below your comments and our response. Apart from your comments, we have also made other changes to our article, which we highlighted in red (See attached the revised article).
- The typical descriptions of Accra and Kuma as two studied cities in Ghana are insufficient and need to be described in detail.
Response: We have updated the description of the study sites (see lines89-106).
- Please add different colors to Figure 4.
Response: We have replaced figure 4 and 5 with a single figure called Figure 4. The new figure has updated colors.
- More descriptions should be added to the innovation of the article.
Response: Thank you for your suggestion. We reviewed our article and believe that the article has sufficient innovation to address the objective of our research. We, therefore, draw your attention to lines 42-51, which outline the innovation of our data creation techniques. Furthermore, lines 52-80 outline some of the popular methods for measuring change and their associated limitations, while lines 81-86 outline how our methodology solves the limitations.
Author Response File: 
Author Response.pdf
Reviewer 2 Report
The selected research topic is quite interesting. However, some points must be addressed to enhance the study's quality.
1. Section 2.2: Separate explanations of data and methodology are essential.
2. LN 102-103: It seems that many satellite images are used to compile the data for each year. For example, for 2000, twenty-four images appear to have been used. Could you please let me know the method that you have used to compile this image to produce one single image for each? Have you sue mean or median?
Author Response
Dear Reviewer,
Thank you for taking time out of your busy schedule to review our article; we found your comments very insightful. Find below your comments and our response. Apart from your comments, we have also made other changes to our article, which we highlighted in red (See attached the revised article).
- Section 2.2: Separate explanations of data and methodology are essential.
Response: We have updated our article to reflect your recommendation. See lines 107 and 136.
- LN 102-103: It seems that many satellite images are used to compile the data for each year. For example, for 2000, twenty-four images appear to have been used. Could you please let me know the method that you have used to compile this image to produce one single image for each? Have you sue mean or median?
Response: We applied a median reducer to generate a single image for each year. We have added this information to section 2.2. (See red text at line 112).
Author Response File: Author Response.pdf
Reviewer 3 Report
This manuscript introduces new methods to assess newly developed urban impervious surfaces (UIS) datasets derived from satellite imagery for Kumasi and Accra, Ghana at three time points. In the study, each city has three bi-nary maps from 2000, 2011, and 2021 where 1 shows the presence of UIS and 0 shows absence. The study employed the binary Time Series method to compare the gross gains and losses in the two cities. The study also show how three components of change: Quantity, Allocation, and Alternation compare across the two sites. The results demonstrate that both cities experienced a large proportion of gains in the change of impervious surface during 2000-2011 and 2011-2021 with relatively smaller loss proportions and Alternation. Comparatively, the results from the components of change show that change is fastest in Kumasi, which had a larger proportion of Quantity Gain. The used methods show an acceleration of UIS in the two cities during the temporal extent, and this trend is likely to continue with increasing urban populations. Therefore, Land Use and Spatial Planning Authority, Town and Country Planning and stakeholders make contingency plans to regulate unplanned increase in UIS since other studies have shown the negative effects on people and the environment.
However, there are a few places to be improved as below:
1) Line 39, [4][5][6] should be [4-6];
2) Line 76, [19][20][21][22] should be [19-22];
3) In Figure 5, the legend is required;
4) data validation should be mentioned in Results;
5) references should be updated.
Author Response
Dear Reviewer,
Thank you for taking time out of your busy schedule to review our article; we found your comments very insightful. Find below your comments and our response. Apart from your comments, we have also made other changes to our article, which we highlighted in red (See attached the revised article).
1) Line 39, [4][5][6] should be [4-6];
Response: we have updated the citations.
2) Line 76, [19][20][21][22] should be [19-22];
Response: We have updated the citations.
3) In Figure 5, the legend is required;
Response: We have replaced figure 4 and 5 with a single figure called Figure 4. The new figure has an appropriate legend.
4) data validation should be mentioned in Results;
Response: We have included information about data validation under Results (See section 3, lines 185-190)
5) references should be updated.
Response: We have updated all reference.
Author Response File: Author Response.pdf
Round 2
Reviewer 1 Report
The author has responded well to my comments
Reviewer 2 Report
The comments have been addressed
Reviewer 3 Report
After its revision, it is agreed to be accepted for publication.
