Diurnal Variations of Different Cloud Types and the Relationship between the Diurnal Variations of Clouds and Precipitation in Central and East China
Round 1
Reviewer 1 Report
This study is a comprehensive analysis between the cloud types and precipitation across China. It is thorough in that it covers multiple cloud types and the entire geographical extent.
One of the main concerns is that the authors discuss correlation coefficients in Section 4.2 but do not show any of this work in the methodology nor results section. It may be a good idea to place some of this in a supplementary information section.
There are some grammar and general English writing concerns and it would be useful to have a native speaker edit and fix these issues.
The future work section (last part of the manuscript) is very unclear and could use significant improvement, detail, and expansion if the authors do intend on pursuing the additional work.
Specific concerns:
Equations 2 and 4 are poorly written because the first clause (T1 > 0) will hold even if the third clause (T1 > 24) holds. Please re-write more clearly
Line 290 is an unclear sentence that is also grammatically incorrect.
Line 294 has a grammar and punctuation error.
The authors should not use "obvious" - use "clear" instead.
Author Response
Dear editors and reviewers,
Thank you very much for your evaluation and for your insightful commentary. Your comments and suggestions greatly helped us to improve our manuscript. In the following response, the black text denotes the comments from the editors and reviewers, while the blue text represents our responses. We look forward to hearing from you soon.
1. One of the main concerns is that the authors discuss correlation coefficients in Section 4.2 but do not show any of this work in the methodology nor results section. It may be a good idea to place some of this in a supplementary information section.
Response: Thank you for your suggestion. We have place the information of correlation coefficients in the conclusion section in our revised manuscript.
2. There are some grammar and general English writing concerns and it would be useful to have a native speaker edit and fix these issues.
Response: We have improved our English in the revised manuscript.
3. The future work section (last part of the manuscript) is very unclear and could use significant improvement, detail, and expansion if the authors do intend on pursuing the additional work.
Response: Thank you for your suggestion. In the future work section, we briefly show the main content of our next work.
4. Equations 2 and 4 are poorly written because the first clause (T1 > 0) will hold even if the third clause (T1>24) holds. Please re-write more clearly.
Response: We apologize, equation 2 and 4 are not rigorous. The first clause (T1>0) of equation 2 has been modified to (0<T1<=24). Since the method used to convert GMT into LST is similar, we described the method to convert GMT to LST in one sentence, and delete equation 3 and 4 in the revised manuscript.
5. Line 290 is an unclear sentence that is also grammatically incorrect.
Response: We apologize, the original sentence was unclear. The sentence has been changed to “While Ns shows clear zonal difference over the Yangtze River valley and its south side, where the occurrence frequency of Ns is the largest”.
6. Line 294 has a grammar and punctuation error.
Response: The sentence have been modified, please see lines 297-298.
7. The authors should not use “obvious” – use “clear” instead.
Response: In our revised version “obvious” have been replaced by “clear”.
Reviewer 2 Report
Review of "Diurnal Variations of Various Clouds and the 2 Relationship Between the Diurnal Variations of 3 Clouds and Precipitation in Central and East China" by Gao et al., 2019.
The manuscript fits within journal scope as investigates cloud an precipitation diurnal variability over 25 years of observations across 114 ground-based met stations. Nevertheless, in some parts the paper is not clear and should be improved before publication.
Major comments:
The occurrence of mid and high cloud might be underrepresented, as ground observations are not able to detect multiple cloud systems, especially during convective hours. The authors make no reference to this issue. Ci peaks about 23%, while this frequency is higher as stated in https://journals.ametsoc.org/doi/full/10.1175/JAMC-D-16-0262.1 and https://www.sciencedirect.com/science/article/pii/S1352231011008375. The authors should refer this issue and also maybe describe how frequent are multiple cloud systems as stated in https://www.sciencedirect.com/science/article/pii/S0022407310003924 .
Even if a climatological over more than 25 years is interesting, it worth investigating for the different cloud types how much the frequency occurrence changed with respect to the years. Those results might be very interesting for the feedback exerted by the clouds on climate.
The specific comments are reported in the attached file.
Comments for author File: 
Comments.pdf
Author Response
Dear editors and reviewers,
Thank you very much for your evaluation and for your insightful commentary. Your comments and suggestions greatly helped us to improve our manuscript. In the following response, the black text denotes the comments from the editors and reviewers, while the red text represents our responses. We look forward to hearing from you soon.
1. The occurrence of mid and high cloud might be underrepresented, as ground observations are not able to detect multiple cloud systems, especially during convective hours. The authors make no reference to this issue. Ci peaks about 23%, while this frequency is higher as stated in https://journals.ametsoc.org/doi/full/10.1175/JAMC-D-16-0262.1 and https://www.sciencedirect.com/science/article/pii/S1352231011008375.The authors should refer this issue and also maybe describe how frequent are multiple cloud systems as stated in https://www.sciencedirect.com/science/article/pii/S0022407310003924.
Response: From the perspective of surface observations, the diurnal variation of low clouds are relatively accurate. High clouds and middle clouds are sometimes blocked by low clouds, there are two methods to analyze the diurnal variation of clouds. One is to analyze the diurnal variation of a certain type of high (middle) cloud when it appears, the other is to compare the diurnal variation of high clouds observed by satellite with that observed by surface observations, and we used the former method. While Liu, et al. analyzed the diurnal variation of total clouds, high clouds and low clouds based on ISCCP (International Satellite Cloud Climatology Project) data, the results showed that the diurnal variation of high clouds analyzed with ISCCP are consistent with those analyzed with the surface data. Therefore, we believe that the shading can only produce errors in the magnitude and does not affect the analysis of diurnal variation.
Liu, Q. and Fu, Y. F. (2009). The climatological feature of diurnal variation of cloud amount over the topics. Journal of Tropical Meteorology, 25(6): 717-724.
2. Even if a climatological over more than 25 years is interesting, it worth investigating for the different cloud types how much the frequency occurrence changed with respect to the years. Those results might be very interesting for the feedback exerted by the clouds on climate.
Response: In our previous work (Gao et al. 2015), we have investigated the occurrence frequency of different cloud types change with the years.
Gao, C. C., Fang, L. X., Li Y. Y, et al. (2015). Cloud occurrence frequency, duration time and accompanying rainfall probability in China during 1985-2011. Torrential Rain and Disaster, 34(3): 206-214.
3.”various clouds” to “different cloud types”
Response: Done.
4.”diurnal variations”
Response: The meaning of these two words is not repeated, and many seniors use them like this.
Yu, R. C., Zhou, T. J., Xiong, A. Y. et al. (2007a). Diurnal variations of summer precipitation over contiguous China. Geophysical Research Letters. 34: L01704.
Chen, H. M., Yu, R. C., Wu, B. Y. (2012). FY-2C derived diurnal features of clouds in the southern contiguous China. J Geophys Res, 117(D18):D18101.
Brian J. Soden (2000). The diurnal cycle of convection, clouds, and water vapor in the tropical upper troposphere. Geophysical Research Letters. 27(15): 2173-2176.
5. “Various meteorological parameters in the surface layer, such as the temperature field, wind field, pressure field and precipitation, all show significant diurnal variations.” to “Various meteorological parameters, such as the temperature, wind, pressure and precipitation, all show significant diurnal variations.”
Response: Done.
6. “The formation mechanism of precipitation is complex; however, it originates from clouds, and it is the product of cloud development.” the sentence is pretty trival.
Response: The sentence has been changed to “The formation mechanism of precipitation is complex, but it is ultimately originated from clouds”.
7. Some most recent research should be added.
Response: We have added some recent research in the revised manuscript.
8. “Quality-control procedure is performed” please briefly explain in which the quality control consists.
Response: First, the stations with observing frequency less than 80% were eliminated. Second, stations with a bad data rate of more than 10% were also eliminated. Finally, there were 114 stations of cloud data met the requirements.
9. It is not explained what (a), (b), (c) mean in figure1.
Response: We have added the explaination of (a), (b), (c) in figure1 in our revised manuscript.
10. Ci is also related to warm fronts.
Response: Here we want to express the relationship between Ci and other clouds, rather than the relationship between Ci and weather systems.
11. The diurnal variations of precipitation among the different regions are dominated by different clouds.
Response: The sentence has been changed to “The diurnal variations of precipitation among the different regions are dominated by convective or stratiform clouds.”
Reviewer 3 Report
Gao et al. “Diurnal Variations of Various Clouds and the Relationship Between the Diurnal Variations of Clouds and Precipitation in Central and East China”
This study provides useful and valuable statistical analysis results about the variations of clouds and precipitation. As the authors indicated, precipitation must be associated with clouds, what is the scientific question or goal for investigating the relationship of diurnal variation between clouds and precipitation? This is the major concern I have. In principle, this is a nice study I would like to recommend for publication after a minor revision.
Detailed comments:
Line 12-14, Since you have data from 1985 to 2011, why do you only focus on the relationship between the diurnal variations of clouds and precipitation in the summers from 2008 to 2011?
Line 51 “beneficial”
Line 68 “aforementioned”
Line 74-95, Zhao et al. (2018, DOI:10.1002/joc.5975) showed the statistical characteristics of cloud properties, along with the difference between morning (10:30 AM) and afternoon (1:30 PM) based on MODIS observations, which should be cited also here. Moreover, the cloud property statistical analysis by Bao et al. (2018, Doi: 10.1109/JSTARS.2018.2857827) could also be referred.
Line 99, how did you make the quality control?
Line 104-107, a little information about the uncertainty could be helpful.
Line 138-144, I do not think it is necessary to show how you make the time zone change, which is common knowledge. This is a scientific paper, and one sentence to mention is enough.
Line 226, “represents”
Author Response
Dear editors and reviewers,
Thank you very much for your evaluation and for your insightful commentary. Your comments and suggestions greatly helped us to improve our manuscript. In the following response, the black text denotes the comments from the editors and reviewers, while the blue text represents our responses. We look forward to hearing from you soon.
1. This study provides useful and valuable statistical analysis results about the variations of clouds and precipitation. As the authors indicated, precipitation must be associated with clouds, what is the scientific question or goal for investigating the relationship of diurnal variation between clouds and precipitation? This is the major concern I have. In principle, this is a nice study I would like to recommend for publication after a minor revision.
Response: The nature of precipitation originated from different types of clouds is different, including convective and stratiform precipitation. Investigating the relationship of diurnal variation between clouds and precipitation is helpful for understanding the nature of precipitation in different regions, and it is beneficial to improve the ability to simulate convective and stratiform precipitation in weather and climate models.
2. Line 12-14, Since you have data from 1985 to 2011, why do you only focus on the relationship between the diurnal variations of clouds and precipitation in the summers from 2008 to 2011?
Response: Since the starting date of the hourly merged precipitation data is January 1, 2008, and precipitation in central and east China mainly occurs in summer, so we focus on the relationship between the diurnal variations of clouds and precipitation in the summers from 2008 to 2011.
3. Line 51 “beneficial”, Line 68 “aforementioned”, Line 226, “represents”
Response: We have checked and improved our English in the revised manuscript.
4. Line 74-95, Zhao et al. (2018, DOI:10.1002/joc.5975) showed the statistical characteristics of cloud properties, along with the difference between morning (10:30 AM) and afternoon (1:30 PM) based on MODIS observations, which should be cited also here. Moreover, the cloud property statistical analysis by Bao et al. (2018, Doi: 10.1109/JSTARS.2018.2857827) could also be referred.
Response: We have added the recent research about characteristics of cloud properties in line 75-99 in our revised manuscript. And we have added the recent research about the effect of the cloud radiative forcing in line 46.
5. Line 99, how did you make the quality control?
Response: First, the stations with observing frequency less than 80% were eliminated. Second, stations with a bad data rate of more than 10% were also eliminated. Finally, there were 114 stations of cloud data met the requirements.
6. Line 104-107, a little information about the uncertainty could be helpful.
Response: We have added the advantage and uncertainty of surface observations in the revised manuscript, please see lines 111-114.
In addition, From the perspective of surface observations, the diurnal variation of low clouds are relatively accurate. High clouds and middle clouds are sometimes blocked by low clouds, there are two methods to analyze the diurnal variation of clouds. One is to analyze the diurnal variation of a certain type of high (middle) cloud when it appears, the other is to compare the diurnal variation of high clouds observed by satellite with that observed by surface observations, and we used the former method. While Liu, et al. analyzed the diurnal variation of total clouds, high clouds and low clouds based on ISCCP (International Satellite Cloud Climatology Project) data, the results showed that the diurnal variation of high clouds analyzed with ISCCP are consistent with those analyzed with the surface data. Therefore, we believe that the shading can only produce errors in the magnitude and does not affect the analysis of diurnal variation.
Liu, Q. and Fu, Y. F. (2009). The climatological feature of diurnal variation of cloud amount over the topics. Journal of Tropical Meteorology, 25(6): 717-724.
7. Line 138-144, I do not think it is necessary to show how you make the time zone change, which is common knowledge. This is a scientific paper, and one sentence to mention is enough.
Response: Thank you for your suggestion. We have modified it, and described the method to convert GMT to LST in one sentence.
Round 2
Reviewer 2 Report
The manuscript really improved since the previous version and now it is ready for publication. I would suggest the authors to carefully check the resolution of all the figures and labels and titles size.
Author Response
Dear editors and reviewers,
We have checked the lables and titles of all the figures. And we have redrawn figure 6 in the revised manuscipt. We're looking forward to hearing from you.
