A Study on the Effectiveness of SCD Seeding Fog Dissipation Mechanism Using LiDAR Sensor

Round 1

Reviewer 1 Report

The authors must give more explanations in the paper why the distance is the same for the concentration of seeding particles 500 and 1000g for some time intervals ( e.g., at 1100seconds, see Fig.4).

Please, use filled triangles in Figs. 4 and 8.

Comments for author File: Comments.pdf

English can be improved.

Author Response

Dear reviewer 1,

Please check the attached reply.

thank you

Author Response File: Author Response.docx

Reviewer 2 Report

Article of “A Study on the Effectiveness of SCD Seeding Fog Dissipation 2 Mechanism Using LiDAR Sensor” by Wang et al.

 

In this study, two methods of natural dissipation by gravity sedimentation and solid carbon dioxide seeding fog dissipation mechanism were compared and analyzed in cold fog conditions. The light detection and ranging (LiDAR) sensor and a camera were used to observe the fog dissipation phenomenon. This study is interesting. But some statements in the manuscript did not catch the information in the figures and tables. Some figures are hard to understand, even without words explaining them. Therefore, I suggest a major revision before publishing.

 

Major Comments

 

 

1. Introduction section. The authors should provide a short summary of the mechanisms of fog forming and dissipating in nature, also including the changes of fog microphysics characteristics in different fog stages. The following reference could be helpful.

Gultepe et al., 2007, https://doi.org/10.1007/s00024-007-0211-x

Niu et al., 2012, https://doi.org/10.1007/s00024-011-0344-9

Wang et al., 2021, https://doi.org/10.1007/s11430-020-9766-4

 

2. In sections 3.1 and 3.2, the authors conducted fog dissipation tests using the subcooling mechanism of SCD at a room temperature of -1 °C and a humidity of 50-55%. How about other different conditions? I suggest the authors furtherly conduct several groups of controlled experiments to explore the effect of SCD seeding on fog dissipation under different temperature and humidity conditions.

 

3. In section 4.3, the author states that “The experimental results of this paper were compared and analyzed with the results of Kampe et al. [5], which seeding SCD to actual clouds using airplanes (refer to Fig. 7). In the reference paper [5], the experiment was conducted by seeding SCD at about 304 m (1,000 ft) above the sky.” However, the authors plotted the fog dissipation conditions at three different heights in Figure 7. I would like to ask whether the figure means seeding SCD at three heights and observing the fog dissipation later, or seeding SCD at 1000ft and observing the visible conditions at three heights from the ground? I don't know what the figure is trying to express from your statement. Figure 8 and Table 4 use the result of Kampe., et al at 800ft, 1000ft and 1200ft, but the three heights in Figure 7 are obviously not 800ft, 1000ft and 1200ft. It is difficult for me to understand the comparison results in this section. Please re-describe the information in the figures and tables. The captions of the figures and tables do not even have legend information and needs to be rewritten.

 

4. There is no explanation for the results of Figure 8 and Table 4 in the article, only one sentence “As can be seen in Fig. 8, the results of this study and the referenced study [5] were compared.” Please supplement. Moreover, Figure 8 and Table 4 compare the results of this study and Kampe's study in 1957. What is the relationship between the previous study on observing fog dissipating at different heights and your observation of fog dissipating with different seeding amounts? What is the significance of the comparison? Please further state. If you can only obtain conclusions such as " SCD has an effect on dissipating fog (cloud) particles." in Conclusion 4. Such the conclusion is well known and does not need to be written.

 

5. Conclusion 1 states that “Due to the space limitations of the lab-scale chamber, it was determined that energy conversion had a limit. Therefore, further studies are required to optimize the amount of SCD suitable for the space size.” However, the results in the manuscript show that visibility improved with increased SCD seeding. The limit was not stated.

 

Minor Comments

L29. “The fog that occurs most in inland South Korea is radiation fog.” Reference needs to be supplied to support your conclusion.

 

L176. Figure 3 and the caption of the figure should be on the same page.

 

L251. The authors may need to reconsider how the caption of the figure be expressed.

 

L277. The unit conversion error in Figure 8. The legend should be 800ft (244m), 1000ft (305m), 1200 (366m).

 

L280-284. The T in the caption of Table 4 is not defined. The row numbers for 281, 282, 283, and 284 are embedded in the table and need to be modified.

 

L278, L280. The captions of Figure 8 and Table 4 are too simple. You should describe all the variables and their units in the captions.

 

L291-300. I suggest combining conclusion 2 and conclusion 3 into one.

 

The published year of Ref.4 “Supercooled Fog Dispersal for Airport Operations” is 1965 rather than 2011.

 

Moderate editing of English language

Author Response

Dear reviewer 2,

Please check the attached reply.

thank you

Author Response File: Author Response.docx

Round 2

Reviewer 1 Report

I suggest to publish this paper as it stands.

Reviewer 2 Report

The authors have addressed all my questions. I recommand it for publishing.