Observed Quasi 16-Day Wave by Meteor Radar over 9 Years at Mengcheng (33.4°N, 116.5°E) and Comparison with the Whole Atmosphere Community Climate Model Simulation

Round 1

Reviewer 1 Report

2.1: A photo of the meteo radar and/or station would benefit manuscript.

2.2: Use as title the full description of abbreviation, not the abbreviation.

Figs.9, 10: Top panel, check units of y axes

l.394-395: Correlation coefficients given in the text are wrong. Please check them.

Author Response

Response to the Comments and Suggestions

2.1: A photo of the meteor radar and/or station would benefit manuscript.

Response：Thanks for your suggestions. The photo of the meteor radar station has been added as Figure 1 in the revised manuscript.

2.2: Use as title the full description of abbreviation, not the abbreviation.

Response：Revised.

Figs.9, 10: Top panel, check units of y axes

Response：Thanks for the comments. It has been corrected.

l.394-395: Correlation coefficients given in the text are wrong. Please check them.

Response：Thanks for the comments. The coefficients in Figure 12 (Figure 11 in the elder version). As the coefficients in the text was not shown in the Figure 13, A description of the coefficients with respect to that presented in the figures are added in the revised manuscript as “The interannual variations in the solar cycle (F10.7) and instability (wind shear) seem unrelated to each other (the correlations between them are 0.22 in winter and -0.03 in summer, as shown in the upper panel of Figure 12)” In lines 396-398.

Author Response File: Author Response.docx

Reviewer 2 Report

This manuscript analyzed 9 years of the wind observations in the mesosphere and lower thermosphere at middle latitudes and investigated the quasi-16-day wave based on the observations. The upper layer atmospheric waves play an important role in the dynamics and the exchange and interaction between upper and lower layers. So the observations of the wave are very crucial. The topic of the paper is interesting and the 9 years long-term observations of the upper layer winds which could be an indicator of atmospheric wave is meaningful. The paper is well written and the logic is fluent. The observations and analysis are comprehensive. So I just accept. There is one comment I hope the author could consider to further improving the paper. The authors gave amount of results about the observations of the wind and wave but a little less discussion of the potential impacts and results of the observed waves on atmospheric dynamics, material exchange.

Author Response

Please see the attachment

Author Response File: Author Response.docx

Reviewer 3 Report

The subject of the manuscript is interesting and popular. The manuscript includes the results of observations of the quasi-16-day wave (Q16DW) by meteor radar over 9 years. A huge amount of Q16DW data has been analyzed based on measurements of zonal and meridional wind velocities. This represents a major contribution of the authors to the Q16DW studies. However, there is so much data that the manuscript is sometimes difficult to understand.

In total, I think that these data can be used to summarize information about the Q16DW. They do not contradict the data given in the References, but supplement them.

There are a few minor remarks.

Line 118: The authors do not explain the choice of the 61-day sliding window.

Figure 6: What is the meaning of Gaussian approximation? The same applies to Figure 8. Statistical hypothesis tests are used, but their criteria are not specified.

Figure 11: The top panel shows corr=0.5, while in the text on line 378 one can see a value of 0.45.

Line 393, 394: it is not clear what is the difference between the concepts of "correlation" and "correlation coefficient"? The authors use both terms.

The Reviewer hopes that the authors of the manuscript will take into account these minor comments and the manuscript will be accepted for publication.

Author Response

Please see the attachment

Author Response File: Author Response.docx

Reviewer 4 Report

The paper presents 9-years observations of 16-days planetary waves at a single location. The presented statistics may be useful for the scientists dealing with neutral wind in the MLT region. 

Minor corrections: 

19: There are two maxima in the Q16DW amplitude in the winter and early spring (near equinox), respectively, associated with the and a minimum during the summer.

34-35: The atmosphere between 60 km and 120 km, which is also referred to as the mesosphere and the lower thermosphere region (MLT), connects the lower atmosphere thermosphere and the upper atmosphere.

109: The reflected signals of the meteor tracks has have a Gaussian peak at approximately 90 km

Author Response

Please see the attachment

Author Response File: Author Response.docx

Reviewer 5 Report

This paper studied the quasi-16-day wave in the MLT during 2014-2022 by Mengcheng meteor radar. By using the up to nine years wind data, it is good way to observe the activities of Q16DW in the middle latitude. However, there are many aspects in this paper that need to be discussed carefully.

1. Fig 2: Why did the authors only choose 84 km to research Q16DW? They didn’t give the reason in the paper. What is the situation at other altitudes? Are the results similar to that at 84 km?

2. Lines160-162: From Fig.3, we could find the Q16DW is quite weak in the winter of 2020-2021, however is it because of major SSW? Since there are many SSWs during the nine years, it is obviously inappropriate for the authors to give this conjecture here.

3. About the statistical results: In the paper, the authors statistics the Q16DW periods, relative amplitude/phase differences and vertical wavelengths, however is it accurate to simply use every day to characterize the characteristics of Q16DW? Q16DW didn’t appear every day, and even if there are Q16DW, their periods and amplitudes vary greatly. I suggest the authors choose the determined Q16DW to statistics.

4. Phase difference: The results in Fig. 6 and Fig.7 are different, it is hard to conclude that the latitudinal and longitudinal fluctuations are orthogonal, especially in Fig.7, the phase difference varies greatly from 70-110 km.

5. Lines 271-278: The vertical wavelength formula is incorrect. The vertical wavelength doesn’t have relationship with period. Besides, the result of mean vertical wavelength is 200 km is also meaningless since the observed height is 40 km (70-100 km) and Q16DW would vary great in the 200 km height range. It is very hard to found a Q16DW to propagate 200 km or farther.

6. Discussion: Although the baroclinic instability is a wave source of PWs, the results in Fig.9 and Fig.11 couldn’t prove it. And the relationship between solar activities and waves is too weak to show in the paper.

I strongly recommend that the authors revise this paper carefully.

Author Response

Please see the attachment

Author Response File: Author Response.docx