Solar Extreme and Far Ultraviolet Radiation Modeling for Aeronomic Calculations

Round 1

Reviewer 1 Report

This paper gives a description of a newly built model of FUV and EUV. This is a potentially important contribution to the Aeronomy community. However, the paper is not well written. There are too many oral-written sentences and some of the figures are not well presented. The lines of the figures shall be in different colors so that the readers can clearly tell these different results. Furthermore, there is also errors in principle in the introduction. Therefore, I recommend this paper to have a major revision before it is suitable for publication.

 

 

Line 14 the sentence shall be separated into two. Put ‘.’ After ‘the Earth’s atmosphere’. Replace ‘the FUVT’ with ‘The FUVT’

 

Line 18 replace ‘simple’ with ‘simpler’

 

 

 

Line 25-26 This statement is not right. Actually, the thermosphere and ionosphere are always influenced by three major factors: solar radiation, geomagnetic activity, and lower atmosphere forcing (waves). There are no ‘most important’ terms. The author should rewrite the sentence as the following, and add necessary references.

 

The thermosphere and ionosphere are influenced by the joint efforts of solar radiation, geomagnetic activity and the lower atmosphere forcing. All these terms play important roles in the distribution of the thermosphere and ionosphere composition. Of the entire solar spectrum, far ultraviolet radiation from the Sun is the most significant for the formation of the upper atmosphere compositions.

 

For the reference after solar radiation, here are two examples:

 

Liu, L., W. Wan, Y. Chen, and H. Le (2011), Solar activity effects of the ionosphere: A brief review, Chin. Sci. Bull., 56, 1202–1211, doi:10.1007/s11434‐010‐4226‐9.

Liu, L., Wan, W., Ning, B., Pirog, O. M., and Kurkin, V. I. (2006), Solar activity variations of the ionospheric peak electron density, J. Geophys. Res., 111, A08304, doi:10.1029/2006JA011598.

For references after geomagnetic activity, here are two examples

 

Cai, X., Burns, A. G., Wang, W., Qian, L., Solomon, S. C., Eastes, R. W., et al. (2020). The two‐dimensional evolution of thermospheric ∑O/N₂ response to weak geomagnetic activity during solar‐minimum observed by GOLD. Geophysical Research Letters, 47, 2020GL088838. https://doi.org/10.1029/2020GL088838

 

Yue, X., W. Wang, J. Lei, A. Burns, Y. Zhang, W. Wan, L. Liu, L. Hu, B. Zhao, and W. S. Schreiner (2016), Long-lasting negative ionospheric storm effects in low and middle latitudes during the recovery phase of the 17 March 2013 geomagnetic storm, J. Geophys. Res. Space Physics, 121, 9234–9249, doi:10.1002/2016JA022984

 

For references after low atmosphere forcing, here are two examples

 

Goncharenko, L., J. L. Chau, P. Condor, A. Coster, and L. Benkevitch (2013), Ionospheric effects of sudden stratospheric warming during moderate-to-high solar activity: Case study of January 2013, Geophys. Res. Lett., 40, 4982–4986, doi:10.1002/grl.50980.

 

Liu, H.-L., V. A. Yudin, and R. G. Roble (2013), Day-to-day ionospheric variability due to lower atmosphere perturbations, Geophys. Res. Lett., 40, 665–670, doi:10.1002/grl.50125.

 

Line 27 I think it is better to write as ‘the composition of the upper atmosphere’

 

‘primarily ionization and dissociation of atmospheric gas molecules’

This is orally written, replace it with ‘which are mainly made up of ionization and dissociation of atmospheric gas molecules’

 

Line 31-33 the author shall provide the references to support the argument, especially the altitudes. I think the altitudes are changing, especially during storm time

 

Line 47 replace ‘, for example,’ with ‘such as ’

 

Line 72 replace ’; however, their use is difficult’ with ‘. However, it is difficult to use them’

 

Line 73-75 Please use a separate sentence, the old sentence is too long.

This is because it requires XXX

 

Line 76-77 again, orally written sentences. Revise them into

 

 

Line 122-123 I know the author only means developing EUV models here, but please clarify. Since there is also a large number of people developing first-principle model, which is mainly the solving groups of partial differential equations

 

Line 140 what is SEE?? Please give the full name

 

Line 159 again, orally written sentences. Revise them into

 

There is a question about which time series XXX

 

Figure 1  what is the grey line??

 

Line 184-187 this sentence is too long. Start the sentence in the ‘however’

 

Line 189-190 again, grammar error. Revise them into

When developing the model, the index N (LαC) was chosen, which will allow the reconstruction of the EUV and FUV spectra from 1947

 

Line 191 why there is a ‘,’ after ‘since’, there should not be

 

There are still many errors in grammar, I will not point out one by one

 

Figure 5 the date of year format is not consistent for two figures

 

Line 355-357 should be moved to before Line 350.

Line 370-371 the EUVT model can generate contradictory results, so is there any solutions? Or this statement may be harmful to the whole paper. And the conclusion did not mention this disadvantage, please clarify.

 

Line 372 again, grammar error revise into

the use of EUVT model can lead to contradictory results, which requires additional research.

Author Response

 Dear Referee,

Thanks a lot for Your careful reading of our paper and the comments made. We have taken them into account as much as possible and this helped us to improve the text. The paper has been revised. Additional analyses have been performed.  Please find our answers. 

 

 

This paper gives a description of a newly built model of FUV and EUV. This is a potentially important contribution to the Aeronomy community. However, the paper is not well written. There are too many oral-written sentences and some of the figures are not well presented. The lines of the figures shall be in different colors so that the readers can clearly tell these different results. Furthermore, there is also errors in principle in the introduction. Therefore, I recommend this paper to have a major revision before it is suitable for publication.

 

Of course, English is not our native language. Nevertheless we tried to make some corrections and improve the "oral-written sentences". Perhaps we did not succeed in this to the full, and we are ready to use the service offered by the edition, to correct language errors.
  We also converted some of the black and white figures to color when it was appropriate.

 

Line 14 the sentence shall be separated into two. Put ‘.’ After ‘the Earth’s atmosphere’. Replace ‘the FUVT’ with ‘The FUVT’           Done

 

Line 18 replace ‘simple’ with ‘simpler’    Done

 

  

Line 25-26 This statement is not right. Actually, the thermosphere and ionosphere are always influenced by three major factors: solar radiation, geomagnetic activity, and lower atmosphere forcing (waves). There are no ‘most important’ terms. The author should rewrite the sentence as the following, and add necessary references.

 

The thermosphere and ionosphere are influenced by the joint efforts of solar radiation, geomagnetic activity and the lower atmosphere forcing. All these terms play important roles in the distribution of the thermosphere and ionosphere composition. Of the entire solar spectrum, far ultraviolet radiation from the Sun is the most significant for the formation of the upper atmosphere compositions.

 

For the reference after solar radiation, here are two examples:

 

Liu, L., W. Wan, Y. Chen, and H. Le (2011), Solar activity effects of the ionosphere: A brief review, Chin. Sci. Bull., 56, 1202–1211, doi:10.1007/s11434‐010‐4226‐9.

Liu, L., Wan, W., Ning, B., Pirog, O. M., and Kurkin, V. I. (2006), Solar activity variations of the ionospheric peak electron density, J. Geophys. Res., 111, A08304, doi:10.1029/2006JA011598.

For references after geomagnetic activity, here are two examples

 

Cai, X., Burns, A. G., Wang, W., Qian, L., Solomon, S. C., Eastes, R. W., et al. (2020). The two‐dimensional evolution of thermospheric ∑O/N₂ response to weak geomagnetic activity during solar‐minimum observed by GOLD. Geophysical Research Letters, 47, 2020GL088838. https://doi.org/10.1029/2020GL088838

 

Yue, X., W. Wang, J. Lei, A. Burns, Y. Zhang, W. Wan, L. Liu, L. Hu, B. Zhao, and W. S. Schreiner (2016), Long-lasting negative ionospheric storm effects in low and middle latitudes during the recovery phase of the 17 March 2013 geomagnetic storm, J. Geophys. Res. Space Physics, 121, 9234–9249, doi:10.1002/2016JA022984

 

For references after low atmosphere forcing, here are two examples

 

Goncharenko, L., J. L. Chau, P. Condor, A. Coster, and L. Benkevitch (2013), Ionospheric effects of sudden stratospheric warming during moderate-to-high solar activity: Case study of January 2013, Geophys. Res. Lett., 40, 4982–4986, doi:10.1002/grl.50980.

 

Liu, H.-L., V. A. Yudin, and R. G. Roble (2013), Day-to-day ionospheric variability due to lower atmosphere perturbations, Geophys. Res. Lett., 40, 665–670, doi:10.1002/grl.50125.

 

 

Yes, variations in the ionosphere and upper atmosphere are also due to geomagnetic disturbances and processes in the lower atmosphere. But the ORIGIN of the ionosphere itself and the upper (at altitudes over ~ 120 km) atmosphere is primarily due to the ultraviolet radiation of the Sun. We believe that the presentation of well-known facts does not require additional explanations, especially supported by references. The purpose of this article is to describe a new tool for calculating the solar spectrum in the ultraviolet region. It is also beyond the scope of the article to compare the magnitudes of effects from disturbances of different nature. All this information can be found in any textbook, for example, in the monograph [2].

We gratefully accept your proposed phrase about factors affecting the thermosphere and ionosphere, it is included in the text of the introduction (lines 36-39). Nevertheless we believe that the inclusion of additional links will only lead to a useless increase in the volume of the article.

 

Line 27 I think it is better to write as ‘the composition of the upper atmosphere’
the word "composition"  was added in Line 25             done

 

‘primarily ionization and dissociation of atmospheric gas molecules’

This is orally written, replace it with ‘which are mainly made up of ionization and dissociation of atmospheric gas molecules’                 done

 

Line 31-33 the author shall provide the references to support the argument, especially the altitudes. I think the altitudes are changing, especially during storm time
Of course, the altitudes change during any perturbations. As we have said earlier, we do not consider any processes not concerning solar radiation. So we use sign "~" to show that these values are only rough

 

Line 47 replace ‘, for example,’ with ‘such as ’    done

 

Line 72 replace ’; however, their use is difficult’ with ‘. However, it is difficult to use them’          done

 

Line 73-75 Please use a separate sentence, the old sentence is too long.

This is because it requires XXX          done  

 

Line 76-77 again, orally written sentences. Revise them into

Corrected   done 

 

Line 122-123 I know the author only means developing EUV models here, but please clarify. Since there is also a large number of people developing, which is mainly the solving groups of partial differential equations

As we know, there are no first-principle models for radiation of the Sun as a star, since such models should include the position and emission measure of the of individual radiating structures on the Sun. There is one model for such structures:

Vernazza, J. E.; Avrett, E. H.; Loeser, R.  Structure of the solar chromosphere. III. Models of the EUV brightness components of the quiet sun. Astrophysical Journal, Suppl. Ser., 1981.Vol. 45, p. 635-725.  DOI: 10.1086/19073.

We add the words "Empirical-statistical" model to the text   Line 123    done

 

Line 140 what is SEE?? Please give the full name           done

 

Line 159 again, orally written sentences. Revise them into

 There is a question about which time series XXX  done

 

Figure 1  what is the grey line??

 The figure caption had been changed            done

 

 

Line 184-187 this sentence is too long. Start the sentence in the ‘however’   done

 

Line 189-190 again, grammar error. Revise them into

When developing the model, the index N (LαC) was chosen, which will allow the reconstruction of the EUV and FUV spectra from 1947             done

 

Line 191 why there is a ‘,’ after ‘since’, there should not be         done

 

There are still many errors in grammar, I will not point out one by one

 

Figure 5 the date of year format is not consistent for two figures
Corrected            done

 

Line 355-357 should be moved to before Line 350.

No, all is correct

 

Line 370-371 the EUVT model can generate contradictory results, so is there any solutions? Or this statement may be harmful to the whole paper. And the conclusion did not mention this disadvantage, please clarify.

 

Line 372 again, grammar error revise into

the use of EUVT model can lead to contradictory results, which requires additional research.

Clarification changes were inserted into Lines 370-372/

Reviewer 2 Report

This paper is competently written with a state of the art well presented.

However due to the high quality of the papers published in the Remote Sensing journal I kindly ask the authors to make the following improvements:

- please cite book chapters or review papers in the first part of the Introduction [lines: 25 - 33];

- line 60: the same FUV acronym is used for different expressions;

- line 131: perhaps VUSS-L?

- Due to the use of several acronyms, I recommend the authors to attach in a table all acronyms used here.

- line 160, 169, 234: Please correct with “alpha” for Lyman parameter; The same for eq: 1 and the x axis label from figure 2

- lines 272 – 273 and Figure 3: please add more discussions about why the authors prefers choosing the N(30.4C)

- equation 1, lines 282-283; 288-289; 336 – 345: I kindly ask the authors to include more discussions about choosing some values of the analysed parameters. It is quite confusing for some readers. Please cite where the case is. If the reader is not familiar with the model and associated issues, this paper isn't complete on its own.

Author Response

 Dear Referee,

Thanks a lot for Your careful reading of our paper and the comments made. We have taken them into account as much as possible and this helped us to improve the text. the paper has been revised. Additional analyses have been performed.  Please find our answers. 

 

 

please cite book chapters or review papers in the first part of the Introduction [lines: 25 - 33];

1.Okabe H. Photochemistry of small molecules, Wiley-Interscience, New York, 1978. 431 + vii pages. Chpt. 5, p.179

2. Ivanov-Kholodny, G.S.; Mikhailov, A.V. The Prediction of Ionospheric Conditions, D. Reidel Publishing Company Dordrecht, Holland. 1986. Chpt. 2, p.16

done

 

• line 60: the same FUV acronym is used for different expressions;

done

• line 131: perhaps VUSS-L?

—no, it was VUSS onboard CORONAS-F. VUSS-L works now onboard geostationary satellites Electro-L N 2 and Electro-L N 3

 

• Due to the use of several acronyms, I recommend the authors to attach in a table all acronyms used here.
  The result will be a table with information that has no scientific value. We believe the creation of such a table is unnecessary.
  done
• line 160,169, 234: Please correct with 'alpha" for Lyman parameter; The same for eq: 1 and the x axis label from figure 2 done

 

• lines 272 - 273 and Figure 3: please add more discussions about why the authors prefers choosing the N(30.4C)

It is quite simple: this line is one of the strongest in EUV region and it gives an essential input to ionization rate at F2 region altitudes.

  done

 

• equation 1, lines 282-283; 288-289; 336 - 345:1 kindly ask the authors to include more discussions about choosing some values of the analysed parameters. It is quite confusing for some readers. Please cite where the case is. If the reader is not familiar with the model and associated issues, this paper isn't complete on its own.

Total EUV flux determines total ionization rates at F1 and F2 altitude. We write it in lines 341-342.

 

 

Round 2

Reviewer 1 Report

The author has made corresponding revisions and the paper quality is greatly improved. I recommend it to be published in present form

Reviewer 2 Report

The revised manuscript is improved, and all comments and suggestions have been taken into consideration.