Synergistic effects of previous winter NAO and ENSO on the spring dust activities in North China

Xu, Falei; Wang, Shuang; Li, Yan; Feng, Juan

doi:https://doi.org/10.5194/egusphere-2024-955

Preprints

https://doi.org/10.5194/egusphere-2024-955

Preprints

09 Apr 2024

| 09 Apr 2024

Synergistic effects of previous winter NAO and ENSO on the spring dust activities in North China

Falei Xu, Shuang Wang, Yan Li, and Juan Feng

Abstract. Dust plays an important role in influencing global weather and climate via impacting the Earth's radiative balance. Based on the atmospheric and oceanic datasets during 1980–2022, the impacts of preceding winter North Atlantic Oscillation (NAO) and El Niño-Southern Oscillation (ENSO) on the following spring dust activities over North China are explored. It is found that both NAO and ENSO exert significant effects in influencing the dust activities over North China, particularly during their negative phases. A synergistic influence on the dust activities in North China is observed when both NAO and ENSO are in negative phase, with their combined impacts exceeding that of either factor alone. The previous winter NAO exhibits significant impacts on the sea surface temperatures (SST) in the North Atlantic, associating with an anomalous SST tripole pattern. Owing to the persistence of SST, these anomalies can extend into the following spring, when anomalous atmospheric teleconnection wave trains would be induced, thereby influencing the dust activities in North China. ENSO, on the one hand, directly impacts dust activities in North China by modulating the circulation in the Western North Pacific (WNP). Moreover, ENSO enhances the NAO's effect on the North Atlantic SST, explaining their synergistic effects on the dust activities over North China. This study explains the combined role of NAO and ENSO on the dust weather over North China, providing one season ahead signals for the forecast of spring dust activities in North China.

Received: 29 Mar 2024 – Discussion started: 09 Apr 2024

Publisher's note: Copernicus Publications remains neutral with regard to jurisdictional claims made in the text, published maps, institutional affiliations, or any other geographical representation in this preprint. The responsibility to include appropriate place names lies with the authors.

Download & links

Preprint (PDF, 2605 KB)

Notice on discussion status
The requested preprint has a corresponding peer-reviewed final revised paper. You are encouraged to refer to the final revised version.
Preprint (2605 KB)

Download & links

The requested preprint has a corresponding peer-reviewed final revised paper. You are encouraged to refer to the final revised version.

Journal article(s) based on this preprint

25 Sep 2024

Synergistic effects of the winter North Atlantic Oscillation (NAO) and El Niño–Southern Oscillation (ENSO) on dust activities in North China during the following spring

Falei Xu, Shuang Wang, Yan Li, and Juan Feng

Atmos. Chem. Phys., 24, 10689–10705, https://doi.org/10.5194/acp-24-10689-2024,https://doi.org/10.5194/acp-24-10689-2024, 2024

Short summary

Falei Xu, Shuang Wang, Yan Li, and Juan Feng

Interactive discussion

Status: closed

RC1:
'Comment on egusphere-2024-955', Anonymous Referee #1, 22 Apr 2024

General comments

This study investigated the impacts of preceding boreal winter North Atlantic Oscillation (NAO) and El Ni?o-Southern Oscillation (ENSO) on the following spring dust activities over North China during 1980-2022. The authors demonstrated that the significant impacts of NAO and ENSO on the dust activities over North China is only manifested in the negative phases, and discussed the physical mechanism involved to illustrate why the negative phases of NAO and ENSO show a synergistic effect on the following dust events in North China. The message is conveyed clearly and the topic is interesting. The results of this study provide an insight to further understand the dust activities over North China. The conclusions are substantiated based on composite analyses. If published, this work could serve as a valuable reference for dust weather. However, it needs to be minor revised before accepted this paper for publication in ACP with addressing those comments listed below:

Specific comments are as follows:

1.The NAO is a large-scale seesaw in atmospheric mass between the subtropical high and the polar low. It is the dominant mode of atmospheric circulation variability in the North Atlantic sector throughout the year. The definition of the NAO index derived using EOF is commonly employed to depict the variation of NAO. However, the SLP difference between 35°N and 65°N within the Atlantic section is used to define the NAO index. A full comparison of the NAO index is necessary to establish the robustness of result.
2.The authors focus on the relationship between preceding winter NAO and ENSO and dust weather in late spring. The introduction mentions that “the impacts of winter NAO and ENSO on the climate in China is more pronounced” by citing results from previous work. However, it is unclear whether the cross-seasonal impacts also apply when exploring the relationship between NAO, ENSO and dust weather in North China. Therefore, it would be better to provide some references to explain why we should investigate the impacts of previous winter of NAO and ENSO on spring dust weather.
3. In the paper, the authors primarily discuss the effect of NAO and ENSO negative phases on the dust activities over North China. However, given the various phases combinations between these two factors, a more detailed explanation as to why only the negative-negative combinations are considered.
4. In Figures 1-2, the authors illustrate the relationship between NAO, ENSO and dust weather over North China through the spatial distribution of correlation coefficients, and that the relationship is only manifested when NAO and ENSO are in negative phases. A quantitative analysis is needed to further establish the robustness of the result.
5. From Fig 3 and Table 1, it is evident that there are two types when NAO and ENSO are in their negative phases: negative phases of the NAO and ENSO, and negative phases of the NAO and ENSO occurring separately (remove the years with concurrent negative phases of NAO and ENSO). Furthermore, the subsequent composite analyses in the study, focus on the cases with negative phases of the NAO and ENSO. The authors should explain why they have made this choice.
6. In Figs 4 c, f, and i, the variations in the near-surface wind field caused by anomalies of Siberian High, lead to dust emissions from the source areas. However, the depiction of the wind field anomalies appears unclear. It is recommended to modify the Figs to highlight the variations in the wind field.
7. In Table 2, the value of correlation coefficients between the previous winter NATI and spring NATI are similar in scenarios of ENSO- phase (when the negative phase of ENSO occurs alone) and NAO- & ENSO- phase (when the negative phases of both NAO and ENSO co-occur). However, if there exists a synergistic effect of NAO and ENSO on the dust weather, the correlation in the scenario where both NAO and ENSO negative phases co-occur should be higher than when the negative phases of NAO and ENSO occur separately. The authors should have provided a more detailed explanation to clarify this point.
8.The main mechanism for the impact of the winter NAO on the spring dust is the maintenance of the North Atlantic SST anomalies from winter to spring, consistent with previous findings (Chen et al. 2020; Wu and Chen 2020; Song et al. 2022). Several discussions could be added.

Song, L.-Y., et al, 2022: Distinct evolutions of haze pollution from winter to following spring over the North China Plain: Role of the North Atlantic sea surface temperature anomalies. Atmos. Chem. Phys., 22, 1669–1688.

Wu and Chen, 2020: What leads to persisting surface air temperature anomalies from winter to following spring over the mid-high latitude Eurasia?. Journal of Climate, 33, 5861-5883.

Chen et al. 2020: Strengthened connection between springtime North Atlantic Oscillation and North Atlantic tripole SST pattern since the late-1980s. Journal of Climate, 35(5), 2007-2022.
9. There are lots of clerical errors, i.e.,

Line 17-18, sea surface temperatures (SST) in the North Atlantic

Line 220, with regard to the description of the graphs, there may be some errors that

“(b) and (d) As in (a) and (b) ” -> “(c) and (d) As in (a) and (b)”.

The authors should carefully check the whole manuscript.

Citation: https://doi.org/10.5194/egusphere-2024-955-RC1
- AC1: 'Reply on RC1', Fa lei Xu, 12 Jun 2024
  
  The comment was uploaded in the form of a supplement: https://egusphere.copernicus.org/preprints/2024/egusphere-2024-955/egusphere-2024-955-AC1-supplement.pdf
  
  Citation: https://doi.org/10.5194/egusphere-2024-955-AC1
RC2:
'Comment on egusphere-2024-955', Anonymous Referee #2, 27 May 2024
Using multi-reanalysis datasets, the authors investigated the effects of the previous winter NAO and ENSO on the spring dust aerosols over North China. The pronounced influence of NAO and ENSO on dust aerosols was predominantly observed during their negative phases. Furthermore, this analysis examined meteorological conditions, atmospheric dynamics, and wave energy transport, elucidating the synergistic impacts of these negative phases on subsequent dust activities. The findings enhance our understanding of the formation mechanisms of dust events in North China. I recommend that this manuscript be accepted after minor revisions, as this study fits well within the scope of Atmospheric Chemistry and Physics.
Specific comments are as follows:
The study primarily utilizes MERRA-2 reanalysis data for analyzing dust activities over North China. It is essential to assess whether the MERRA-2 data accurately captures dust activities in North China. Please provide further details on the reliability of the reanalysis.

The preceding role of NAO and ENSO on the spring dusty weather over North China is investigated, and it is of interest why the preceding role is focused. And whether their simultaneous role in the dust content is significant or not.

Dust aerosols are important components of atmospheric aerosols, alongside other constituents such as sulfates, nitrogen oxides, black carbon, and so on. Why did the authors choose the dust aerosols in North China as the research objects to be discussed and studied? Please explain and justify this point.

Line 36-37, “The Gobi Desert in East Asia, especially for the Mongolian Plateau and North China, is a major source of dust”. Whether the author is trying to express the meaning of Northern China here, Northern China and North China are two different meanings, please confirm and revise.

Line 77-78, the authors mentioned that “NAO and ENSO often co-occur and have complex interactions”. As well as by citing previous work, the facts of a possible relationship between the two factors are enumerated. However, the authors have not thoroughly explored their relationship. It is suggested that further details be provided to enhance the understanding.

In Figure 3 (a), it is notable that there is a point during the negative phase of the NAO that deviates from the majority of the points, potentially qualifying it as an outlier. If this point is removed from the sequence, it is important to verify whether the relationship between the NAO and dust aerosol content remains robust.

In Figure 5, by describing the precipitation and humidity fields under different scenarios, the authors illustrate the synergistic effect of NAO and ENSO on dust activities in North China. However, the large values of the variables in the graphs do not seem to be well highlighted. Consider modifying the color-coded intervals to enhance the reader's understanding of the section.
Citation: https://doi.org/10.5194/egusphere-2024-955-RC2
- AC2: 'Reply on RC2', Fa lei Xu, 12 Jun 2024
  
  The comment was uploaded in the form of a supplement: https://egusphere.copernicus.org/preprints/2024/egusphere-2024-955/egusphere-2024-955-AC2-supplement.pdf
  
  Citation: https://doi.org/10.5194/egusphere-2024-955-AC2

Interactive discussion

Status: closed

RC1:
'Comment on egusphere-2024-955', Anonymous Referee #1, 22 Apr 2024

General comments

This study investigated the impacts of preceding boreal winter North Atlantic Oscillation (NAO) and El Ni?o-Southern Oscillation (ENSO) on the following spring dust activities over North China during 1980-2022. The authors demonstrated that the significant impacts of NAO and ENSO on the dust activities over North China is only manifested in the negative phases, and discussed the physical mechanism involved to illustrate why the negative phases of NAO and ENSO show a synergistic effect on the following dust events in North China. The message is conveyed clearly and the topic is interesting. The results of this study provide an insight to further understand the dust activities over North China. The conclusions are substantiated based on composite analyses. If published, this work could serve as a valuable reference for dust weather. However, it needs to be minor revised before accepted this paper for publication in ACP with addressing those comments listed below:

Specific comments are as follows:

1.The NAO is a large-scale seesaw in atmospheric mass between the subtropical high and the polar low. It is the dominant mode of atmospheric circulation variability in the North Atlantic sector throughout the year. The definition of the NAO index derived using EOF is commonly employed to depict the variation of NAO. However, the SLP difference between 35°N and 65°N within the Atlantic section is used to define the NAO index. A full comparison of the NAO index is necessary to establish the robustness of result.
2.The authors focus on the relationship between preceding winter NAO and ENSO and dust weather in late spring. The introduction mentions that “the impacts of winter NAO and ENSO on the climate in China is more pronounced” by citing results from previous work. However, it is unclear whether the cross-seasonal impacts also apply when exploring the relationship between NAO, ENSO and dust weather in North China. Therefore, it would be better to provide some references to explain why we should investigate the impacts of previous winter of NAO and ENSO on spring dust weather.
3. In the paper, the authors primarily discuss the effect of NAO and ENSO negative phases on the dust activities over North China. However, given the various phases combinations between these two factors, a more detailed explanation as to why only the negative-negative combinations are considered.
4. In Figures 1-2, the authors illustrate the relationship between NAO, ENSO and dust weather over North China through the spatial distribution of correlation coefficients, and that the relationship is only manifested when NAO and ENSO are in negative phases. A quantitative analysis is needed to further establish the robustness of the result.
5. From Fig 3 and Table 1, it is evident that there are two types when NAO and ENSO are in their negative phases: negative phases of the NAO and ENSO, and negative phases of the NAO and ENSO occurring separately (remove the years with concurrent negative phases of NAO and ENSO). Furthermore, the subsequent composite analyses in the study, focus on the cases with negative phases of the NAO and ENSO. The authors should explain why they have made this choice.
6. In Figs 4 c, f, and i, the variations in the near-surface wind field caused by anomalies of Siberian High, lead to dust emissions from the source areas. However, the depiction of the wind field anomalies appears unclear. It is recommended to modify the Figs to highlight the variations in the wind field.
7. In Table 2, the value of correlation coefficients between the previous winter NATI and spring NATI are similar in scenarios of ENSO- phase (when the negative phase of ENSO occurs alone) and NAO- & ENSO- phase (when the negative phases of both NAO and ENSO co-occur). However, if there exists a synergistic effect of NAO and ENSO on the dust weather, the correlation in the scenario where both NAO and ENSO negative phases co-occur should be higher than when the negative phases of NAO and ENSO occur separately. The authors should have provided a more detailed explanation to clarify this point.
8.The main mechanism for the impact of the winter NAO on the spring dust is the maintenance of the North Atlantic SST anomalies from winter to spring, consistent with previous findings (Chen et al. 2020; Wu and Chen 2020; Song et al. 2022). Several discussions could be added.

Song, L.-Y., et al, 2022: Distinct evolutions of haze pollution from winter to following spring over the North China Plain: Role of the North Atlantic sea surface temperature anomalies. Atmos. Chem. Phys., 22, 1669–1688.

Wu and Chen, 2020: What leads to persisting surface air temperature anomalies from winter to following spring over the mid-high latitude Eurasia?. Journal of Climate, 33, 5861-5883.

Chen et al. 2020: Strengthened connection between springtime North Atlantic Oscillation and North Atlantic tripole SST pattern since the late-1980s. Journal of Climate, 35(5), 2007-2022.
9. There are lots of clerical errors, i.e.,

Line 17-18, sea surface temperatures (SST) in the North Atlantic

Line 220, with regard to the description of the graphs, there may be some errors that

“(b) and (d) As in (a) and (b) ” -> “(c) and (d) As in (a) and (b)”.

The authors should carefully check the whole manuscript.

Citation: https://doi.org/10.5194/egusphere-2024-955-RC1
- AC1: 'Reply on RC1', Fa lei Xu, 12 Jun 2024
  
  The comment was uploaded in the form of a supplement: https://egusphere.copernicus.org/preprints/2024/egusphere-2024-955/egusphere-2024-955-AC1-supplement.pdf
  
  Citation: https://doi.org/10.5194/egusphere-2024-955-AC1
RC2:
'Comment on egusphere-2024-955', Anonymous Referee #2, 27 May 2024
Using multi-reanalysis datasets, the authors investigated the effects of the previous winter NAO and ENSO on the spring dust aerosols over North China. The pronounced influence of NAO and ENSO on dust aerosols was predominantly observed during their negative phases. Furthermore, this analysis examined meteorological conditions, atmospheric dynamics, and wave energy transport, elucidating the synergistic impacts of these negative phases on subsequent dust activities. The findings enhance our understanding of the formation mechanisms of dust events in North China. I recommend that this manuscript be accepted after minor revisions, as this study fits well within the scope of Atmospheric Chemistry and Physics.
Specific comments are as follows:
The study primarily utilizes MERRA-2 reanalysis data for analyzing dust activities over North China. It is essential to assess whether the MERRA-2 data accurately captures dust activities in North China. Please provide further details on the reliability of the reanalysis.

The preceding role of NAO and ENSO on the spring dusty weather over North China is investigated, and it is of interest why the preceding role is focused. And whether their simultaneous role in the dust content is significant or not.

Dust aerosols are important components of atmospheric aerosols, alongside other constituents such as sulfates, nitrogen oxides, black carbon, and so on. Why did the authors choose the dust aerosols in North China as the research objects to be discussed and studied? Please explain and justify this point.

Line 36-37, “The Gobi Desert in East Asia, especially for the Mongolian Plateau and North China, is a major source of dust”. Whether the author is trying to express the meaning of Northern China here, Northern China and North China are two different meanings, please confirm and revise.

Line 77-78, the authors mentioned that “NAO and ENSO often co-occur and have complex interactions”. As well as by citing previous work, the facts of a possible relationship between the two factors are enumerated. However, the authors have not thoroughly explored their relationship. It is suggested that further details be provided to enhance the understanding.

In Figure 3 (a), it is notable that there is a point during the negative phase of the NAO that deviates from the majority of the points, potentially qualifying it as an outlier. If this point is removed from the sequence, it is important to verify whether the relationship between the NAO and dust aerosol content remains robust.

In Figure 5, by describing the precipitation and humidity fields under different scenarios, the authors illustrate the synergistic effect of NAO and ENSO on dust activities in North China. However, the large values of the variables in the graphs do not seem to be well highlighted. Consider modifying the color-coded intervals to enhance the reader's understanding of the section.
Citation: https://doi.org/10.5194/egusphere-2024-955-RC2
- AC2: 'Reply on RC2', Fa lei Xu, 12 Jun 2024
  
  The comment was uploaded in the form of a supplement: https://egusphere.copernicus.org/preprints/2024/egusphere-2024-955/egusphere-2024-955-AC2-supplement.pdf
  
  Citation: https://doi.org/10.5194/egusphere-2024-955-AC2

Peer review completion

AR: Author's response | RR: Referee report | ED: Editor decision | EF: Editorial file upload

AR by Fa lei Xu on behalf of the Authors (12 Jun 2024) Author's response Author's tracked changes Manuscript

ED: Reconsider after major revisions (21 Jun 2024) by Marco Gaetani

Dear Authors,
I first thank you for your timely and comprehensive response to the reviewers’ comments. After careful evaluation, I believe that your response and the manuscript itself still shows some issues that need to be fixed. Please find below my comments. I encourage you to revise and resubmit an improved version of the manuscript.

General comment to Response to reviewers:
Please clearly highlight which paragraphs are new or modified in the revised version. Moreover, line numbers should be referred more accurately.

Specific comments to Response to reviewers:

Response to R1:

Comment 1: The paragraph on NAOIs comparison reported here does not match with the revised version of the manuscript. Please: 1) modify the revised manuscript accordingly; 2) provide a reference to the source of data you use for the comparison.

Comment 2: The analysis shown in Fig. R5 could be added to the main text, to justify the choice of analysing DJF vs MAM.

Comment 6: The paragraph reported here does not match with the revised version of the text, please modify accordingly. Also, the figure is not very much improved, please try to reduce the number of plotted vectors and increase the size.

Response to R2:

Comment 1: The comparison between MERRA and the Dust Index might be included in the manuscript.

Comment 4: It is not clear the difference in the notations North and northern China: please elaborate more the response, and modify the manuscript accordingly.

General comments to the manuscript:

1. Significance level should be homogeneous through the text, and set to 0.05. You could set an additional threshold at 0.10, defining weak significance. P-value at 0.2 is too low, and cannot be used to define statistical significance. Furthermore, computing correlations for 7-year time series (negative NAO & ENSO) is questionable. I recommend to revise the whole correlation analysis and adjust your discussion and conclusions accordingly.

2. The use of correlation and composite analysis is not very clear to me. On the one hand, when computing correlations during negative phases of NAO/ENSO, you are assessing the impact of negative phases of different magnitude on the dust content/atmospheric variables/SST, i.e., you are studying the variability of the relationship. On the other hand, when computing composites, you are assessing the overall impact of the negative phases, i.e., you are studying the impact on the mean values. The specific objectives of these two complementary approaches should be clarified.

3. English language needs a deep revision.

Specific comments to the manuscript:

Line 10: “by impacting”.

Line 11: “Based on the atmospheric and oceanic datasets during 1980-2022…” please rephrase.

Line 14: “exert significant effects in influencing…” please rephrase.

Lines 13-17: These two sentences redundant, please rephrase.

Line 18: “associated”.

Line 18: “Owing to the persistence of SST…” please rephrase.

Line 24: What is “dust weather”? Here and across the text.

Line 39: What is “dust disasters”? Here and across the text.

Lines 110-117: There are many redundancies in this paragraph, please rephrase to streamline it.

Line 141: Please define how the last winter of your time series is defined.

Lines 143-144: By removing the linear trend, you are not “enhancing the investigation of the NAO-ENSO-dust relationship”, you are actually focusing your analysis on the interannual variability. Please rephrase.

Line 155: Why is ENSO defined in the period 1980-2022?

Line 192: How these correlation coefficients are computed?

Figure 1: What do the green lines represent? Same comment for Figures 2 and 5.

Figure 3: Panel (c) is rather puzzling: from Table 1 we see that there are three possible situations, that is negative NAO (15 years), negative ENSO (16 years), negative NAO and ENSO (7 years). So, I don’t understand what the white bars represent (and why they are different from the green one). Please clarify in the caption and in the text. Can you also add uncertainty bars to the plot?

Line 262: How do you estimate this value? Is it just an approximate value you derive from the map? Do you compute a spatial average? Same comments for Lines 264 and 270.

Line 270: In comparing the zonal wind anomalies, do you assess statistical significance? Specifically, +3 m/s anomaly is significantly stronger than +1.5 and +2.5 m/s?

Line 274: Same comments for this paragraph: 1) How geopotential anomalies are estimated? 2) Significance in the differences has been estimated?

Figures 4 and 5: Please add a box to highlight your study region.

Line 370: Why Figure 7 is mentioned before Figure 6?

Line 374: What is the rationale of the NATI definition? The SST patterns in Figure 6 resembles very much to a positive Atlantic Multidecadal Oscillation phase.

Figures 8, 9 and 10: Please explain why regression fields are multiplied by -1.

Hide

AR by Fa lei Xu on behalf of the Authors (08 Jul 2024) Author's response Author's tracked changes Manuscript

ED: Publish subject to minor revisions (review by editor) (17 Jul 2024) by Marco Gaetani

Dear Authors,
many thanks for considering my comments and suggestions, the manuscript is now in a much better shape. However, some issues still need to be addressed before final acceptance. In particular:
- Setting the threshold for statistical significance to p=0.10 resulted in a reduction of overall significance of your results. Therefore, 1) the discussion of some figures should be adjusted to the new results; 2) the overall low statistical significance of the results should be highlighted and discussed in the conclusions.
- English still needs to be improved, there are still many typos and mistakes, odd expressions and some sentences don’t read fluently. I recommend a further deep revision of the language.
Please find below my specific comments.

L21: WNP is not used elsewhere in the abstract, please remove it.

L52: westerly belt, do you mean the mid-latitude westerly regime?

Figure 1: how do you get a spatialised map from station data? Did you apply any spatialisation technique? Please clarify. Also specify the unit for DI.

L137: “overall consistent”.

L149: please clarify in the text whether winter 2022 is defined from December 2021 or December 2022.

L161: NAOI from Hurrell and Jones have been used to validate the NAOI by Li and Wang.

L166: the justification for focusing on previous winter is given in Sec. 3.1. Here you can just tell how seasonal means are computed.

L195: please revise the definitions: p should be pressure and U should be U=(U, V, 0) (you need a 3D vector wind for a 3D formulation). What is the difference between f0 and f? What is N? what is z?

L202: NAO std actually peaks in February.

Figure 2: I’m wondering why, being the NAOI standardised, the std in panel (a) shows such high values. Shouldn’t be around 1 on an annual basis? As shown by the ENSO index in panel (b).

L230: are the correlation coefficients significant?

Figure 3: panels (a) and (b) are the same as in Fig. 2, please remove them and modify caption and text accordingly.

L260: please provide information about the significance of correlations.

L262: what do you mean by correlation distribution? Is it not just correlation?

L263: please provide information about correlation coefficients and significance.

L264: ENSO in brackets is confusing, please rephase in a more readable way.

Figure 5: thanks for improving the description of the figure, which is now much clearer. I also think that error bars are no longer necessary (I apologise for changing my mind on that, it’s just that I couldn’t understand the plot). I rather suggest that you provide information about the statistical significance of the SDI in the different cases. Specifically: NAO vs NAO-; ENSO vs ENSO-; NAO vs NAO&ENSO; ENSO vs NAO&ENSO.

L309: zonal wind is stronger in NAO&ENSO case wrt the NAO- case, but not so clear wrt the ENSO- case. You should provide robust evidence, or mitigate this claim.

Figure 7: after the change in the significance level, this figure is now problematic. The NAO- case show no significant anomalies, while ENSO- and NAO&ENSO cases only show significant anomalies north west of North China, and no significant anomalies in North China. You should modify the discussion of this figure in the light of the new results.

L415: Figures 8bc don’t show the SDI-NATI correlation, but the SDI-SST correlation.

L416: where do we see the significant relationship between SDI and NATI?

L429: please provide significance for the correlations.

Figure 10g-i: the first impression here is that the correlation pattern is not stronger than in the NAO- and ENSO- cases. You should provide quantitative evidence, or mitigate the claim at L481-485.

Figures 10, 11 and 12: you should explain (in the caption) why regressions fields are multiplied by -1.

Figures 10 and 12: please display North China.

Section 4: please discuss in this section the limitations associated with the overall low statistical significance of your results.

L541: please avoid using acronyms that you don’t use much in this section, e.g. WNP, SH.

L573: please clarify how “the availability of dataset” affects the study of the interdecadal variability.

L587: this last sentence could be moved to the discussion of the interdecadal variability above.

Hide

AR by Fa lei Xu on behalf of the Authors (23 Jul 2024) Author's response Author's tracked changes Manuscript

ED: Publish subject to technical corrections (07 Aug 2024) by Marco Gaetani

AR by Fa lei Xu on behalf of the Authors (08 Aug 2024) Manuscript

Journal article(s) based on this preprint

25 Sep 2024

Synergistic effects of the winter North Atlantic Oscillation (NAO) and El Niño–Southern Oscillation (ENSO) on dust activities in North China during the following spring

Falei Xu, Shuang Wang, Yan Li, and Juan Feng

Atmos. Chem. Phys., 24, 10689–10705, https://doi.org/10.5194/acp-24-10689-2024,https://doi.org/10.5194/acp-24-10689-2024, 2024

Short summary

Falei Xu, Shuang Wang, Yan Li, and Juan Feng

Viewed

Total article views: 384 (including HTML, PDF, and XML)

HTML	PDF	XML	Total	BibTeX	EndNote
296	61	27	384	15	13

HTML: 296
PDF: 61
XML: 27
Total: 384
BibTeX: 15
EndNote: 13

Views and downloads (calculated since 09 Apr 2024)

Month	HTML	PDF	XML	Total
Apr 2024	122	20	10	152
May 2024	69	16	7	92
Jun 2024	38	11	8	57
Jul 2024	31	5	2	38
Aug 2024	24	5	0	29
Sep 2024	12	4	0	16

Cumulative views and downloads (calculated since 09 Apr 2024)

Month	HTML	PDF	XML	Total
Apr 2024	122	20	10	152
May 2024	69	16	7	92
Jun 2024	38	11	8	57
Jul 2024	31	5	2	38
Aug 2024	24	5	0	29
Sep 2024	12	4	0	16

Viewed (geographical distribution)

Total article views: 367 (including HTML, PDF, and XML) Thereof 367 with geography defined and 0 with unknown origin.

Country	#	Views	%

Latest update: 25 Sep 2024

Download

The requested preprint has a corresponding peer-reviewed final revised paper. You are encouraged to refer to the final revised version.

Preprint (2605 KB)
Metadata XML

Short summary

This study examines how the North Atlantic Oscillation (NAO) and El Niño-Southern Oscillation (ENSO) in the previous winter affect spring dust activities in North China. The results show that NAO and ENSO, particularly in their negative phases, greatly influence dust activities. When both NAO and ENSO are negative, their combined effect on dust activities is even greater. This research underscores the importance of these climate patterns in predicting spring dust activities in North China.


Total:	0
HTML:	0
PDF:	0
XML:	0