the Creative Commons Attribution 4.0 License.
the Creative Commons Attribution 4.0 License.
Intense rains in Israel associated with the train effect
Uri Dayan
Lidiya Shendrik
Elyakom Vadislavsky
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- Final revised paper (published on 26 Sep 2024)
- Preprint (discussion started on 02 Jan 2024)
Interactive discussion
Status: closed
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RC1: 'Comment on nhess-2023-215', Anonymous Referee #1, 28 Jan 2024
General comments:
This paper summarizes the results of a well designed and well carried out study into the characteristic dynamical feature associated with a “Train Effect” phenomenon in the eastern Mediterranean during winter. The authors identify the main dynamical features associated with the a train of precipitating convective cells moving from sea to land in the southern coastal region of Israel and compare and contrast them to features identified in previously studied train effect in the U.S. summer.
The paper can benefit from editing to improve its presentation quality by attending to grammatical and sentence structure errors. I indicated some of those below.
Specific comments (in order of appearance in the text):
- Page 1, line 18: “yield ~35 mm rainfall”. Here and in the paper text the authors refer to rain amounts and it is not clear if the numbers imply rain rate (i.e., about per unit time) of the amount of precipitation falling over the entire life time of the phenomenon. I suggest being more specific regarding the values given here and in other cases in the text.
- Page 1, lines 29-30: Where is the sentence part put in quotes taken from (citation is missing)?
- Page 4, line 112: “characterized AS A Mediterranean-TYPE climate”, can you provide reference for “Mediterranean-type Climate”?
- Page 4, lines 119-121: “persisted 3.5 hours and generated heavy rain, with a maximum of > 60 mmh -1(as inferred from Fig. 3a-e), summing up to > 60 mm for the entire event (Fig. 3f). The integrated rainfall during the event exceeded 40 mm along the train.” The numbers don’t’ make sense to me.
- Page 9, sentence on lines 184-187: This is confusing. In Fig 4A the train is south of the maximum wind, i.e., to the right of it. The situation is different in Fig. 4b, where the train is on the left. So the relation of the train to the maximum wind depends on the level of the wind, right?
- Page 11, lines 228-29: So there is a common dynamical element between the two phenomena?
Editorial comments:
Page 2, line 43: in reference to the LLJ - change “tend” to “tends”.
Page 2, line 46: “in the form of A train” (missing “a”) or “in the form of TRAINS” (in plural).
Page 2, line 50: “Heavy rains …….. HAVE been identified”
Page 2, line 53: “convergence of A land breeze.” (Missing “a”) or “convergence of land BREEZES.” (Refer to the land grease phenomenon in plural.
Page 2, line 54: “convergence between A southerly land-breeze”
Page 3, line 68: “took THE lives of 10 people.
Page 3, line 73: “and ATEMPS to generalize”
Page 3, line 77: “The rain data ARE”
Page 3, line 77: “with 200-270 mm” - over what time interval? The entire time span of the phenomenon?
page 4, line 117: 60 mm over what time?
Page 4, lines 117-118: “form of A train”
Page 4, line 122: “ON the order of” (same on page 5 line 131).
Page 6, line 148: Use “included in the study” instead of “composing the study”
Page 7, line 155: Use “orientation was around” instead of “orientation is around” (past tense fits better with the previous and following sentences).
Page 7, line 130: “which IMPLIES a high potential”
Page 10, line 211: Instead of using “the factors are irrelevant” ), i.e., as if there are factors like that here and they are not material, I suggest stating that: “The factors relevant for EM trains are different”
Page 11, line 220: Instead of using the terms “left flank” or “right flank” here and before why not use more geographical term such as “north flank” and “south flank”?
Citation: https://doi.org/10.5194/nhess-2023-215-RC1 -
AC1: 'Reply on RC1', Baruch Ziv, 28 May 2024
Specific comments (in order of appearance in the text) our responses follow the individual comments.
- Page 1, line 18: “yield ~35 mm rainfall”. Here and in the paper text the authors refer to rain amounts and it is not clear if the numbers imply rain rate (i.e., about per unit time) of the amount of precipitation falling over the entire life time of the phenomenon. I suggest being more specific regarding the values given here and in other cases in the text.
In the first time when appears, we shall note that rainfall refers to total amount (mm) over the pertinent period, and when rain rate is considered, we shall use only this term, in mm/h units.
- Page 1, lines 29-30: Where is the sentence part put in quotes taken from (citation is missing)?
The source is Doswell 1996, who is quoted one sentence below. For the sake of clarity, we shall move it to the end of this quotation.
- Page 4, line 112: “characterized AS A Mediterranean-TYPE climate”, can you provide reference for “Mediterranean-type Climate”?
We shall add "type" and refer it to Koeppen classification, together with the standard notation, "Cs", and quote: "Köppen, Wladimir (1884). Translated by Volken, E.; Brönnimann, S. "Die Wärmezonen der Erde, nach der Dauer der heissen, gemässigten und kalten Zeit und nach der Wirkung der Wärme auf die organische Welt betrachtet" [The thermal zones of the earth according to the duration of hot, moderate and cold periods and to the impact of heat on the organic world)]. Meteorologische Zeitschrift (published 2011). 20 (3): 351–360. Bibcode:2011MetZe..20..351K. doi:10.1127/0941-2948/2011/105", also in the reference list.
- Page 4, lines 119-121: “persisted 3.5 hours and generated heavy rain, with a maximum of > 60 mmh -1(as inferred from Fig. 3a-e), summing up to > 60 mm for the entire event (Fig. 3f). The integrated rainfall during the event exceeded 40 mm along the train.” The numbers don’t’ make sense to me.
Thank you for this comment. The corrected sentence will be: “persisted 3.5 hours and generated heavy rain, with a maximum rate of > 60 mmh-1 (as inferred from Fig. 3a-e), summing up to 60 mm rainfall for the entire event (Fig. 3f).”
- Page 9, sentence on lines 184-187: This is confusing. In Fig 4A the train is south of the maximum wind, i.e., to the right of it. The situation is different in Fig. 4b, where the train is on the left. So the relation of the train to the maximum wind depends on the level of the wind, right?
Thank you for your valuable comment. The location of the train is left of the maximum wind at the lower level (925 hPa, Fi.4b), and, indeed, not at 700 hPa (Fig. 4a). Actually, the train location in 700 hPa is along the maximum wind, which is less pronounced there than in the lower level. Following your comment, we shall stress that the forcing for the train formation exists in the lower–levels. We shall add this point in the revised manuscript.
- Page 11, lines 228-29: So there is a common dynamical element between the two phenomena?
As a matter of fact, there is a common dynamic element between the 'cold' train studied here and the 'warm' trains previously studied. The common element is the stationarity in the synoptic configuration, i.e., both the cold front, responsible for the warm train, and the southern boundary of the CL, for the cold train, are quasi-stationary. We shall add this Table 2..
Editorial comments:
We accept them all, and will correct the text accordingly after receiving all editorial comments from the other referees.
Page 2, line 43: in reference to the LLJ - change “tend” to “tends”.
Page 2, line 46: “in the form of A train” (missing “a”) or “in the form of TRAINS” (in plural).
Page 2, line 50: “Heavy rains …….. HAVE been identified”
Page 2, line 53: “convergence of A land breeze.” (Missing “a”) or “convergence of land BREEZES.” (Refer to the land grease phenomenon in plural.
Page 2, line 54: “convergence between A southerly land-breeze”
Page 3, line 68: “took THE lives of 10 people.
Page 3, line 73: “and ATEMPS to generalize”
Page 3, line 77: “The rain data ARE”
Page 3, line 77: “with 200-270 mm” - over what time interval? The entire time span of the phenomenon?
page 4, line 117: 60 mm over what time?
Page 4, lines 117-118: “form of A train”
Page 4, line 122: “ON the order of” (same on page 5 line 131).
Page 6, line 148: Use “included in the study” instead of “composing the study”
Page 7, line 155: Use “orientation was around” instead of “orientation is around” (past tense fits better with the previous and following sentences).
Page 7, line 130: “which IMPLIES a high potential”
Page 10, line 211: Instead of using “the factors are irrelevant” ), i.e., as if there are factors like that here and they are not material, I suggest stating that: “The factors relevant for EM trains are different”
Page 11, line 220: Instead of using the terms “left flank” or “right flank” here and before why not use more geographical term such as “north flank” and “south flank”?
Citation: https://doi.org/10.5194/nhess-2023-215-AC1
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CC1: 'Comment on nhess-2023-215', Hadas Saaroni, 25 Apr 2024
Attached are my comments on the manuscript nhess-2023-215.
I wish to be an anonymous referee.
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AC3: 'Reply on CC1', Baruch Ziv, 28 May 2024
Major Comments
- The study included 17 events out of 30 identified. It is essential to refer to the 13 events that were not investigated and explain why they were not investigated. It must be explained whether they represent a different phenomenon or dynamic process, which may change the insights, or whether they were less prominent in their characteristics.
We separated the 17 cases from the other 13, since they have a distinct dynamic mechanism in common. This is related to a band of maximum wind identified at the periphery of the cyclone, which delineates its rainy sector, being the the subject of the paper. The other cases, which could not be attributed neither to the same mechanism, nor to any other common one, were excluded.
- The authors note that based on previous studies: "the train effect is associated with quasistationary cold fronts or within pre-frontal warm tongues…” (line 39). The dynamic factors and process leading to the formation of trains associated with quasi-stationary cold fronts in the cold front must be explained, this is to distinguish it from the different dynamical factors associated with Cyprus Lows.
Both trains, these associated with cold fronts (including the pre-frontal ones) and the trains analyzed in the present paper, are composed of convective clouds that develop within unstable air. The difference between the two categories of trains lies in the identity of the factor initiating the ascendance. For the trains associated with fronts, the factor is buoyancy due to temperature difference across the front, whereas the initial ascendance for the trains, analyzed in this study, is forced by lower-level convergence. We shall note this in both the introduction, concerning the frontal trains, and in the discussion, in the comparison between the two types of trains.
Specific comments:
Page 2, lines 43-44: the authors mention "Train effect was identified also in Western Europe, near the western Mediterranean". Be more specific about the location.
To be done.
Page 2, lines 45-46: “ZAMG (2014) analyzed 100 convective systems during the period 1992 – 2009…”. Specify the location of this study.
To be done.
Page 2, line 55: “from the North African coast…” change to: “from the North African and North Sinai Desert coasts…”
To be done.
Page 2, line 57: “…the rain produced by this type of system lasts 20 hours…” For the sake of clarity specify which type of system he refers to.
We shall replace the phrase "this type of system lasts" by "these coastal fronts last".
Page 2, line 67: “…within the cold sector of a CL in 2018.” Add April 2018 and stress that 'cold trains' occur not only in the mid-winter but also during spring.
To be corrected.
Page 3, line 70: “…to document trains”. I recommend changing to “… identify, document and analyze…”
To be done.
Page 3, line 76: “…four consecutive winters (December-February) of the years 2018-2022 (except January-February 2019 due to missing radar data).” Change to: “…four consecutive mid-winters (December-February) of the years 2018-2022 (except January-February 2019 due to missing radar data), total of 10 months.”
To be done.
Page 3, lines 80-83: Why did the authors utilized data with high resolution, of 0.1, and did not use the ERA5 data of 0.25 resolution?
We had tried to use the ERA5 with 0.25° resolution, but could not identify clearly the signature of the trains neither in the rain field, nor in the vertical velocity field. We shall add a notation for that.
Page 4, line 112: “characterized by Mediterranean climate”. Please specify what are the characteristics of t1his type of climate and add a citation.
Following your and referee #1 comment (and suggestion), we shall add "type" and refer it to Koeppen classification, together with the standard notation, "Cs", and quote: "Köppen, Wladimir (1884). Translated by Volken, E.; Brönnimann, S. "Die Wärmezonen der Erde, nach der Dauer der heissen, gemässigten und kalten Zeit und nach der Wirkung der Wärme auf die organische Welt betrachtet" [The thermal zones of the earth according to the duration of hot, moderate and cold periods and to the impact of heat on the organic world)]. Meteorologische Zeitschrift (published 2011). 20 (3): 351–360. Bibcode:2011MetZe..20..351K. doi:10.1127/0941-2948/2011/105", also in the reference list.
Page 4, line 112: “The rainiest area was the coastal plain, with 200-270 mm…”. State how long this amount of rain accumulated and state the ratio between the amount that fell as a product of the trains (see line 120) and the total rainfall depth.
See our response to the next comment.
Page 4, line 120: “…summing up to > 60 mm for the entire event”. Were there other trains that were not identified or investigated? I recommend referring to the existence of parallel trains.
Thank you for drawing our attention to the mistakes. We found out that we wrote erroneously that the train lasted for 3.5 hours, whereas it lasted 2.5 hours. The part "This system persisted 3.5 hours .. the entire event (Fig. 3f). The integrated rainfall during the event exceeded 40 mm along the train" will be rephrased as follows: "This system persisted 2.5 hours and generated heavy rain, with a local maximum of > 60 mmh-1 (as inferred from Fig. 3a-e). The integrated rainfall during the event exceeded 40 mm along the train (Fig. 3f). Another train occurred over the region in the previous day (Table 1, No, 1) and yielded an average rainfall of 50 mm (not shown). This implies that the two trains contributed ~35% of the total rainfall obtained over the coastal plain during the 3 days of the rainstorm.
Page 5, lines 136-137: “…was developed within a homogeneous air-mass”. Recommend changing to: “…was developed within a homogeneous cold air-mass”.
To be done.
Page 5, line 138: “…indicate that the CL was at its occluded phase.” I recommend adding a sentence (here or in the discussion section) that explains the difference from the quasistationary cold front, mentioned in the introduction section.
The homogeneous temperature field over the eastern rranean, as seen in Figs. 2b and 4c, and described in the text (see lines 137 and 173) indicates that the situation is not related to frontal activity.
Page 7, lines 161-162: “In 13 of the 17 events, no rain was observed to the right (south) of the train.” And in the other four events, was there a difference in precipitation activity?
We agree with you, and shall add in line 162, after ".. of the train." The following sentence: "Also, in the remaining four events, the rain activity south of the train was much weaker than to the north of it."
Page 8, Table 1: titles: add N to the Lat and E to the Lon.
To be done.
Page 8, Table 1: It is recommended to add the standard deviation in addition to displaying the average only.
Standard deviations will be added.
Page 9, Fig. 4: After a thorough inspection I have noticed that the location of the train left of the maximum wind takes place only on the lower level (925-hPa level). Please, point to the fact that the mechanism responsible for the train originates from the below. Moreover, the figure will become clearer if you add notation of the pressure-level on each part of it. Also, why is the temperature (or temperature anomaly) plot not shown at the 850-hPa level and the 500-hPa GPH and vorticity, as shown in Figure 2?
Thank you for your valuable comment. We shall replace the 925-hPa temperature field by the 850-hPa. Also, the 700 hPa wind chart will be replaced by the 500-hPa relative vorticity and wind field. This map shows a contrast between positive vorticity north of the train and negative to its south. This demonstrates that the trains denote the southern border of the cyclonic core of the upper-level trough. Unlike the lower-levels, where the train is found left of the maximum wind, the vorticity gradient in the upper-level implies that the train there is co-located with the core of maximum wind. The above will be included in the revised manuscript.
We shall also add notations of the pressure levels and field variables on the various parts of the figure.
Page 10, Fig. 5: For the sake of clarity, I suggest adding notation of the pressure-level and atmospheric variable in parts a and b.
We agree with you, and shall do it.
Page 11, line 234: “…show an average significant height of 3-4 meters, with an average maximum of 5-6 meters”. A citation is needed.
Thank you for notifying us for that. The source is the "Coastal and Marine Engineering Research Institute Ltd (CAMERI)" in Israel (https://www.cameri-eng.com/). We shall cite them.
Page 12, lines 264-265: “…a small frequency compared to the 17 train events...” Shouldn’t it be 30 events?
We referred to the 17 events alone, because only these were found to have affinity with the coastal fronts, and hence were candidates for comparison with the latter.
Typographical errors:
We accept them all, and will correct the text accordingly after receiving all editorial comments from the other referees.
Page 1, line 19: change EM trains to East Mediterranean trains
Page 1, line 27: Saaroni et al 2011 should be corrected to Saaroni et al. 2010 and Sandler et al. 2023 should be corrected to Sandler et al.2024.
Page 1, line 32: delete the sign ‘ after the word mostly. Page 2, line 43: Change “tend” to “tends”.
Page 2, line 45: Change "in the form of train" to "in the form of trains".
Page 2, line 46: “in the form of A train” (missing “a”) or “in the form of TRAINS” (in plural).
Page 2, line 50: Change "train effect has been…" to “train effect have been”.
Page 3, line 68: Change “took lives of 10 people” to “took the lives of 10 people”.
Page 3, line 71: Change "attempt" to "attempts".
Page 3, line 77: “The rain data is based" to "The rain data are based”.
Page 3, line 87: Change "These are regarded" to "These are regarded as".
Page 3, line 94: Change "modified as to fit" to " modified to fit".
Page 3, line 95: Change "location of the CLs' centers" to "locations of the CLs' centers".
Page 5, line 134: Change "the cloud were stirred" to "the clouds were stirred".
Page 6, line 149: Change "5 of them are" to "5 of them were".
Page 7, line 157: Change "while these associated" to "while those associated".
Page 7, line 159: Change "flashflood" to "flash flood".
Page 11, line 228: Change "that produce this" to "that produces this".
Page 12, line 240, caption of Fig. 6: add the word Desert after Sinai so it will be “Sinai Desert”.
Page 12, line 256: “… as is reflected in 925 hPa” Should be changed to: “as is reflected in the 925-hPa temperature map”.
Page 13, line 269: Cl should be corrected to CL.
Page 13, line 272: Change "ingredient the CL" to "ingredient of the CL".
Lines 35, 40, 229: Change Chappel to Chappell.
Lines 31, 38, 229: Doswell 1996 should be changed to Doswell et al. 1996. Delete the comma after the author’s name in the following citations: L. 31: Doswell et al. 1996; L. 35: Chappell 1986; L. 41: Corfidi 2003; L. 77: Alpert et al. 2004; L. 80: Haiden et al. 2011; L. 83: Hólm et al. 2016; L. 92: Sinclair and Revell 2000; L. 114: IMS publication 2018.
Page 14, line 316: delete the reference of Alpert et al. (1990) since it does not appear in the text.
Page 14, lines 323-324: The link to Chappell (1986) cannot be found and should be: https://link.springer.com/chapter/10.1007/978-1-935704-20-1_13
Page 15, line 364: The reference of Saaroni et al should be 2010 (and not 2011). Page 15, line 365: The reference of Schwartz et al. (1990) should be moved after the reference of Sandler et al.
Page 15, line 368: The reference of Sandler et al., should be moved before Schwartz et al. (1990), and it needs to be corrected to: Sandler, D., Saaroni, H., Ziv, B., Hochman, A., Harnik, N. and Rostkier-Edelstein, D: A multiscale approach to statistical downscaling of daily precipitation: Israel as a test case, Int. J. Climatol., 44(1), 59-71, 2024. https://doi.org/10.1002/joc.8315
Citation: https://doi.org/10.5194/nhess-2023-215-AC3
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AC3: 'Reply on CC1', Baruch Ziv, 28 May 2024
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RC2: 'Comment on nhess-2023-215', Anonymous Referee #2, 29 Apr 2024
General comments:
In general, I think this is an interesting study to explore the dynamics of the “cold train” phenomena over the eastern Mediterranean region. This research could provide more insight into the causes of high impact weather event in the region. There are several places where additional explanations might be needed to increase clarity and readability. I recommend minor revision.
Specific comments:
Lines 81-84: Is there any reason this dataset is used instead of ERA5?
Lines 85-89: It might be useful to include a schematic diagram to better illustrate how this is defined in the current study.
Lines 92-94: I am a bit confused here. What is the “reference point” (e.g. is it “train”-centred?) of these transformations? For example, how do the authors know how much should an atmospheric field need to rotate/scale/move?
Fig. 2: I was originally a bit puzzled by the red line as the train but then when I saw Fig. 3f, it makes perfect sense. Would the authors consider moving Fig. 3f to Fig. 2?
Lines 156-158: The authors suggested that there is a positive relation between longitude of the cyclone center and the train orientation. However, it is not very clear to me whether this is the case. Perhaps the author could show the result of correlation analysis to support their statement?
Lines 160-162: I think it might be worthwhile to include some figures in the supplementary to support these statements, e.g. overlay of 925 hPa GPH and precipitation of those events.
Table 1: Perhaps the event entries should be in chronological order (event no. 15 and 16).
Section 4:
- It would be better to separate Summary and discussion. It is because certain core ideas of this study only appear in this section (and in the abstract), which should have been discussed in earlier sections. E.g. the notion of cold trains and warm trains only appears in the abstract and in Section 4. The authors should introduce such notion in the introduction to increase readability. Furthermore, the dynamical framework of “cold train” is one of the core results of this study. This alone deserves its own section.
- [related to introduction] In the introduction, the authors should explicitly indicate the existing “warm train” model could not explain the “train” observed over EM. Then this section would make more sense.
Lines 231-236: I am a bit confused. At the beginning of the paragraph, it seems that “friction exerted by the sea surface” is not a contributing factor but at the end it appears to suggest that it is?
Figure 6: What level(s) of pressure, wind, etc are shown in the figure?
Lines 269-274: Could this research be applied to improve nowcasting/short-range forecast?
Appendix A: This section is not mentioned in the main text. Since it is related to the train formation, perhaps the authors should consider including this section in the main text rather than in the appendix.
Citation: https://doi.org/10.5194/nhess-2023-215-RC2 -
AC2: 'Reply on RC2', Baruch Ziv, 28 May 2024
Specific comments:
Lines 81-84: Is there any reason this dataset is used instead of ERA5?
We had tried to use the ERA5 with 0.25° resolution, but could not identify clearly the signature of the trains neither in the rain field, nor in the vertical velocity field. We shall add a notation for that.
Lines 85-89: It might be useful to include a schematic diagram to better illustrate how this is defined in the current study.
Actually, the schematics appears in full in Fig. 6. But, for better clarity, we shall refer the reader to Figs. 1 and 2a, where Cyprus Lows will be denoted. For this end, we shall change the caption of Fig. 1 and denote the cyclone center in Fig. 2a.
Lines 92-94: I am a bit confused here. What is the “reference point” (e.g. is it “train”-centred?) of these transformations? For example, how do the authors know how much should an atmospheric field need to rotate/scale/move?
The individual maps were transformed to bring them to a common basis, so that in each one the cyclone center would be north of the train center, 500 Km appart. The first step was to rotate each map about the location of the cyclone's center (which served as a 'reference point') by an angle equal (and opposite) to the deviation of the orientation of the line joining the train center with the cyclone center from the south-north direction. The 2nd step was to rotate the wind direction accordingly in every grid point. The third was to stretch (or contract) the grid so as to bring the distance between the train and the cyclone center to 500 Kn.
In the revised version we shall modify the description to make these points clearer.
Fig. 2: I was originally a bit puzzled by the red line as the train but then when I saw Fig. 3f, it makes perfect sense. Would the authors consider moving Fig. 3f to Fig. 2?
Thank you for your suggestion. We shall do it.
Lines 156-158: The authors suggested that there is a positive relation between longitude of the cyclone center and the train orientation. However, it is not very clear to me whether this is the case. Perhaps the author could show the result of correlation analysis to support their statement?
First of all, we shall add the correlation, which is 0.41, confident at the 0.10 Level. For the reader convenience, the relevant columns in Table 1 will appear side by side.
Lines 160-162: I think it might be worthwhile to include some figures in the supplementary to support these statements, e.g. overlay of 925 hPa GPH and precipitation of those events.
Our finding concerning the absence of rain south of the trains is based on the radar images. We derived maps that combine the integrated radar data (as shown in Fig. 3f), with their limited areal coverage, and the 925 GPH maps, covering the Levant region, which reflect the synoptic context. We shall include a matrix of 4 maps like this in the revised paper.
Table 1: Perhaps the event entries should be in chronological order (event no. 15 and 16).
Thank you. It will be corrected.
Section 4:
- It would be better to separate Summary and discussion. It is because certain core ideas of this study only appear in this section (and in the abstract), which should have been discussed in earlier sections. E.g. the notion of cold trains and warm trains only appears in the abstract and in Section 4. The authors should introduce such notion in the introduction to increase readability. Furthermore, the dynamical framework of “cold train” is one of the core results of this study. This alone deserves its own section.
Concerning the terms 'cold' and 'warm' trains, we shall entitle the previously analyzed train as 'warm trains' toward the end of the introduction, and refer the reader to the 'cold train', which is the outcome of our analysis.
In the revised version, a new separate section, #4, entitled "Dynamical considerations" will contain the description of the train, as appear in the beginning of the present Sec. 4, together with the two paragraphs dealing with the dynamics, Fig. 6 and the content of the appendix (as you asked us to do in your last comment). The rest of present section 4 will be entitled: "5. Summary and discussion".
- [related to introduction] In the introduction, the authors should explicitly indicate the existing “warm train” model could not explain the “train” observed over EM. Then this section would make more sense.
This point is addressed in our response to your previous comment.
Lines 231-236: I am a bit confused. At the beginning of the paragraph, it seems that “friction exerted by the sea surface” is not a contributing factor but at the end it appears to suggest that it is?
The relevant phrase from the paper presents the problematics of friction over sea surface as follow: "The friction exerted by the sea surface seems questionable. Indeed, during calm conditions smooth sea surface produce negligible friction. But, under the influence of a CL, with its induced winds, waves are created, which may enhance friction". It stresses that under stormy weather, such as associated by CLs, the rough sea exerts considerable friction. This statement relies on data of sea state during the cases analyzed (see line 234).
Figure 6: What level(s) of pressure, wind, etc are shown in the figure?
This figure represents the lower-levels. The isobars relate to the sea level pressure and the wind field describe the lower 1 Km. For the sake of clarity, we shall replace the phrase "Scheme of the train associated…" in the caption to "Schematic description of the lower-level configuration of the train associated..". The phrase "the maximum wind" will be extended to "the maximum wind within the lower 1 Km".
Lines 269-274: Could this research be applied to improve nowcasting/short-range forecast?
We identified type of regions that are prone to continuous heavy rains through the wind field. The precision of the regional models in mapping the meso-scale structure of the wind field enable to point at the left side of maximum wind bands south of CLs as potential regions for floods. We shall add this notion to the end of the summary.
Appendix A: This section is not mentioned in the main text. Since it is related to the train formation, perhaps the authors should consider including this section in the main text rather than in the appendix.
We accept your idea, and shall include the content of the appendix in the new section 4, dealing with dynamics as mentioned above.
Citation: https://doi.org/10.5194/nhess-2023-215-AC2