the Creative Commons Attribution 4.0 License.
the Creative Commons Attribution 4.0 License.
| 01 Jun 2026
Contribution of the solar wind-magnetosphere-ionosphere-atmosphere coupling to rapid intensification of tropical cyclones and transition of Mediterranean subtropical cyclones to tropical-like cyclones
Abstract. We investigate rapid intensification of tropical cyclones and transition of Mediterranean subtropical cyclones to tropical-like cyclones in the context of solar wind-magnetosphere-ionosphere-atmosphere coupling. Using the superposed epoch analysis of time series of solar wind variables, it is observed that rapid intensification of tropical cyclones and transition of Mediterranean subtropical cyclones to tropical-like cyclones tend to occur following arrivals of high-speed solar wind streams from coronal holes or impacts of interplanetary coronal mass ejections. Aurorally generated atmospheric gravity waves can influence the development of weather. While these gravity waves reach the troposphere with attenuated amplitudes, they can contribute to the release of conditional symmetric instability leading to latent heat release and intensification of extratropical and tropical cyclones. We use the meteorological re-analysis to evaluate slantwise convective available potential energy to assess likelihood of conditional symmetric instability that can be released by over-reflecting aurorally generated gravity waves leading to slantwise convection and intensification of storms.
- Preprint
(3923 KB) - Metadata XML
-
Supplement
(3935 KB) - BibTeX
- EndNote
Status: final response (author comments only)
-
CC1: 'Comment on egusphere-2026-2327', Vanina Lanabere, 01 Jun 2026
-
AC1: 'Reply on CC1', Paul Prikryl, 22 Jun 2026
The comment was uploaded in the form of a supplement: https://egusphere.copernicus.org/preprints/2026/egusphere-2026-2327/egusphere-2026-2327-AC1-supplement.pdf
-
AC1: 'Reply on CC1', Paul Prikryl, 22 Jun 2026
-
RC1: 'Comment on egusphere-2026-2327', Anonymous Referee #1, 05 Jul 2026
The comment was uploaded in the form of a supplement: https://egusphere.copernicus.org/preprints/2026/egusphere-2026-2327/egusphere-2026-2327-RC1-supplement.pdf
-
AC2: 'Reply on RC1', Paul Prikryl, 21 Jul 2026
The comment was uploaded in the form of a supplement: https://egusphere.copernicus.org/preprints/2026/egusphere-2026-2327/egusphere-2026-2327-AC2-supplement.pdf
-
AC2: 'Reply on RC1', Paul Prikryl, 21 Jul 2026
-
RC2: 'Comment on egusphere-2026-2327', Anonymous Referee #2, 17 Jul 2026
The authors are proposing that the solar wind (in particular high speed streams and coronal interaction regions) may trigger atmospheric instabilities via aurorally-driven atmospheric gravity-waves and this may lead to an intensification of tropospheric storms (hurricanes and medicanes).
The proposed link is based on an older paper of the authors and sounds reasonable. It has already been applied to different tropospheric weather phonomena as intensively noted in the introduction. Regarding the solar wind forcing of hurricanes some multi-epoch analysis of the presented paper show an interesting coincidence (e.g. the increased CIR numbers preceeding the strom intensification in Fig. 6) as well as an increasing solar wind velocity for the intensification in all presented multi-epoch analysis - which was impressive for me.However there are major significant points of criticism that need to be solved before considering publication. Applying the proposed method the authors are presenting that 42% of the hurricanes are following CIRs. To me this seems similar than for a random distribution with the same data processing. Also the temporal dimension of the forcing link is very vague. The proposed three day time window is too large to draw direct conclusions. And finally I am not happy with showing single events for an effect that should appear on a statistical basis only.
The authors want to link all tropospheric weather phenomena with space weather by temporal coincidence, which is difficult due to the 3 day time window. My suggestion would be to investigate the energy density of aurorally driven waves in the troposphere in contrast to other disturbances. While any disturbance may trigger an instability, the probability of this triggering should increase with the energy of the disturbance. In case of Fig. 4 where the authors link all hurricane intensifications to solar forcing even though there already is a lot of mass in motion, horizontally as well as vertically - this clear link to solar forcing is only reasonable if AGW energy density is dominant.
Major:
1.) is the probability increased?
24% of the hurricanes with a strong wind speed increase happen after a HSS/CIR with solar wind speed >500km/s (line 125)
18% happen after HSS/CIR in the range of 300-500km/s (line 140).
I hope I got that right, so in total we have a probability of 42% that a hurricane happens after a (>300km/s) HSS/CIR.
Is that special? Let's use Fig.4 and count the CIRs. There are 16 CIRs in 3 months. That makes 4 CIRs per month, roughly of course. According to Figures 2/3 you are counting a hurricane as "belonging" to a CIR if it intensifies during the next three days. That on average makes about 12 days a month when a storm intensification would be counted as belonging to a CIR - regardless of any causal reason. With 12 days a month, even a completely random distribution of storm intensifications should show a co-incidence of about 40%. Well, give a take a few percent for my very poor statistic on CIRs but if this correlation does show anything than that it is ramdom.
belongs also to:
-l. 144 "often"
-l. 215 in case that these results were derived with the same method I would be careful with this statement as well
2.) Temporal dimension of the depencency:
How long does it take from a CIR forcing until we may expect the highest wind velocity increase? According to the paper it reaches from almost immediatelly until 3 days later. That is a very long time span if you want to see a direct impact on an instability that also might be the result of other disturbances. In Fig. 1 solar forcing and highest wind velocity increase seem to happen simultaneous. In that case we would not need a trigger. The forcing should happen before the strong wind increase takes place - and during that time (e.g. day -1) the solar wind forcing is very low (minimum in solar wind velocity in all plots of Fig. 1).
However, there seems to be a maximum in solar wind density at day -1. This even with the low solar wind speed this has an impact on the solar wind dynamic pressure and might be connected with increased substorm activity. Comparing that with AL or SML index might tell more.
belongs also to:
-l. 109 "following"3.) Single storm studies:
The paper shows a couple of single storms (e.g. Section 4) that may be driven by solar wind forcing. We probably agree that triggering an instability is a statistical effect and might have different reasons. Without having any information on the disturbance that may (or may not) trigger this (may be existing) instability I do not see a benefit in single event studies.
4.) Fig.4 shows the problem of high rate of solar wind forcing in combination with the wide atmospheric response-time window.
Yes, you may attribute many of the storm intensifications with solar drivers. However, the same way you may also temporally connect almost any ending of the hurricanes with a CIR. The arbitrary response time window is too long to draw conclusions out of single storms.
And it should be very unlikely if every storm intensification in Fig. 4 (3 times three consecutive ones) would be linked to solar wind forcing (energy density argument, see above).
5.) introduction in general: I believe that the authors are convinced by the space weather forcing on tropospheric instabilities but an introduction should give an overview to the field and that also needs to include critical aspects, as the limited energy of an AGW compared to other waves, ongoing debate on the validity. I am sure the authors have these citations at hand.
minor:
-The title is very long.
-l. 22 The first two sentences if the introduction contain 11 self-citations in a row without mentioning other work. Does that mean the authors are working alone on this field or they do not want to present a comprehensive overview as desired in an introduction?
-l. 29 "Low-level winds...are favorable conditions for over-reflection..." this statement needs to be explained or cited.
-l. 38 "Because of Joule heating and Lorentz forcing ... a key component of... coupling... is the generation of... waves..." Please rephrase this sentence. And what is meant by Lorentz forces in this context? Do you mean Joule heating by Pedersen currents?
-l. 55 (all) links need to be referenced with the last access date
-l. 55 "best tracks" what is the criteria for a best track?
-l. 60 What does this 24h limitation mean? The 6h timesteps are averaged? running average? The 6h values are used to calculate the maximum intensity but that's not very accurate?
-l. 71 The list is a black box at the moment. Please provide it (maybe as supplement) and note if all existing data has been used or any selection has been made. Please also include the derived intensification time. As such everyone may check the data and verify the findings.
-l. 85 "updated" what has been updated and by whom?
-Fig. 1: All lines should use the available y-axis space.
-Fig. 1: (l. 223) SLP is not explained in the text. Is it Mean Storm Low as indicated in the Figure or Sea Level Pressure?
-l. 117: "that were associated with intensifying hurricanes" please clarify what is meant by this criterium
-Fig. 2: The discussion of the upper panel is missing. In case that this panel adds information to the paper, please discuss it, otherwise it should be removed.
-Fig. 2 How many of the 87 and 363 storms have a slantwise instability that is the precondition for a triggered release?
-the paper mentions geomagnetic storm several times even though the DST threshold for a strom is not met. The smallest geomagnetic strom ("moderate") starts at -50nT (e.g. l. 193)
-l. 156 Oho intensified already before the CIR
-Fig. 4 is hard to read: tiny text, faint colors, and the legend "*20 nT" should be "*20/nT" as the y-axis is dimensionless. Maybe "*20 in nT" or even a second axis would be better.
-Fig. 5 needs a colorbar and a more detailed description
-l. 189 I do not see any intensification after the CIR on 14-15th of Sept.
-l. 195 not sure if there even is a CIR
-l. 240 This statement seems to be wrong. Fig. 8 shows 1, 6 and 5 CIRs on the days preceeding the WAA events. That is not outstanding to the other days.
-Fig.7b: colorbar is missing. And it did not find any discussion of that figure.
-l. 268 "that were associated with medicane storms" (same in caption of Fig. 14) that needs to be clearly defined
-l. 373 "mostly because of data gaps" makes this a vulnerable point of the multi-epoch analysis. Please provide more information.
-Fig. 15: colorbar, and again, I do not see any use in showing single storm examples. They all show that a couple of days defore a CIR happened, which statistically is the case every 7.5 days - so what should this tell us?
-l. 411 Is Prikryl (2024) the correct citation for ERA5 reanalysis? Shouldn't that be Hersbach?typo/grammar/style:
-l. 16 "development of weather" systems/patterns?
-l. 32/39 no need to introduce the acronym MIA as it is just only once again - together with the full form
-l. 70 The link is probably too long (remove #...)
-l. 74 ...indices...are diagnosed... . Please rephrase.
-l. 90 Ångström (first letter)
-l. 95 SPE in space weather is strongly connected to "solar proton event". Please use another abbreviation, maybe SPEP.
-Fig. 15 caption: if MSLP is minimum sea level pressure, what might be a minimim MSLP?
-l. 125 "underwent" -> with? (as precondition for the selection) followed arrivals
-l. 202 TC not introduced
-l. 224 (and Figures) RI=20+ typically is written $RI \ge 20$ and is the unit correct? kt or kt/24h?
-l. 393 this indeed is a moderate geomagnetic stormCitation: https://doi.org/10.5194/egusphere-2026-2327-RC2 -
AC3: 'Reply on RC2', Paul Prikryl, 21 Jul 2026
The comment was uploaded in the form of a supplement: https://egusphere.copernicus.org/preprints/2026/egusphere-2026-2327/egusphere-2026-2327-AC3-supplement.pdf
-
AC3: 'Reply on RC2', Paul Prikryl, 21 Jul 2026
Viewed
| HTML | XML | Total | Supplement | BibTeX | EndNote | |
|---|---|---|---|---|---|---|
| 137 | 45 | 15 | 197 | 22 | 8 | 4 |
- HTML: 137
- PDF: 45
- XML: 15
- Total: 197
- Supplement: 22
- BibTeX: 8
- EndNote: 4
Viewed (geographical distribution)
| Country | # | Views | % |
|---|
| Total: | 0 |
| HTML: | 0 |
| PDF: | 0 |
| XML: | 0 |
- 1
Main comment:
The analysis and conclusions in Fig. 2 is methodologically circular.
"Fig. 2 shows SPE analysis of green corona intensity (top panels) and solar wind variables (middle panels) keyed to arrivals of HSS/CIRs that were followed within 3 days by hurricane RI ≥ 30 kt/24h" (L117-119).
As a result, the figure cannot demonstrate that “RI of hurricanes often occur following arrivals of HSSs from coronal holes or impact of ICMEs” (L144-145), it only reflects the pre‑selection criterion. To support the stated conclusion, the analysis must for example include all HSS/CIR arrivals (with and without RI) and all RI events (with and without preceding solar‑wind activity.
The SPE analysis in Fig. 14a suffers from the same circular‑selection problem noted earlier. By compositing only those HSS/CIR arrivals that were already known to be associated with medicanes, the analysis cannot demonstrate that “most medicanes developed following HSS/CIR arrivals.” This conclusion is built into the event selection itself. L368-370
General comments:
- I would recommend the authors to provide some general statistics of the 363 hurricane events. How many events of the list exceed the maximum rapid intensification (RI > 30 kt/24h)?. How many occurred within n days from the ICME, HSS arrival?
- Provide information of number of medicine events.
- The Richardson and Cane (2010) catalog provide a consistent identification of ICME. What about the HSS/CIR? What is the catalog or criteria used to identify such structure in the solar wind data?
- Superposed epoch analysis of solar wind conditions should not only indicate the mean values. It also needs a measure of variability (e.g., quartiles, standard deviation). Without showing the spread, it is impossible to assess the statistical significance or robustness of the composited time serie.
- Provide information about the extended list of tropical cyclones with convective bursts.