General Comments

This manuscript describes the atmospheric and oceanic measurements taken during the 40-day ship cruise of FS Meteor in the moist tropical Atlantic as part of the BOWTIE campaign in August and September 2024. After providing a brief introduction into the historic context of the measurements and their coordination within the larger-scale ORCESTRA campaign, large parts of the manuscript are dedicated to the description of the comprehensive suite of in-situ and remote-sensing instruments measuring atmospheric and oceanic variables (section 3). The authors also present instrument comparison analyses for different measured parameters (section 4) and close with two case studies of atmospheric phenomena within the main focus of the project (section 5). All observational data described in the manuscript are well documented and publicly available via a dedicated data browser for the ORCESTRA campaign using a modern IPFS infrastructure, which eases the access to and usability of the data.

Overall, the manuscript describes a unique and comprehensive data set that can be of great relevance for both the meteorology and oceanography community. Given the large number of deployed instruments and studied processes, the rather technical and lengthy description in section 3 is justified and will be referenced by future data users. My main criticism concerns the following sections 4 and 5, where the authors should better motivate the presented analyses and provide more scientific context. I acknowledge the fact that this data description paper does not aim for deep scientific analyses, however, I believe that the authors could do a better a job in characterizing the uniqueness of their data set. The instrument comparison of sampled rainfall in section 4 is certainly of help when interpreting the data, but it is unclear if these results are specific to the BOWTIE deployment and observation period/region or if the same results could have been found with existing data of these suite of instruments. Also the choice of case studies in section 5 appears arbitrary and the reader is left on their own to judge the significance of these events and what new aspects the data set could add to our current knowledge of process understanding. Nevertheless, my overall assessment of this study is positive and after addressing these general concerns as well as the specific comments listed below, I would be happy to recommend the manuscript for publication in ESSD. 

Specific Comments

1. L34: Please define "small-scale". Does this scale differ between atmosphere and ocean?
2. L41-42: "It is in this context that the measurements of BOWTIE are important.": Please rephrase to be more specific here.
3. L164-180: This should be a table.
4. L181-186: I suggest to remove or shorten this paragraph as it does not appear to be relevant for the average data user.
5. L229: Define "lower" elevation angle
6. L266-270: I am skeptical if this level of detail is needed here.
7. L312-313: Specify what "perpendicular" means. I would guess that it refers to the orientation of the optical sampling paths. Why would you expect the measurements to depend on the orientation of the instrument?
8. L345: What does "scrutiny is advised" mean? Please specify or remove.
9. L479: What is the P2 process study region? Please define or remove.
10. L564: I guess you are implicitly saying that the irregular measurement potentially leads to biased sampling. If so, please state this explicitly.
11. L568: This explanation is unclear to me.
12. L575:  ... to be constant *with IWV*  -> Calling this a bias could be maybe more precise.
13. L577-578: See previous comment.
14. L584: exact quantification of *the occurrence and amount of* surface rain
15. L586: Why can "one expect that the detection of rain is more likely to be similar among the instruments"? Given the different sampling methods and volumes, I would not agree with this statement.
16. L622-624: Same as earlier comment: Why would you expect differences in the rain detection due to the alignment of sensors? Given the last statement, I would rather suspect the sensor sensitivities (or other technical issues) than their alignment causing the differences.
17. L638-640: Is this result specific to the BOWTIE deployment or instruments? Would you expect different results, if the same suite of instruments would be set up somewhere else?
18. L714-715: Can you speculate on possible explanations? Has this been observed before? Is this specific to the measurement location or the sensor types?
19. L732-733: "should be taken with caution": What does this mean? Can you give more specific guidance for the data user?
20. L738-749: This paragraph requires much more context, e.g.: What is the significance of doldrums? How many events have been observed during the cruise? Was this a event special in any sense? Are there any new aspects of doldrums that cannot be studied with existing observations? Is the observed vertical structure consistent with expectations?
21. L751-767: Same as for the previous paragraph: Please add more context on the significance of this case study. Since such convective gust fronts have been extensively observed and studied before (also over the tropical Atlantic), it would be important to clarify, which new aspects this data set can add to the literature.
22. L798: "this does not depend on the velocity of the ship": To my understanding, this was not stated before (or only implicitly)
23. L799: same as previous comment
24. L803-804: Same as earlier comments. Please try to give move specific guidance to the data user.
25. L808: "which is a first step for a deeper understanding": I find this statement way too broad and unspecific.

Technical Corrections

1. L7: Please use consistent notation for "2-D" vs "3D" (see L11 and elsewhere)
2. L10, 43: upper ocean (without hyphen)
3. L28: Define ocean Conductivity-Temperature-Depth-Oxygen (measurements?)
4. L45: Please define "doldrums" when first used
5. L52: I suggest to remove the repetition "a 40-day journey of FS Meteor" here
6. L83: PIRATA
7. L83-84: Please use a consistent notation for coordinates ("8°N, 38°W" vs "8°N and 38°W")
8. L96: for atmospheric measurements
9. Fig. 3, Caption: Please explain the meaning of the grey periods in panel a)
10. L100: CTDO stations (without hyphen)
11. L114: Please define the acronyms "PICCOLO" and "STRINQS"
12. L116: Please define "drones" already on first use
13. L117: lowest 1.5 km
14. L123: EarthCARE
15. L140-141: I suggest to merge these two sentence to avoid repetition.
16. L150-153: Tables 2 and 3 are not referenced.
17. L161: I suggest to make it a sub-sub-section (3.1.1 and following)
18. L165: resolution of ... *for wind direction and wind speed*, respectively
19. L187: Who is Prof. Hasse?
20. L208: in Mindelo *before departure*
21. L215: in off-wavelengths (?)
22. L232: 90° elevation angle
23. L253: Is this the same stabilisation platform already mentioned in L239-240? If so, I suggest to move the previous sentence here.
24. L293: I suggest to move any support statements to the acknowledgments.
25. L310 (and elsewhere): Please move full links to a footnote (as done earlier in the manuscript) or to the literature section
26. L321: The term "wind lidar" is rather general, given that the following paragraph also describes a wind lidar. I suggest a more specific paragraph heading.
27. L398: "another foot or so": Please avoid slang and non-metric units.
28. L402: recording averages with 1-s resolution/every second
29. L403: sidetracked -> impacted/biased (or similar)
30. L442-444: Use lower case
31. L518: Define "HF"
32. L519: Define "LOV"
33. L535: latest *access* (?)
34. L536: from the ECMWF-IFS model
35. L551: I suggest to make it sub-section 4.1
36. L561: decrease *of* 0.37 kg/m2
37. L571: Please be more specific than "interestingly"
38. L571: IWV is "higher", not "moister"
39. L573: trustworthy -> reliable/accurate
40. L577+579: gap -> difference
41. L591: There is no Section 3.1.2.
42. L603: detected by a different number of instruments
43. L662-668: Remove (redundant information that belongs to the figure caption)
44. L671-674: Move to the figure caption.
45. L677: between the ocean surface and the lower atmosphere
46. L689: section 3.2.3
47. L691-693: Move to the figure caption.
48. L704: Please use K for temperature differences (here and elsewhere in text and figures)
49. L710: Delete "during the night" (repetition)
50. L711: is *observed for* 4.7 % of ...
51. L726-727: can be -> is
52. L727: Delete "during the day" (repetition)
53. L728: Only one *measurement*
54. L730: delete "in general"
55. Fig. 10a: Please decrease the widths of the blue and grey lines to increase readability.
56. Fig. 10, caption: Remove "y axis" and "x axis"
57. Fig. 10, caption: Similar to -> same as
58. Figs. 11 and 12, caption: Doldrums event on August 26, 2024: ...
59. L769: Ozean
60. L770: moist (?) tropical Atlantic
61. L781: FS Meteor (lower case)
62. L791: by *up to/on average* (?) 2 kg/m2
63. Data set/DOI table: What is RAPSODI?

< General comments >

This article provides basic information about observations made during the BOWTIE cruise that would act as a reference for future use. The authors also demonstrate the characteristics of ocean and atmosphere during the two cases; calm conditions and convectively active conditions as indications for future studies. The authors’ efforts producing quality-controlled data and providing those data to the broader community would be highly appreciated. However, several descriptions are unclear. In addition, while I understand this is an introduction paper of BOWTIE datasets, some “depths” are needed to ensure their data reliability. I put some questions and suggestions as specific comments below. Please revise them accordingly.

< Specific comments >

1) L. 67-69; It is helpful to know the locations of two ports, so that the readers can obtain UTC from their local times and also can find rough distance between them. (I know we can see it in Fig. 2, but it is better to describe it in the text.)

2) L. 97; It might be better to add “aerial” before “drone”, as recently uncrewed ocean surface vehicles such as saildrone and wave-glider are also referred as marine (oceanic) drones.

3) L. 111-143; It is one idea that section 2.3 can be summarized into one table, which lists the simultaneous observations among ORCESTRA’s sub-campaigns instead of the current description style. I mean, it is not necessary to divide into two sub-sections. Instead, one section with one table might be enough. Or, a paragraph that explains the following two sub-sections can be inserted at the beginning of this section.

4) L. 114; If there is no published work on STRINQS, at least, relevant paper (Stevens et al. 2026 Tellus paper) should be cited, as the authors did for PERCUSION and CELLO in the next subsection. In addition, the readers cannot imagine anything from its abbreviation alone. Please spell them out.

5) L. 131; These numbers (17 overpass and 7 additional ...) might be the ones only during the period corresponding to the BOWTIE campaign. I found the different numbers (23 flights during Aug. 11 - Sept. 28) in Table 1 of Stevens et al. (2026, Tellus). If so, it is better to describe such facts to avoid any misleading on PERCUSION and/or HALO campaign period.

6) L. 156-205; Was any calibration for each sensor performed before/after the cruise? Such calibration is useful to detect temporal drifts. If only annual maintenance by the instrument manufacturers is done, it should be noted. In any case, please provide calibration information (not calibration results).

7) L. 206-530; It is better to provide the same basic information for all instruments with notification (name, manufacturer, type, sampling intervals, etc.) first. It is hard to understand the current descriptions which is which. Or, simply refer to Tables 2 and 3, which tell above. In addition, it is possible to omit descriptions on sensor types in the text, as we can see them in the tables.

8) L. 251-270; After all, final quality-controlled datasets of W-band radar have not been produced yet. Right? If so, it should be mentioned. Also, if any definitions of QC level (or version) exist, it should be noted for future updates.

9) L. 367-370; Any special reason to set the timing of reaching top of troposphere at the nominal 00/03/../21 UTC? As the authors may know, WMO requires to launch the baloon between 45-min to 15-min prior to the nominal time as much as possible. This makes it possible to re-launch in case of failure within the same nomintal time slot. (So, I guess re-launch was not performed during the BOWTIE as the same slot.) Also, I wonder if those data were sent to global communities through the GTS or not. If yes, it should be noted.

10) L. 375-376; I wonder if any quality check on near surface data was performed or not. As long as I read Schulz et al. (2024) package, which is cited here for postprocessing, I cannot find any explicit description on that. In the past big campaigns in the tropics such as TOGA-COARE in the western Pacific and DYNAMO in the Indian Ocean, special care was taken for radiosonde near-surface data obtained onboard especially in the calm sea conditions (e.g., Wang et al., 2002; Ciesielski et al., 2014), which might affect boundary layer research. If apparent errors are not found, it is fine. If check was not done, at least, it should be noted. Please note that in old days (like TOGA-COARE era) many errors were attributed to radiosonde itself or operation. However, I mention here that even accurate data were taken, data itself around the ship might be distorted due to the ship structure. For example, I’m afraid of any influence from a funnel and deck, if a schematic in Fig. 4a demonstrates actual operation. So, quality checks are required to confirm it.

References.

Ciesielski, P. E., H. Yu, R. H. Johnson, K. Yoneyama, M. Katsumata, C. N. Long, J. Wang, S. M. Loehrer, K. Young, S. F. Williams, W. Brown, J. Braun, T. Van Hove, 2014: Quality-controlled upper-air sounding dataset for DYNAMO/CINDY/AMIE: Development and corrections. J. Atmos. Oceanic Technol., 31, 741-764. https://doi.org/10.1175/JTECH-D-13-00165.1

Wang, J., H. L. Cole, D. J. Carlson, E. R. Miller, K. Beierle, A. Paukkunen, and T. K. Laine, 2002: Corrections of humidity measurement errors from the Vaisala RS80 Radiosonde-application to TOGA COARE data. J. Atmos. Oceanic Technol., 19, 981-1002.

https://doi.org/10.1175/1520-0426(2002)019%3C0981:COHMEF%3E2.0.CO;2

11) L. 391-396; Since ISAR cannot be operated under rain, this fact should be noted.

12) L. 399-402; I cannot understand this description, because usually a sea snake is deployed near the bow or far aside avoiding the ship’s wake. Fairall et al. (1997), which is cited here, also mentioned they deployed a sea snake from an outrigged boom about 4 m from the ship’s hull. Similar discussions can be found in many papers (e.g. de Szoeke, 2021). Could you confirm this point (sea snake was deployed within the influence of wake intentionally)?

Reference.

de Szoeke, S. P., 2021: Fast floating temperature sensor measures SST, not wet-bulb temperature.  J. Atmos. Oceanic Technol., 38, 995-1000. https://doi.org/10.1175/JTECH-D-20-0193.1

13) L. 493-500; It might be better to cite Pinkel et al. (2011) paper on Wire Walker explanation.

Reference.

Pinkel, R., M. A. Goldin, J. A. Smith, O. M. Sun, A. A. Aja, M. N. Bui, and T. Hughen, 2011: The Wirewalker: A vertically profiling instrument carrier powered by ocean waves. J. Atmos. Oceanic Technol., 28, 426–435. https://doi.org/10.1175/2010JTECHO805.1

14) L. 551-582; Integrated water vapor. It is not necessary to add any figures, but I’m wondering if the authors compared those data from diurnal cycle viewpoint. This is useful to confirm dry bias of radiosonde due to solar radiation. Besides, as asked in my previous comments on radiosonde measurement, previous studies indicated careful treatment on near-surface data was needed for ship-based data, which may cause drier/wetter in daytime/nighttime. So, I believe it is worth checking.

15) L. 607-637; In L. 271-279, the authors mentioned MRR had problems with deployment. Doesn’t it affect anything on detection technically?

16) L. 734-767; I cannot see the “philosophy” of these selections as examples. What kind of actions do the authors expect from the readers as a next step? Or, the authors simply demonstrate the usefulness of data? If the authors intend to provide the readers with guidance for future studies, it should be explicitly mentioned using these examples.

17) L. 748; “11 UTC” might be better to be expressed as local time.

< Technical corrections >

1) Fig. 2, caption; typo (pepth -> depth)

2) L. 147; STRIN”G”S --> STRIN”Q”S

3) L. 278-279 and L. 627; Which is correct, “> 3 dBz” or “greater than 3.1 dBz”?

4) L. 591; Not Section “3.1.2” but “3.2.1”?

5) L. 929; Exact citation is required. This paper is from “Reviews of Geophysics, 17, 1762-1772. https://doi.org/10.1029/RG017i007p01762”

6) L. 967; Published. https://doi.org/10.1175/BAMS-D-25-0166.1