Articles | Volume 18, issue 19
https://doi.org/10.5194/amt-18-5071-2025
© Author(s) 2025. This work is distributed under
the Creative Commons Attribution 4.0 License.Improved hydrometeor detection near the Earth's surface by a conically scanning spaceborne W-band radar
Download
- Final revised paper (published on 02 Oct 2025)
- Preprint (discussion started on 11 Feb 2025)
Interactive discussion
Status: closed
Comment types: AC – author | RC – referee | CC – community | EC – editor | CEC – chief editor
| : Report abuse
-
RC1: 'Comment on egusphere-2025-416', Anonymous Referee #1, 31 Mar 2025
- AC1: 'Reply on RC1', Marco Coppola, 07 May 2025
-
RC2: 'Comment on egusphere-2025-416', Anonymous Referee #2, 09 Apr 2025
- AC2: 'Reply on RC2', Marco Coppola, 07 May 2025
Peer review completion
AR: Author's response | RR: Referee report | ED: Editor decision | EF: Editorial file upload
AR by Marco Coppola on behalf of the Authors (03 Jun 2025)
Author's response
Author's tracked changes
Manuscript
ED: Referee Nomination & Report Request started (06 Jun 2025) by Leonie von Terzi
RR by Anonymous Referee #1 (19 Jun 2025)

RR by Anonymous Referee #2 (22 Jun 2025)

ED: Publish subject to minor revisions (review by editor) (23 Jun 2025) by Leonie von Terzi

AR by Marco Coppola on behalf of the Authors (16 Jul 2025)
Author's response
Author's tracked changes
Manuscript
ED: Publish as is (17 Jul 2025) by Leonie von Terzi
AR by Marco Coppola on behalf of the Authors (17 Jul 2025)
The submitted manuscript addresses the use of a conically-scanned radar for spaceborne measurements of precipitation. The concept underlies a radar instrument called WIVERN that may be developed and launched over the next decade, so continued analysis of the WIVERN instrument seems quite relevant to this publication’s readers. Previous publications on the topic of WIVERN include an overview of the design (2018), and various related aspects, including a radar simulator, effects of clutter in orography, impacts of channel cross-talk, effects of mispointing, and radar signal processing. The manuscript under consideration addresses clutter but appears to be covering new territory, relative to previous publications. It introduces the clutter problem and provides several related equations. It then shows two case studies of precipitation with clutter effects for CloudSat, EarthCARE, and for WIVERN. The discussion is generally clear and gives a balanced treatment of WIVERN’s capabilities as compared with nadir-looking spaceborne radars. I think it can be a valuable addition to the literature, but I do have some questions and comments that should be addressed.
Questions and Comments for the Authors:
- There are a number of other WIVERN publications that are not cited. It would be good to confirm that all clutter-related papers are referenced and that this paper explains its novelty relative to those.
- Around line 50, the advantages of conically-scanned W-band radar are noted, but it might be reasonable to list some disadvantages, in particular the large attenuation that needs to be removed when viewing liquid precipitation.
- I think the equations developed in Section 2.1 need better motivation, especially the use of the Gaussian antenna. It appears that the WIVERN calculations use a calculated pattern. Is the Gaussian used for CloudSat and EarthCARE? Is (7) the clutter reflectivity being plotted in Figure 2?
- Do the results in Figure 2 represent the total clutter, from all pulses that could arrive simultaneous with the atmospheric pulse, or only from the pulse illuminating the atmosphere? If only the latter, I would be concerned that the clutter estimate is not complete.
- Around line 125, it could be pointed out that even at the 14 m/s windspeed, the clutter appears small enough that it would be below the thermal noise for WIVERN.
- Line 193, the text could mention the land/ocean contrast that can be seen in Figure 7.
- Line 206: The text points out a thicker clutter signal when flying over land. This is related to the total clutter level and its profile, as well as the color table being used for the image. It might be clearer to mention the level and the 3-dB width.
- Figure 8 compares the simulated WIVERN and CloudSat data. What are the vertical resolutions (not slant range) in the two cases?
- The smaller figure format used for the Labrador case might also work for the west coast case. The larger figures for that case are easier to read but also require a lot of moving around to see both text and figures, when reading.
- I think the text for the snowfall case could be expanded to give more explanation for what is seen. Is the main difference (better detection down to the ground for snowfall) related to the lack of strong attenuation?
- The statistical analysis in 3.2 could also provide a better explanation. In particular, line 247 notes that the “results clearly highlight”. It would be good to point out the particular results in detail, explaining the choice of the definition of DeltaZ and explaining the significance of the plots. This explanation would also help with understanding of the results in Section 3.3. What was the reason for using the SCR=5 dB height?
- Line 255 – in what sense is the WIVERN sampling improved? Is this related to the wide swath, which is, indeed, a nice feature?
Minor edits:
- Line 27, the parentheses make reading the sentence difficult. Please consider revising.
- Consider removing paragraph breaks at lines 32, 45, 57, 117, 308.
- Figure 1, please add the angles used in Section 2.1.