Preprints
https://doi.org/10.5194/egusphere-2023-478
https://doi.org/10.5194/egusphere-2023-478
04 Apr 2023
 | 04 Apr 2023

Distinct secondary ice production processes observed in radar Doppler spectra: insights from a case study

Anne-Claire Billault-Roux, Paraskevi Georgakaki, Josué Gehring, Louis Jaffeux, Alfons Schwarzenboeck, Pierre Coutris, Athanasios Nenes, and Alexis Berne

Abstract. Secondary ice production (SIP) has an essential role in cloud and precipitation microphysics. In recent years, substantial insights were gained into SIP by combining experimental, modeling, and observational approaches. Remote sensing instruments, and among them meteorological radars, offer the possibility to study clouds and precipitation in extended areas over long time periods, and are highly valuable to understand the spatio-temporal structure of microphysical processes. Multi-modal Doppler spectra measured by vertically-pointing radars reveal the coexistence, within a radar resolution volume, of hydrometeor populations with distinct properties; as such, they can provide decisive insight into precipitation microphysics. This paper leverages polarimetric radar Doppler spectra as a tool to study the microphysical processes that took place during a snowfall event on 27 January 2021, in the Swiss Jura Mountains, during the ICE GENESIS campaign. A multi-layered cloud system was present, with ice particles sedimenting through a supercooled liquid water (SLW) layer in a seeder-feeder configuration. Building on a Doppler peak detection algorithm, we implement a peak labeling procedure to identify the particle type(s) that may be present within a radar resolution volume. With this approach, we can visualize spatio-temporal features in the radar time series that point to the occurrence of distinct mechanisms at different stages of the event. By focusing on three 30-minute phases of the case study, and by using the detailed information contained in the Doppler spectra, together with dual-frequency radar measurements, aircraft in-situ images, and simulated profiles of atmospheric variables, we narrow down the possible processes which can be responsible for the observed signatures. Depending on the availability of SLW and the droplet sizes, on the temperature range, and on the interaction between the liquid and ice particles, various SIP processes are identified as plausible, with distinct fingerprints in the radar Doppler spectra. A simple modeling approach suggests that the ice crystal number concentrations likely exceed typical concentrations of ice nucleating particles by one to four orders of magnitude. While a robust proof of occurrence of a given SIP mechanism cannot be easily established, the multi-sensor data provides various independent elements each supporting the proposed interpretations.

Journal article(s) based on this preprint

14 Sep 2023
Distinct secondary ice production processes observed in radar Doppler spectra: insights from a case study
Anne-Claire Billault-Roux, Paraskevi Georgakaki, Josué Gehring, Louis Jaffeux, Alfons Schwarzenboeck, Pierre Coutris, Athanasios Nenes, and Alexis Berne
Atmos. Chem. Phys., 23, 10207–10234, https://doi.org/10.5194/acp-23-10207-2023,https://doi.org/10.5194/acp-23-10207-2023, 2023
Short summary

Anne-Claire Billault-Roux et al.

Interactive discussion

Status: closed

Comment types: AC – author | RC – referee | CC – community | EC – editor | CEC – chief editor | : Report abuse
  • RC1: 'Comment on egusphere-2023-478', Anonymous Referee #1, 16 May 2023
    • AC1: 'Reply on RC1', Anne-Claire Billault–Roux, 28 Jun 2023
  • RC2: 'Comment on egusphere-2023-478', Anonymous Referee #2, 17 May 2023
    • AC2: 'Reply on RC2', Anne-Claire Billault–Roux, 28 Jun 2023

Interactive discussion

Status: closed

Comment types: AC – author | RC – referee | CC – community | EC – editor | CEC – chief editor | : Report abuse
  • RC1: 'Comment on egusphere-2023-478', Anonymous Referee #1, 16 May 2023
    • AC1: 'Reply on RC1', Anne-Claire Billault–Roux, 28 Jun 2023
  • RC2: 'Comment on egusphere-2023-478', Anonymous Referee #2, 17 May 2023
    • AC2: 'Reply on RC2', Anne-Claire Billault–Roux, 28 Jun 2023

Peer review completion

AR: Author's response | RR: Referee report | ED: Editor decision | EF: Editorial file upload
AR by Anne-Claire Billault–Roux on behalf of the Authors (28 Jun 2023)  Author's response   Author's tracked changes   Manuscript 
ED: Publish as is (31 Jul 2023) by Timothy Garrett
AR by Anne-Claire Billault–Roux on behalf of the Authors (03 Aug 2023)  Author's response   Manuscript 

Journal article(s) based on this preprint

14 Sep 2023
Distinct secondary ice production processes observed in radar Doppler spectra: insights from a case study
Anne-Claire Billault-Roux, Paraskevi Georgakaki, Josué Gehring, Louis Jaffeux, Alfons Schwarzenboeck, Pierre Coutris, Athanasios Nenes, and Alexis Berne
Atmos. Chem. Phys., 23, 10207–10234, https://doi.org/10.5194/acp-23-10207-2023,https://doi.org/10.5194/acp-23-10207-2023, 2023
Short summary

Anne-Claire Billault-Roux et al.

Anne-Claire Billault-Roux et al.

Viewed

Total article views: 600 (including HTML, PDF, and XML)
HTML PDF XML Total Supplement BibTeX EndNote
372 209 19 600 30 7 9
  • HTML: 372
  • PDF: 209
  • XML: 19
  • Total: 600
  • Supplement: 30
  • BibTeX: 7
  • EndNote: 9
Views and downloads (calculated since 04 Apr 2023)
Cumulative views and downloads (calculated since 04 Apr 2023)

Viewed (geographical distribution)

Total article views: 583 (including HTML, PDF, and XML) Thereof 583 with geography defined and 0 with unknown origin.
Country # Views %
  • 1
1
 
 
 
 
Latest update: 14 Sep 2023
Download

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

Short summary
Secondary ice production plays a key role in clouds and precipitation. In this study, we analyze radar measurements from a snowfall event in the Jura mountains. Complex signatures are observed, which reveal that ice crystals were formed through various processes. An analysis of multi-sensor data suggests that distinct ice multiplication processes were taking place. Both the methods used and the insights gained through this case study contribute to a better understanding of snowfall microphysics.