Derivation of aerosol profiles for MC3E convection studies and use in simulations of the 20 May squall line case

Fridlind, Ann M.; Li, Xiaowen; Wu, Di; van Lier-Walqui, Marcus; Ackerman, Andrew S.; Tao, Wei-Kuo; McFarquhar, Greg M.; Wu, Wei; Dong, Xiquan; Wang, Jingyu; Ryzhkov, Alexander; Zhang, Pengfei; Poellot, Michael R.; Neumann, Andrea; Tomlinson, Jason M.

doi:https://doi.org/10.5194/acp-17-5947-2017

Articles | Volume 17, issue 9

https://doi.org/10.5194/acp-17-5947-2017

© Author(s) 2017. This work is distributed under
the Creative Commons Attribution 3.0 License.

https://doi.org/10.5194/acp-17-5947-2017

© Author(s) 2017. This work is distributed under
the Creative Commons Attribution 3.0 License.

Articles | Volume 17, issue 9

Research article

|

15 May 2017

Research article |

| 15 May 2017

Derivation of aerosol profiles for MC3E convection studies and use in simulations of the 20 May squall line case

Ann M. Fridlind, Xiaowen Li, Di Wu, Marcus van Lier-Walqui, Andrew S. Ackerman, Wei-Kuo Tao, Greg M. McFarquhar, Wei Wu, Xiquan Dong, Jingyu Wang, Alexander Ryzhkov, Pengfei Zhang, Michael R. Poellot, Andrea Neumann, and Jason M. Tomlinson

Download

Final revised paper (published on 15 May 2017)
Supplement to the final revised paper
Preprint (discussion started on 14 Nov 2016)
Supplement to the preprint

Interactive discussion

Status: closed

AC: Author comment | RC: Referee comment | SC: Short comment | EC: Editor comment

- Printer-friendly version

- Supplement

RC1: 'Review of Use of an observation-based aerosol profile in simulations of a mid-latitude squall line during MC3E: Similarity of stratiform ice microphysics to tropical conditions', Anonymous Referee #1, 01 Dec 2016
- AC1: 'Responses', Ann Fridlind, 16 Feb 2017
RC2: 'Review of “Use of an observation-based aerosol profile in simulations of a mid-latitude squall line during MC3E: Similarity of stratiform ice microphysics to tropical conditions” in ACPD by Fridlind et al.', Anonymous Referee #2, 27 Dec 2016
- AC2: 'Responses', Ann Fridlind, 16 Feb 2017

Peer-review completion

AR: Author's response | RR: Referee report | ED: Editor decision

AR by Ann Fridlind on behalf of the Authors (16 Feb 2017) Author's response Manuscript

ED: Referee Nomination & Report Request started (23 Feb 2017) by Corinna Hoose

RR by Anonymous Referee #1 (27 Feb 2017)

Suggestions for revision or reasons for rejection

Review 2 of Use of an observation-based aerosol profile in simulations of a mid-latitude squall line during MC3E: Similarity of stratiform ice microphysics to tropical conditions

Thank you for addressing my concerns. The manuscript is much improved, particularly organization and readability. It is ready for publication in my opinion. I make a few, minor suggestions below.

Specific comments / suggestions
Page 4, Lines 20-24 – The first sentence could be rewritten for clarity, e.g., “The large spread between CCN, HTDMA, and ground-based CPC measurements reflect the large variability in nucleation mode aerosol concentrations.” To me, it also makes more sense to place this paragraph along with the first to separate discussions of number concentration and hygroscopicity.

Page 6, Line 1 – I would include the “user-determined size” employed in this case for nucleation mode truncation.

Page 9, Line 29; Page 10, Line 5 – -10°C / -16°C are the mean temperatures at these altitudes? Please include T ̅ in the parentheses.

Page 11, Lines 5-6 – The Bigg 1953, Meyers et al. 1992, and Cooper 1986 schemes which are used for ice nucleation are known to have limitations since they do not account for spatiotemporal variation in INP, e.g. Prenni et al. BAMS 2007 or DeMott et al. PNAS 2011. This point could be made here in the note that “critical aspect of ice nucleation” may be missing.

Page 30, Figure 5 caption – Reword second sentence for clarity: “The campaign-wide median profiles at each elevation (red lines) are archived as Supplement 2.”

Page 31, Figure 6 – I still struggle to interpret all of the information in this figure. Given that the distributions in each mode are ultimately averaged in time, could these average number concentration, geometric mean dry diameter, and standard deviation values be presented? And the colored values from various Julian dates omitted or moved to Supplemental Information?

Page 36, Figure 11 right hand panels – Would it make comparison of the BASE simulation and observed number size distributions easier if the y scale were logarithmic?

Page 46, Table 2 caption – It would be helpful to indicate that the range in these values comes from the fact that they are calculated from “five level legs between 13.9 and 14.9 UTC” (otherwise, it seems as if there should be just two discrete values from the two methods).

Referee Report: PDF

Hide

RR by Anonymous Referee #2 (19 Mar 2017)

Suggestions for revision or reasons for rejection

Second Review of the ACP manuscript “Use of an observation-based aerosol profile in simulations of a mid-latitude squall line during MC3E: Similarity of stratiform ice microphysics to tropical conditions” by Fridlind et al.

The authors addressed the majority of my comments in the previous round. However, there are a few comments that need further work as detailed below,
(1) A table for the data listed on each panel in Figure 6: I noticed both reviewers of the paper suggested this but the authors did not follow the suggestion. Currently, with so many values on the panels (some data are even overlapped with the lines of the plots), it is simply too much and difficult to focus on anything. If the values are provided in the supplemental material, then refer to the supplemental material and remove from the panels. If not, then have a table listing them would be clearer (also make the plots neater).

(2) About my major comment #1, it seems that the authors’ response is not for this comment. By reading the revised manuscript, I still have the similar concerns. The title and introduction are not well aligned with the objectives and the content of this study and need further clarification. Basically the paper consisted of two parts: retrieved aerosol SD for MC3E cases and examine the stratiform ice microphysics from a single case study with and without the retrieve aerosol SD. The current introduction is mainly for the second part of the study and essentially no context/background for the first part (I only see one sentence related to it at line 27-29 on P2). For readers who are not in the aerosol-cloud interaction fields, they might not know the connections between aerosols and cloud properties. Therefore, context/background (such as the general relationships of aerosols with clouds and the significance of the aerosol impact could be) is needed for part 1. In part 2, since the authors show that the biases of stratiform ice microphysics is not depending on aerosol used, discussion about that the biases might not caused by aerosol impact (at least for the synoptic system simulated in this study) would be useful.
The current title is worded as “Similarity of stratiform ice microphysics to tropical conditions”, which makes readers anticipate the comparison results between the simulated case and a tropical case. However, no results are shown for this point, and this is only a discussion point in Section 5. Therefore, the title needs to be changed to better aligned with the results of the paper.

(3) About secondary nucleation in Morrison scheme (my comment #20), the scheme does have an option for separation of cloud base nucleation from secondary nucleation. The default option is for cloud base nucleation only (i.e., the supersaturation parameterized in ARG scheme nucleation is only for grid points without pre-existing cloud). To consider secondary nucleation, supersaturation calculation needs to be modified to consider the condensational growth of the existing droplets. Yang et al. (2015) has the details to add the secondary ice nucleation into Morrison scheme (Yang et al. 2015, Aerosol transport and wet scavenging in deep convective clouds: A case study and model evaluation using a multiple passive tracer analysis approach, J. Geophys. Res. Atmos., 120, doi:10.1002/2015JD023647).

Hide

ED: Reconsider after minor revisions (Editor review) (24 Mar 2017) by Corinna Hoose

AR by Ann Fridlind on behalf of the Authors (03 Apr 2017) Author's response Manuscript

ED: Publish as is (17 Apr 2017) by Corinna Hoose

AR by Ann Fridlind on behalf of the Authors (17 Apr 2017)

Download

Article (9360 KB)
Full-text XML

Short summary

Understanding observed storm microphysics via computer simulation requires measurements of aerosol on which most hydrometeors form. We prepare aerosol input data for six storms observed over Oklahoma. We demonstrate their use in simulations of a case with widespread ice outflow well sampled by aircraft. Simulations predict too few ice crystals that are too large. We speculate that microphysics found in tropical storms occurred here, likely associated with poorly understood ice multiplication.