Assessing the impact of large volcanic eruptions of the last millennium (850–1850&thinsp;CE) on Australian rainfall regimes

Blake, Stephanie A. P.; Lewis, Sophie C.; LeGrande, Allegra N.; Miller, Ron L.

doi:https://doi.org/10.5194/cp-14-811-2018

Articles | Volume 14, issue 6

https://doi.org/10.5194/cp-14-811-2018

© Author(s) 2018. This work is distributed under
the Creative Commons Attribution 4.0 License.

https://doi.org/10.5194/cp-14-811-2018

© Author(s) 2018. This work is distributed under
the Creative Commons Attribution 4.0 License.

Articles | Volume 14, issue 6

Research article

|

18 Jun 2018

Research article |

| 18 Jun 2018

Assessing the impact of large volcanic eruptions of the last millennium (850–1850 CE) on Australian rainfall regimes

Stephanie A. P. Blake, Sophie C. Lewis, Allegra N. LeGrande, and Ron L. Miller

Download

Final revised paper (published on 18 Jun 2018)
Preprint (discussion started on 25 Sep 2017)

Interactive discussion

Status: closed

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

- Printer-friendly version

- Supplement

RC1: 'Review Comments for Blake et al.', Anonymous Referee #1, 03 Oct 2017
- AC1: 'Reply to Reviwer 1', Stephanie Blake, 04 Dec 2017
RC2: 'Comment on “Assessing the impact of large volcanic eruptions of the Last Millennium on Australian rainfall regimes ” by Blake et al', Anonymous Referee #2, 12 Oct 2017
- AC2: 'Reply to Reviewer 2', Stephanie Blake, 04 Dec 2017
SC1: 'Review of ‘Assessing the impact of large volcanic eruptions of the Last Millenium on Australian rainfall regimes’ by Blake et al.', Marte Stoorvogel, 04 Nov 2017
- AC3: 'Reply to Reviewer 3', Stephanie Blake, 04 Dec 2017

Peer-review completion

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

ED: Reconsider after major revisions (11 Dec 2017) by Stefan Bronnimann

AR by Stephanie Blake on behalf of the Authors (26 Feb 2018)

ED: Referee Nomination & Report Request started (07 Mar 2018) by Stefan Bronnimann

RR by Anonymous Referee #1 (13 Mar 2018)

RR by Anonymous Referee #2 (28 Mar 2018)

Suggestions for revision or reasons for rejection

Comment on “Assessing the impact of large volcanic eruptions of the Last Millennium on Australian rainfall regimes ” Revision 1 by Blake et al

The authors have addressed most of the comments . The revision has improved substantially from the original submission, especially by clarify the model performance and specific goal of this study. I would recommend acceptance for publication once the following issues are addressed:

1. Line 623
Please clarify the definition of "(July-September - JASON)".
2. Line 740-744
The claim of "a significant pIOD condition one year after major eruptions in all volcanically forced ensembles that persists until year 5" needs more solid demonstration. Currently in Figure 4, DMI anomaly in the CR ensembles barely touch the significant line at year +1, let alone the other years; DMI anomaly in the 2×G scenario is slightly higher but the forcing is larger than the reality. Please also verify the use of 0.6 standard deviation as the significant level. "Fig.2" referred in line 742 should be "Fig. 3".
3. Figure 5
Does "the mean of all volcanic ensembles" mean the average of four CR ensembles and one 2×G ensembles? I assume the forcing in 2×G is much larger than that in CR. Please discuss how does the forcing with different magnitudes affect your results.
4. Line 864-876
I do not find the added explanation of the mechanism underlying El Nino response satisfying. For example, how does "a uniform reduction in surface temperature" generate the El Nino-like anomaly? Why was it most visible in year +4?
5. Line 880-882
Please demonstrate in more detail how did the direct precipitation effect of volcanic aerosols override the impact of the IOD on Australian precipitation. Right now, the conclusion was based on the results found in previous studies without verification in this model. Which parameter represents the direct precipitation effect of volcanic aerosols in the GISS model? How was the override effect actually appear in this model results?
6. I found the use of "multi-model" misleading, since it is only based on one model.

Hide

ED: Publish subject to minor revisions (review by editor) (17 Apr 2018) by Stefan Bronnimann

AR by Stephanie Blake on behalf of the Authors (10 May 2018) Author's response Manuscript

ED: Publish as is (17 May 2018) by Stefan Bronnimann

AR by Stephanie Blake on behalf of the Authors (23 May 2018)

Short summary

We studied the impact of the six largest tropical eruptions in reference to Australian precipitation, the Indian Ocean Dipole (IOD), and El Niño–Southern Oscillation (ENSO). Volcanic forcing increased the likelihood of El Niños and positive IODs (pIOD) and caused positive rainfall anomalies over north-west (NW) and south-east (SE) Australia. Larger sulfate loading caused more persistent pIOD and El Niños, enhanced precipitation over NW Australia, and dampened precipitation over SE Australia.