Inter-comparison and evaluation of sea ice algorithms: towards further  identification of challenges and optimal approach using passive microwave  observations

Ivanova, N.; Pedersen, L. T.; Tonboe, R. T.; Kern, S.; Heygster, G.; Lavergne, T.; Sørensen, A.; Saldo, R.; Dybkjær, G.; Brucker, L.; Shokr, M.

doi:https://doi.org/10.5194/tc-9-1797-2015

Articles | Volume 9, issue 5

https://doi.org/10.5194/tc-9-1797-2015

© Author(s) 2015. This work is distributed under
the Creative Commons Attribution 3.0 License.

https://doi.org/10.5194/tc-9-1797-2015

© Author(s) 2015. This work is distributed under
the Creative Commons Attribution 3.0 License.

Articles | Volume 9, issue 5

Research article

|

15 Sep 2015

Research article |

| 15 Sep 2015

Inter-comparison and evaluation of sea ice algorithms: towards further identification of challenges and optimal approach using passive microwave observations

N. Ivanova, L. T. Pedersen, R. T. Tonboe, S. Kern, G. Heygster, T. Lavergne, A. Sørensen, R. Saldo, G. Dybkjær, L. Brucker, and M. Shokr

Download

Final revised paper (published on 15 Sep 2015)
Preprint (discussion started on 26 Feb 2015)

Interactive discussion

Status: closed

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

- Printer-friendly version

- Supplement

RC C229: 'Referee Comment on "Satellite passive microwave measurements of sea ice concentration: an optimal algorithm and challenges" by Ivanova et al.', Anonymous Referee #1, 16 Mar 2015
- AC C816: 'Response to the Anonymous Referee #1', Natalia Ivanova, 21 May 2015
RC C272: 'Review of “Satellite passive microwave measurements of sea ice concentration: an optimal algorithm and challenges” by Ivanova et al.', Walter Meier, 27 Mar 2015
- AC C826: 'Response to Dr. W. Meier', Natalia Ivanova, 21 May 2015
RC C443: 'Review of Ivanova et al, tc-2015-31', Josefino Comiso, 17 Apr 2015
- AC C837: 'Response to Dr. J. C. Comiso', Natalia Ivanova, 21 May 2015

Peer-review completion

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

AR by Natalia Ivanova on behalf of the Authors (17 Jun 2015) Author's response Manuscript

ED: Referee Nomination & Report Request started (03 Jul 2015) by Christian Haas

RR by Jan Lieser (30 Jul 2015)

ED: Publish subject to minor revisions (Editor review) (17 Aug 2015) by Christian Haas

Dear authors,

thank you for the careful revision of your manuscript. I feel that it is mostly good to go, but would like to ask you to consider the following changes/additions which should be easy to implement:

I feel that some of the important comments by reviewer 3 have not been sufficiently addressed in the text, even though you have extensively commented in your replies. I am particularly concerned with your treatment of biases, or lack of their consideration (Section 4.1 ff). While I can understand that you prefer to focus on variations around those biases, it would be nice to give at least some indication of what the biases of the different algorithms are. More importantly, the abstract should be clearer about what the parameters were to evaluate skill. What is skill in this regard? Maybe you can easily add one or two sentences to the abstract to clarify what you have studied (e.g. sensitivity to variations of boundary conditions/tie points?). And please verify your usage of “bias” throughout the text.

As remarked by the forth reviewer, the use of abbreviations and acronyms is confusing at times. Please verify that your use is correct, and consider to write out some acronyms which may not be used so often. It would be good to write out some acronyms in the conclusions at least, such that this section can be read independently. However, most importantly, please spell out abbreviations in the figure captions (with acronyms in parentheses so that they refer to axis labels), such that those are self-explanatory.

When discussing issues of melt ponds, I am curious myself as to whether these are only important during the melt season, or also afterwards, as the presence of refrozen ponds with their fresh ice and level surface markedly changes ice surface properties. Any insights on this?

P6, l15: add reference for MEMSL.
P7, l24: can you add a half-sentence to explain how the pdf is used, or what property of it?
P8, l18: calibration of what?

Please also carefully check the text once again for typos/misspellings, and the use of the word “the”.
Thank you and best regards

Christian Haas

Hide

AR by Natalia Ivanova on behalf of the Authors (21 Aug 2015) Author's response Manuscript

ED: Publish as is (24 Aug 2015) by Christian Haas

AR by Natalia Ivanova on behalf of the Authors (25 Aug 2015)

Short summary

Thirty sea ice algorithms are inter-compared and evaluated systematically over low and high sea ice concentrations, as well as in the presence of thin ice and melt ponds. A hybrid approach is suggested to retrieve sea ice concentration globally for climate monitoring purposes. This approach consists of a combination of two algorithms plus the implementation of a dynamic tie point and atmospheric correction of input brightness temperatures.