Knowledge Gaps and Impact of Future Satellite Missions to Facilitate Monitoring of Changes in the Arctic Ocean

Round 1

Reviewer 1 Report

This manuscript presents a description of the current state of observational satellite systems focused on the factors of the climatic state in the Arctic latitudes. Their capabilities and shortcomings are demonstrated, which limit the possibilities of their full use in the study of the climate of the Arctic. In addition, planned and approved future space missions are presented, designed to significantly improve the quality of ongoing satellite observations. Overall, the quality of the presented review can be judged on the condition of a detailed knowledge of the details of space programs and the capabilities of measuring equipment, which I do not have. However, for me, as a climate researcher, it is extremely important to have a complete picture of developments in this area. This is exactly what this work gives and therefore I am grateful to the authors for their review article, and I believe that this manuscript should be published.

As remarks, I can only put forward the careless design of the tables and the poor quality of the figures, which makes it difficult to perceive them.

Author Response

Dear reviewer,

Thank you for your review on our paper.

We have taken into account your comments and improved the tables and figures design.

Reviewer 2 Report

To the authors:

This is an information paper for the present and future satellite sensors for the Arctic Ocean observations.

Reading the whole text, the title seems to be unreasonable since there is no description of “changes in the Arctic Ocean”.  Also, most of the satellite missions described were of EU’s.

You should explain about the “Arktalas Hoavva” project. (Line LN29, LN83, LN102, LN107, LN135)

And I am wondering there is no expression with this project in Conclusion.

Figure 2 and 3, Sankey diagrams are very informative; however, they seem to be too noisy, and you should select much beter color bars.

Chapter 3 and 4 are so busy, and you need to show another table, similar to Table 1 but showing for each satellite mission, against sensors (visible, IR, MW bands, radar, and so on), with duration terms and applications.

Only very few descriptions are shown for NASA or US satellite missions, due to ESA funded project?

(minor comments)

-       LN135: What is “this” mean?

-       LN138: What is “native resolution”?

-       LN151-169: I could not understand why you related to the Arctic Amplification (AA) in this paragraph.

-       LN189: What is “this” mean?

-       LN201-207: It is not clear how AA impacts the atmospheric and ocean circulation.

No line number below!

-       5p, lines 12 to 14: It means that the calibration is incomplete for those sensors/ data.

Author Response

Dear reviewer,

Thank you for your review on our paper. Please find below the response to your comments.

• Change the title since there is no description of “changes in the Arctic Ocean”

>> We changed the title to “Knowledge gaps and Impact of future satellite missions to facilitate monitoring of changes in the Arctic Ocean”

• Explain about the “Arktalas Hoavva” project

>>We describe the project though the four ASC in the Introduction, yet we made minor changes referring to the other seven publications, l.96-102:

These ASC´s are particularly presented and discussed in seven scientific publications emerging from the Arktalas Hoavva project [12, 13, 14, 15, 16, 17 and 18], to be further out-lined in Section 2. In this paper we address the state-of-art satellite observations of the Arctic Ocean in the context of the Arktalas major scientific challenges in Section 2. In Section 3, we focus on the assessment of the limitations and gaps of the current and past satellite measurements in view of the four  challenges. The capabilities of future missions are then addressed in Section 4, followed by a summary and conclusion in Section 5.

• Sankey diagrams should be less noisy with better color bars

>> Following your comment, we have improved the Sankey diagram in order to ensure better readability. Color bars have homogenized in order to keep a single color for each variable of interest. The noise in the figure was due to a change of format, this has now been resolved.

• Chapter 3 and 4 are too busy, show another table, similar to Table 1 but showing for each satellite mission, against sensors (visible, IR, MW bands, radar, and so on), with duration terms and applications.

>> We fixed this in our review.

• Add description for NASA/US missions

>> We added justification l.75-79 :

This choice is made to reduce the complexity and improve the readability of the figure presentations of the results, without excluding the major applications areas. The availability of relevant and similar type sensor data from missions planned by the other countries will complement and expand the availability of satellite missions to be available for future studies of the Arctic Ocean.

• LN135: What is “this” mean?

>> Based on this the Arktalas Hoavva study project; it has adapted  a stepwise multi-modal analyses framework approach to address the four major Arctic Scientific Challenges listed above

• LN138: What is “native resolution”?

>> Native resolution refers to the product pixel size as per the satellite capability. Higher-level products might have a lower resolution due to temporal/spatial averaging, data combination etc. Native resolution is a widely used term in the satellite community.

• LN189: What is “this” mean?

>> In this context, it refers to thinning sea ice. We have completed the manuscript in order to ease the understanding.

• LN201-207: It is not clear how AA impacts the atmospheric and ocean circulation.

>> This was indeed not critical to include here. The AA reference  has been deleted.

• No line number below 207

>> We corrected this in the revision.

Reviewer 3 Report

Comments attached. 

Comments for author File: Comments.pdf

Author Response

Dear reviewer,

Thank you for your review on our paper. Please find below the response to your comments.

• State that the paper is focused on sea-ice dynamics and ocean topography (SSH and SSS), rather than ocean biology and ocean-atmosphere focused research

>> We feel that we clearly state the objectives of Arktalas Hoavaa (ASC1-4).

• We should remove the sections relating to phytoplankton (and specify/refine introduction) or add references

>> We think this is still valid when mentioned in relation to CHIME

• We should discuss Lidar and discuss the benefits/data from ICESat and CALIOP onboard CALIPSO

>> We added it in Figure 1.

• Ln 27: ‘regarding’ > “we provide a state-of-the-art review of…”

>>We agree with the proposed change and made the correction in the abstract.

• Consistent spelling of in-situ

>> We have corrected the spelling of the “in-situ” word to ensure consistency throughout the document

Round 2

Reviewer 2 Report

The manuscript was greatly improved and became suitable for publication in the journal. Especially, the figures are greatly improved.