Seasonal and Ephemeral Snowpacks of the Conterminous United States
Round 1
Reviewer 1 Report
In my original review I recommended either a) to publish article as a short communication / technical note (not as research article), if such option is available b) to rework it into review paper by extending discussion of the relevant processes and/or of socioeconomic impact.
The author made effort to effort to expand analysis by looking into hydrological consequences of the changing snow cover. While it still lacks novelty in its analysis, I think it may have value as a review article providing a broad overview of snow cover distribution over lower 48 states and methods used to characterise it for people unfamiliar with the field.
Author Response
Author response to reviewer comments
In my original review I recommended either a) to publish article as a short communication / technical note (not as research article), if such option is available b) to rework it into review paper by extending discussion of the relevant processes and/or of socioeconomic impact.
The author made effort to effort to expand analysis by looking into hydrological consequences of the changing snow cover. While it still lacks novelty in its analysis, I think it may have value as a review article providing a broad overview of snow cover distribution over lower 48 states and methods used to characterise it for people unfamiliar with the field.
I appreciate the reviewer’s suggestion regarding changing the manuscript type. As I noted in my prior response, I will defer to the journal editor(s) to select the format of the manuscript and re-affirm that I am fine with any format (review, article, or technical note).
I maintain that the novelty of the manuscript lies in: (1) the application of the snow seasonality metric as applied across the conterminous US and (2) the application of the UA SWE product to evaluate locations of seasonal and ephemeral snow. To my knowledge, neither analysis has been performed. Nor has the third potentially novel aspect of the manuscript, (3) the brief evaluation of minimal SWE and seasonal snow and the volume of water no longer stored in seasonal snowpacks under these conditions as a first-pass approach at identifying small watersheds at risk of losing water stored in seasonal snow. If I am wrong on any or all of these fronts, citations in support of my erroneous interpretation would be greatly appreciated. Last, several additional references and discussion on the impacts of changing snow seasonality were added following the reviewer's suggestions at the prior stage.
I welcome additional specific suggestions for improving the novelty of the manuscript, but at this stage after peer review, I believe the paper provides additional insight to the field of hydrology in the United States to warrant publication. I did not receive clear guidance from the journal editorial staff as to precisely what they would like to see improved in the manuscript following the reviewer's comments (beyond ascribing minor revisions at the second review, which I interpret as not requiring substantial additional work). If the editors feel it is not sufficiently novel or of a sufficiently high standard for publication at this stage in this journal, that is OK with me and I have no qualms with withdrawing the paper and re-submitting to another journal. Again, I thank the reviewer for their time in reviewing the manuscript.
Reviewer 2 Report
Please check the grammar and figure references carefully. Several examples which need to be corrected are listed below.
line 93: 'to highlight similarities and differences between two simple to calculate'
line 206: 'the Sturm-classified seasonal snowpacks (cf.Figure 2.'
line 269: 'The differences between snowpack types grows larger in the upper percentiles'
Author Response
Author Response to Reviewer 2 (italics for emphasis)
Please check the grammar and figure references carefully. Several examples which need to be corrected are listed below.
Thank you for providing the noted example corrections and requesting me to perform an additional check on grammar and figure references. I have gone back over the manuscript and revised both accordingly.
line 93: 'to highlight similarities and differences between two simple to calculate'
Fixed: “…in order to highlight similarities and differences between these…”
line 206: 'the Sturm-classified seasonal snowpacks (cf.Figure 2.'
Fixed: “(cf. Figure 2b).”
line 269: 'The differences between snowpack types grows larger in the upper percentiles'
Revised to: “The differences between snowpack types diverge as one moves upwards from the lower quintile into the upper quintile of the distributions.”
This manuscript is a resubmission of an earlier submission. The following is a list of the peer review reports and author responses from that submission.
Round 1
Reviewer 1 Report
The author presents a technical note comparing two indices of the snowpack seasonality.
The note is very well written. However, it lacks scope and depth to be considered a research article. It applies the indices to a relatively limited dataset to draw largely trivial conclusions about snowpack zonation across contiguous US. The amount of new information presented within the article is dwarfed by the external sources. At the current state it is much closer to the review paper than to the research article (though, it still falls short).
I recommend either a) to publish article as a short communication / technical note (not as research article), if such option is available b) to rework it into review paper by extending discussion of the relevant processes and/or of socioeconomic impact
Line-specific comments:
Line 249-266 The impact of chinooks (foehns) on the snowpack on the prairies is known for over a century (e.g. Burrows, A.T., 1903. The chinook winds. J. Geog. 2, 124–136. doi:10.1080/00221340308985932 )
Author Response
Please see the attachment.
Author Response File: 
Author Response.pdf
Reviewer 2 Report
Comments to the authors:
The reviewer would like to thank the author for submitting this manuscript. This work has got good potential in the domain of cryospheric investigation. The manuscript can be further improved by including the comments.
Line 1:
The reviewer would like to understand the significance of the word “Conterminous”. This can be omitted unless necessary.
Line 2:
Can you use “spatial resolution” instead of “horizontal resolution”? Furthermore it is advised to clearly mention the source of the data instead of just “reanalysis product”.
Line 3:
The author calculated the “seasonal extent of the snowpacks...”.
Line 7:
“By relaxing the depth...”
The author is requested to reconsider if this sentence is necessary in the abstract. In summary, the author is requested to rewrite the abstract since the objective of the paper is not clearly conveyed in the abstract. The author employs the established mentors to calculate the snow extent. It is therefore necessary for the author to clearly highlight the original contribution in this paper.
Line 18:
“With a seasonal volume of snow of approximately 9,000 Gt...”
This information can be omitted.
Line 20:
“Myriad”
This word is unnecessary.
Line 68:
“Using observational data derived from satellite measurements...”
The author is requested to cite the following articles discussing satellite observation of snow cover extent.
-Bernier and Fortin, “The potential of time series of C-band SAR data to monitor dry and shallow snow cover”, IEEE TGRS, 1998.
-Kelly et al., “A prototype AMSR-E global snow area and snow depth algorithm”, IEEE TGRS, 2003.
-Hall et al., “Assessment of the relative accuracy of hemispheric-scale snow-cover maps”, Annals. Of Glaciology, 2017.
-Muhuri et al., “Snow cover mapping with polarization fraction variation using temporal RADARSAT-2 C-band full-polarimetric SAR data over the Indian Himalayas”, IEEE JSTARS, 2018.
-Gascoin et al., “Theia Snow collection: high-resolution operational snowcover maps from Sentinel-2 and Landsat-8 data”, Earth System Science Data, 2019.
Line 89:
The author is requested to specify if the duration of a “water year” is applicable for both the northern and the southern hemisphere. Furthermore, why are glaciated and permanently snow-covered regions exempted from the UAswe dataset? Considering this exemption in such areas from the dataset, how is the analysis presented in this paper a comprehensive one?
Line 99:
The author is requested to mention how the snow depth of at least 50 cm is obtained for the Sturm method over such a large spatial scale. Can the author add such a snow depth map in the manuscript? Furthermore, how does this method handle snow cover in forested areas where the snow presence/absence ambiguity is high in snow cover maps supplied by the satellite based methods.
Fig. 1:
The author is requested to redo the legend since the difference between the areas with ephemeral, seasonal, and snow-free is not clearly indicated. Furthermore, if the glaciated and permanently snow-covered regions exempted from the UAswe dataset how are such regions handled in the maps shown in Fig. 1? The author is also requested to explain why Alaska is excluded from this analysis since it is one of the major snow covered regions in the US.
Fig. 3:
The reviewer would like to point out that the discussion for Fig. 3 with respect to the observation is not comprehensive. The author discusses the mountain ranges. However, the maps don’t show them and neither all the readers are aware about the geographical location of these ranges. The author can simplify this discussion by dividing the US into northern and central parts. Furthermore, the author should also discuss the significance of the observation of Fig. 3 and not merely report these observations as they appear. What does “count of years” actually indicate and why is it different for the method/metrics?
Line 226 and Line 229:
“By providing insulation...”
“Further, shallow but persistent...”
The reviewer is unable to understand the inclusion of these sentences in the light of the results presented in the manuscript. The author is requested to discuss the important personal observations.
Line 249:
“Curious finding”
The author is requested to avoid using such terminology in a technical manuscript.
Line 282:
What does the author mean by “fine fuels”?
The author is also requested to rewrite “Winter recreation opportunities...” since it is not clear in this sentence what the author means by the term “periphery of long-duration snowpacks”.
Line 297:
The term “Concluding Remarks” is seldom noticed in a technical manuscript and more often it is the term “Conclusion” that is generally used.
Line 309:
The author is requested to use a more technically accepted term like “retention” in place of a more literary attractive term like “refugia”.
Line 320:
The author is encouraged to avoid using terms like “I used” and “I recommend” in a technical article and reframe such sentences in the manuscript.
Author Response
Please see the attachment.
Author Response File: Author Response.pdf
Reviewer 3 Report
I don't often do this when reviewing a manuscript, but I don't have a thing to improve. Very nice work.
Author Response
Please see the attachment.
Author Response File: Author Response.pdf
Reviewer 4 Report
- Introduction Section: please briefly explain why Sturm and SSM approaches are used in this paper instead of the other methods to identify seasonal snowpacks.
- Introduction Section: please state the innovation of this paper.
- Introduction Section: please add the outline of this paper.
- Line 124-130: is the overlap areas between SSM and Sturm approach the same as the area from Sturm approach? If not, please also explain why some areas are identified in SSM but not in Sturm approach.
- Figure 4: please also explain why the SSM and Sturm don’t agree well on high latitude such as 48 and 49 degrees North.
- Figure 5: please all add the elevation map.
- Line 237: Figure 2 doesn’t have c-d sub figures, please correct this.
Author Response
Please see the attachment.
Author Response File: Author Response.pdf
