A Google Earth Engine Platform to Integrate Multi-Satellite and Citizen Science Data for the Monitoring of River Ice Dynamics

Round 1

Reviewer 1 Report

Manuscript: remotesensing- 2908883

General comments: The manuscript titled ‘A Google Earth Engine Platform to Integrate Multi-Satellite and Citizen Science data for the monitoring of River Ice Dynamics’ is a paper presenting an open-source system for monitoring river ice dynamics in Alaska integrating citizen science with multi-satellite remote sensing observations. The manuscript is well written and describes the system in great detail along with the several use case scenarios. The manuscript just needs a few modifications but I recommend this manuscript for publishing in the journal. Here are my comments:

Comment #1: [Line 112-116] Can you please double-check whether the sentences are not repeating? It seems like the two sentences here are repeating or I was not able to understand what the authors differently in these two sentences.

Comment #2: [Line 252] Typo with the sentence repeating – ‘enhancing the timeliness and relevance of the data for users and decision-makers.’

Comment #3: [Line 401] I suggest showing locations of these 165 citizen science observations from data preprocessing.

Comment #4: Is there a user guide for general users that will be posted on the online portal? Because some of the Sentinel-1 imageries are difficult to interpret by general users who are not familiar with the processed SAR imageries.

Author Response

Thank you for taking the time to review our manuscript and provide valuable feedback. Our detailed responses are provided in the attached file for your review.

Author Response File: Author Response.pdf

Reviewer 2 Report

This study integrated multisource remote sensing and citizen science to monitor river ice dynamics in the under-observed north regions, which is meaningful and interesting. Below are some suggestions and questions, which I hope will help improve this ms.

L16-20: These two sentences are somewhat repetitive.

L25: Please provide the full name of RS.

Please consider including info on the used remote sensing data and methods in the abstract.

The materials and methods section is hard to follow, as you mixed data processing and algorithm description. Please consider using a common structural organization: describe the data first, then the algorithms/platforms.

I cannot find any detailed description of the satellite data used in this study. What types of L8/9, S2 data were used, top of atmosphere or surface reflectance? Which bands were included in the algorithm?

L252: which paragraph did this sentence belong to?

What is the purpose of integrating Sentinel-3?

How did you deal with the inconsistent spatial resolutions of the satellite data used?

What is the spatial resolution of the final ice map?

Table 1: please add a column indicating the type of remote sensing (optical, SAR, etc.) for each satellite data.

Each result section is too long and hard to follow; it is more like a report than a scientific article. You may try to break them up into more sub-sections, like User interface of the river ice monitoring system, Accuracy assessment, Spatial and Temporal Analysis of Ice Conditions, citizen science … etc.

In the section “Spatial and Temporal Analysis of Ice Conditions”, as shown in Figure 6, the authors only conducted qualitative analysis for the seasonal transition of different water statuses. Can you also provide a quantitative analysis of those water status, for example, monthly composite and change analysis?

Author Response

Thank you for taking the time to review our manuscript and provide valuable feedback. Our detailed responses are provided in the attached file for your review.

Author Response File: Author Response.pdf

Reviewer 3 Report

I have no further comments on this manuscript.

Author Response

Thank you for taking the time to review our manuscript. Our detailed responses are provided in the attached file for your review.

Author Response File: Author Response.pdf

Round 2

Reviewer 2 Report

This manuscript has been greatly improved. One minor suggestion: please also include responses to the questions (the purpose of including Sentinel-3, the spatial resolution of the final ice map) in the manuscript, rather than just including them in the response letter, to make them clearer to the broader readers.

Author Response

Thank you for your thorough feedback in both the first and second rounds of review. We have carefully considered your comments and have made corresponding changes to our manuscript, highlighted in blue for responses and in red for revisions. We believe these updates have greatly enhanced our paper.

This manuscript has been greatly improved. One minor suggestion: please also include responses to the questions (the purpose of including Sentinel-3, the spatial resolution of the final ice map) in the manuscript, rather than just including them in the response letter, to make them clearer to the broader readers.

Thank you for your comment. We have added the suggested information to the manuscript, including a detailed paragraph that addresses the purpose of including Sentinel-3 and the spatial resolution of the final ice map. This addition also clarifies the usage of Sentinel-3 within our system, as illustrated in Figure 9.

In section 3.1, the following paragraph was added:

“It is important to highlight that, within our interface, users have the flexibility to individually display remote sensing products by activating the desired product (Figure 4). High-resolution optical products like Sentinel-2, Landsat-8, and Landsat-9 provide detailed imagery of land cover, enabling the detection of ice in both large and narrow channels. Conversely, moderate resolution optical products, such as the VIIRS river ice (375 m) product and Sentinel-3 (300 m), are more suited for monitoring ice conditions over mid-sized and large rivers only. During the development of our system, the use of low-Earth orbit sensors like VIIRS onboard the NOAA-20 spacecraft and SLSTR onboard of Sentinel-3 was instrumental. Despite their moderate resolution, these sensors can rapidly acquire data on a global scale. Furthermore, the inclusion of Sentinel-3, akin to VIIRS observations, significantly enhances our system with its daily temporal and continental-scale spatial coverage.”

Author Response File: Author Response.pdf