The authors introduce a tangible interface for interacting with spatiotemporal Earth system data, consisting of a physical cube where the faces represent the intrinsic dimensions of analysis-ready data cubes, i.e., latitude, longitude, and time. As a Perspective, they successfully identify the challenge non-experts face when exploring increasingly complex and high-dimensional Earth system datasets. Their approach aligns well with the scope of Earth System Dynamics, particularly regarding novel tools and interdisciplinary communication.

The physical data cube is a novel and appealing concept that will be of significant interest to the community. I recommend the manuscript for publication, subject to minor revisions. The authors should focus on providing sufficient technical detail to foster community adoption, strengthen the conceptual arguments regarding the benefits of spatiotemporal reasoning, and critically reflect on the potential/limitations of the physical data cube.

1) The current hardware description is high-level. More details can be provided to ensure the tool is reproducible. Could you explain the technical connection between the overview monitor and the cube more comprehensively? Please also include a technical section or appendix with basic specifications (e.g., screen resolution, CPU/GPU requirements for low latency, etc.) to facilitate readers in assessing the feasibility of deploying this solution in institutions such as research centers and schools. 

2) The authors argue that current 2D visualizations constrain "spatiotemporal reasoning and intuitive understanding". Could you complete the discussion based on the cited literature on data physicalization (e.g., Jansen et al., 2015) to motivate why the physical cube aids scientific discovery?

3) Given the educational context, why can manipulating a cube of data be better for learning dynamics than spinning a globe? What could help users to mentally map the transition from the front face (map) to the side face (Hovmöller diagram)? Explicitly contrasting the "geometry-first" approach of a globe with the "data-first" approach of the cube would strengthen the educational argument.

4) While true for the data structure (array), geographically, the Earth is not a cube. Projecting a continuous sphere onto a cube creates discontinuities at the edges. Could you add a brief discussion on this and other limitations/constraints of the proposed tool? 

5) The validation of the tool reported in the manuscript is anecdotal ("we personally interacted with approximately 150 attendees at the cube over the week"). Could you report some specific qualitative assessments of feedback? For example, did users comment specifically on the speed of interaction or the clarity of the temporal dimension, among other aspects?

Overall quality of the preprint:

This is a preprint that is worth of publication.  It is well written and clearly describes a novel new technology.

This paper introduces an interesting tool for the display of multidimensional data, allowing user to interact with the data in three dimensions.  The rightly observe that these kinds of interactions have become more critical as the size and complexity of datasets has increased.  They build upon the developments in Lexcube (a 2-D visualization of datacubes) to crate a fully three dimensional physical data cube.  The physical cube is novel and fit for purpose.  While the paper focuses on the describing the details of the cube, they also describe the responses of users when they took the cube to a scientific meeting and touch briefly upon preliminary discoveries supported by the cube.  The level of detail is appropriate for a short communication.

Specific comments:

In a longer presentation of the cube a number of questions could be addressed:

1. What are the specifications for the supporting PC, monitors etc. of the cube?

2. What are the specifics of the size and complexity of datasets that could be visualized?

3. Are there ways to output the slices being visualized to allow for analysis beyond the visual analysis enabled by the cube?

4. While the strengths of the cube for education and outreach are clear, how might it be further developed to support scientific analyses?

Technical corrections and comments:

No notable corrections needed.  

Does the paper address relevant scientific questions within the scope of ESD?

Give this is more of a technical paper, it answers important technical questions about the visualization of multidimensional scientific data clearly in a unique tool.

Does the paper present novel concepts, ideas, tools, or data?

Yes, the cube is definitely novel.

Are substantial conclusions reached?

The reactions of users of the cube show substantial benefits and clear understanding of how to use the cube. 

Are the scientific methods and assumptions valid and clearly outlined?

N/A

Are the results sufficient to support the interpretations and conclusions?

Yes, the system is clearly described and 

Is the description of experiments and calculations sufficiently complete and precise to allow their reproduction by fellow scientists (traceability of results)?

N/A

Do the authors give proper credit to related work and clearly indicate their own new/original contribution?

Yes.

Does the title clearly reflect the contents of the paper?

Yes.

Does the abstract provide a concise and complete summary?

Is the overall presentation well structured and clear?

Yes.

Is the language fluent and precise?

Yes.

Are mathematical formulae, symbols, abbreviations, and units correctly defined and used?

N/A

Should any parts of the paper (text, formulae, figures, tables) be clarified, reduced, combined, or eliminated?

More detail on the technical specification of the cube would be helpful.

Are the number and quality of references appropriate?

Yes.

Is the amount and quality of supplementary material appropriate?

The video is helpful but could be expanded to describe actually data explorations, going beyond simply illustrating the capabilities of the cube.