The article is appropriate to support the publication of the dataset. The authors used standard methods, well described and referenced. The data presented represent a novelty in the field, so that the potential application and correlation with direct investigations and researches conducted in the area appears obvious to the terrestrial permafrost scientific community.

The dataset is competitive and accessible via the given Zenodo identifier. The state of the art in data collection and processing is adequately described. The dataset is significant, useful and complete.

The dataset is usable in its current format and size. Adequate space is used to describe the data, their organisation and possible processing, including appropriate examples. The overall structure of the paper is well organised and clear. A minor revision of the language is suggested.

About uniqueness, costly data sets such the one supported by the authors are not easily replicable for financial reasons.

Variations in permafrost conditions due to climate change are strongly influencing Arctic hydrology, although the implications are not yet well understood. Such a dataset could help to better frame the high quality research area around Ny-Ålesund and open the way to advanced multidisciplinary knowledge. Some minor revisions are suggested in the Supplement document attached.

The paper titled "A new repository of electrical resistivity tomography and ground penetrating radar data from summer 2022 near Ny-Ålesund, Svalbard" contributes interesting geophysical dataset  to the scientific community, particularly from the Ny-Ålesund area, which has been lacking due to logistical challenges in remote polar regions. The dataset, comprising ERT and GPR surveys, provides an opportunity to deepen our understanding of subsurface dynamics in the Arctic. The dataset is easily accessible via the provided Zenodo identifier, and it is well-organized and user-friendly. However, while I acknowledge the dataset's potential relevance, further discussion regarding its implications, potential applications, and avenues for future research could enhance the value of this contribution and facilitate interdisciplinary collaborations. The current presentation resembles more of a technical report rather than a scientific discussion of dataset.

Abstract:

Incorporating a brief mention of specific findings or insights gained from the dataset, even if preliminary, would provide readers with an overview of the study's potential implications.

Introduction:

The introduction could benefit from expanding on other geophysical methods commonly used in Arctic environments, such as seismic and EMI, while discussing why certain methods were chosen by authors, and also addressing potential limitations or uncertainties associated with their applications in such regions. Additionally, previous geophysical studies in the region (if any) should be discussed to highlight the novel contributions of this new data repository. Furthermore, elaborating on how this dataset can contribute to addressing existing gaps in knowledge about groundwater flow dynamics, active layer and permafrost (the aim of paper as suggested by authors) in Arctic regions would contextualize its significance within the broader scientific community.

Study Area:

The authors have included numerous references to previous geophysical studies in this region within this section. In my view, this content would be better placed in the introduction to complete the literature review and further justify the necessity of this new geophysical data repository. Currently, the section presents a lengthy list of references without establishing a clear connection to how these studies are related to the better understanding of “study area”. On the other hand, the section lacks detailed and specific information regarding the characterization of the study area, which is essential in my opinion to justify the applied geophysical methodology and array configuration. For instance, while the aim of the investigation appears to be the characterization of groundwater flow in relation to the active layer and potentially through or below the permafrost, there is a notable absence of information concerning the permafrost, active layer dynamics, and groundwater in this section. Information regarding the expected spatiotemporal variability of the active layer, the nature of the permafrost (e.g., continuous or discontinuous) and it is extension, and climate data are absent! Information about climate data play a significant role in the dynamic interactions between groundwater, the active layer, and permafrost. Furthermore, the potential availability of borehole data in this region could provide valuable insights into permafrost conditions and potential degradation. Access to such information would enable readers to better understand the rationale behind the choice of geophysical methods and array design, particularly concerning the trade-off between resolution and depth of investigation and also interpretation of data and modelling results.

Geophysical Surveys:

The authors could provide additional insights into the rationale behind the chosen survey configurations, such as the use of electrode spacing of 1 and 10 meters. e.g. whether the smaller spacing is intended for active layer characterization and larger spacing for permafrost? Moreover, detailing the challenges encountered during the surveys using ERT and GPR conducted in this region, data noise and uncertainties, modelling error would not only assist researchers to understand the limitations of data but also benefit those engaged in geophysical prospecting in polar and remote areas for potential improvement.

ERT:

Further information regarding contact resistance data would be valuable if available. This could include typical values observed during ERT surveys, the efficacy of bentonite solution in mitigating contact resistance, and any experimentation with other alternatives such as salt water. Additionally, details on electrode type and dimension, the establishment of threshold values for contact resistance filtering, and the extent of data filtered based on each criterion (e.g., negative values, contact resistance, outlier) and in total would be useful. Such insights contribute to our understanding of best practices for ERT surveying and data processing in permafrost regions. See for example

Herring, T., Lewkowicz, A.G., Hauck, C., Hilbich, C., Mollaret, C., Oldenborger, G.A., Uhlemann, S., Calmels, F., Farzamian, M., Calmels, F., and Scandroglio, R. 2023. Best practices for using electrical resistivity tomography to investigate permafrost, Permafrost and Periglacial Processes, 34, 4, 494-512, https://doi.org/10.1002/ppp.2207.

While acknowledging that this is primarily a data-based publication, I suggest that the authors go a bit deeper into the interpretation of ERT examples. This includes presenting how resistive values are interpreted (based on available data), their lateral and vertical variability, quantifying average resistivity changes across different sites and depths of investigation, and exploring potential subsurface factors influencing and explaining variability. While direct measurements of electric resistivity in the investigated area seems not be available, some additional information such as borehole data (if available) can help with interpretations of resistivity data and facilitate broader utilization of this dataset.

GPR:

From the text It's unclear whether the surveys were conducted continuously or manually, and whether the antenna was pulled or measured at specified distances (for both antennas). Given that these antennas are not typically designed for rough terrains, it's worth discussing if the authors encountered any additional challenges during data collection and processing, particularly regarding ensuring proper surface contact and if those challenges impacted data quality.

Additionally, it's unclear whether the same processing steps discussed apply to both antennas or specifically to the 400 MHz frequency. Furthermore, there is an absence of example presentations of GPR data from the low frequency of 40 MHz. Incorporating such examples would offer a more comprehensive understanding of the collected GPR data and also comparison with deeper ERT surveys with 10m electrode spacing.

A preliminary interpretation of the GPR results presented in Figure 8 would be beneficial, particularly considering that the surveys were conducted in a piezometer area. I miss any information about piezometer area and if they are available and how they could guide on survey design and interpretations afterward.

Is there any available information from the site that could assist in estimating the dielectric constant, even if only roughly, to enable estimation of the depth of reflections? Alternatively, has there been any calibration conducted over known buried targets? Could piezometer data from the study area be used for this purpose?

MT:

The current statement about MT may not offer significant insight into the source of the problem. Thus, I recommend either including more information about the equipment, survey design, and even including datasets or removing this section and briefly mentioning it in the introduction.