The study aims to improve the understanding of how groundwater affects regional temperature anomalies by comparing the simulation results from TSMP and those from the other RCMs. Although the topic and method are of interest to the readership of Earth System Dynamics, several issues need to be addressed. First, the manuscript is poorly written because of many confusing and inaccurate sentences. Second, the results are not new since there already have been comparations in heat event analyses between TSMP and the other RCMs. For example, in line 60, “In fact, many RCMs overestimate the frequency, duration, and intensity of heat waves (e.g., Vautard et al., 2013; Lhotka et al., 2018)”, or in line 255, “Vautard et al. (2013), Plavcová and Kyselý (2016) have previously found a systematic tendency of most RCMs to overestimate the number and duration of long heat waves in comparison to observations”. Meanwhile, the key results showing characteristics of heat waves/events are not well organized for the readers to follow. Third, comparisons between the simulation results of TSMP and the ensemble of RCMs (Figure 5) are not convincing to conclude the influence of groundwater, since the different conceptualizations of physical processes among the models can also result in differences in temperature anomaly, let alone different forcing data (Table 1). Fourth, TSMP has the advantage of fully characterizing groundwater-soil moisture-temperature interactions. Still, the manuscript fails to analyze more variables of the model outputs rather than temperature anomalies. It fails to investigate why and how groundwater can affect the characteristics of extreme heat events. Please find the specific comments as follows:

1. Title: Is that suitable to say “climatology of extreme heat events”? since this work is talking about the climatological characteristics/mechanisms of extreme heat events.
2. Line 1: This sentence is not concise. Particularly, it seems unnecessary to talk about the requirements of high-resolution climate data, which is not the point of this study’s focus. The potential background might be why groundwater processes can affect extreme heat events for the second sentence.
3. Line 4: What do you mean by a unique dataset? How unique?
4. Line 5: Not all readers know what EURO-CORDEX is.
5. Line 6: It should be “period of 1976-2005”
6. Line 8: What is the respective evaporative regime? And in the following sentences, regional differences are not mentioned.
7. Line 9: Are “the other RCMs considered” just the CORDEX ensemble?
8. Line 13: Not rigorous for using “slightly more”
9. Line 13: Although it has been explained that a heat event with a duration exceeding 6 days indicates a heat wave, what are high-intensity heat waves?
10. Line 15: First, using simplified might be better than using “explicit”? Second, it seems hard to conclude “rarer and weaker heat waves” since the frequency of heat waves and high-intensity heat waves is higher for the CORDEX ensemble, where only single-day heat events happen less often. Third, as mentioned above, are the RCMs in this study mean the CORDEX ensemble?
11. Line 15: what do you mean about “also in climate projections”?
12. Lines 44-49: These are not informative or conclusive enough to be an independent paragraph.
13. Introduction section: Overall, this section is relatively clear about the importance of soil moisture in groundwater-soil moisture-temperature coupling, which affects temperature anomaly, and the advantage of groundwater parameterizations in TSMP. However, it is not firmly linked to the manuscript’s aim to study the statistics of the heat event characteristics (frequency, duration, intensity).
14. Model section: The introduction of TSMP could be simplified, while the setup of TSMP could be clearer for reproducibility.
15. Line 105 and 108: It is unclear in which period the model was warmed up.
16. Lines 112-115: Is the model calibrated by well observations of the water table or observation-based surface temperature datasets? And how accurate are the simulation results?

Poshyvailo-Strube and colleagues investigated how the inclusion of groundwater modeling would affect heat wave characteristics in Europe. This is an important topic as groundwater plays a critical role in land-atmosphere interactions, but its modeling has been oversimplified or neglected in climate models. However, before I recommend publication, I have two major concerns that need to be addressed by the authors. Hope they will be useful to the authors.

1. The title seems to suggest that this paper will be providing and evaluating a new climatology of extreme heat events in Europe. I would expect the authors to compare their new climatology to observation-informed heat wave characteristics. However, I did not find any comparison with observations. The paper itself seems to discuss how groundwater modeling would affect heat waves just by comparing their model to other no-groundwater models. This seems not new to me as the authors have stated in line 60. An opportunity to improve probably is to add an observational perspective. Are the heat wave characteristics modeled by TSMP better agree with temperature observations than other models and by how much?

2. The current paper lacks an investigation of which process the groundwater had the influence to change the temperature anomalies. The intuitive processes are soil moisture and evapotranspiration. The comparison between TSMP and other RCMs may not be entirely due to groundwater. Other factors such as forcing, and structure differences (how they model vegetation) may also contribute to the difference. An opportunity to address this is to run the TSMP without the groundwater component and compare the affected processes within TSMP rather than across different RCM settings.