In the submitted paper authors investigated difference between the rainfall erosivity map prepared based on the high density hourly rainfall records and map prepared by Yin et al. (2019). The paper is probably in the scope of the Earth System Science Data and the investigated topic (i.e. rainfall erosivity) is of general importance for the soil (erosion) science. However, I think that the paper would need to be much better organized in order to be accepted for publication in the ESSD. Thus, often it is very hard to follow the methodological description and discussion of the results. Additionally, I think that authors should clarify what are the “true” rainfall erosivity values and I think that a rainfall erosivity map cannot be regarded as a “true” rainfall erosivity. Please see below comments for further details. Therefore, I think that authors should significantly improve the presentation of their scientific work and after that a better evaluation of the scientific quality would be possible. Some specific comments are provided below.
Please note that these comments correspond to the “clear” version, without track changes and that I have not reviewed this manuscript in the first stage.
L98: What was the threshold used to estimate that data is too short? How was the adjustment done?
L131-132: Please rephrase this sentence and add a reference
L135: Why not 12.7 mm?
L142-143: Please rephrase this description since it is not very clear at the moment.
Pages 7 and 8: In general description of the methodology is a bit confused, for example you use Rhour and Rh, you use the term effective years, the formulation of eq. 1 is strange, you have EH60 on both sides of the equation, etc. I suggest that the methodology (and the description) should follow some kind of logical order, for example start with 1-min data, then hourly data and then daily data or vice versa. Now you start with hourly, then you have EI30, then 1-min and then daily. In between, you introduce all sorts of correction factors that come almost out of nowhere. Thus, as a reader you are guessing where the numbers came from. You actually have some results in between. For example, L179 is obviously something that was done and is presented here in the methodology part. Therefore, the methodology should present only data and methods and results should be presented in some other section.
L199: “good” this is subjective, please quantify it and I suggest to avoid using such terms.
L214-215: Yin et al. map was used as a reference, I understand this part, but I cannot understand how were you then able to evaluate the improvement? If you have a reference, then you compare your new map with it but you cannot say that something is better or worse than your reference? From my point of view, what you could compare are station-based values. Thus, as there is mentioned somewhere in the paper, the best estimate of the rainfall erosivity can be obtained using data obtained from the optical disdrometers (speed and drop velocity estimates), then probably 1-min precipitation data using KE-I equation can yield a reasonable fit. Hourly and daily data should be even less accurate. When you interpolate there is always an additional error due to interpolation. Thus, I am not sure if such approach as mentioned here can be useful? Therefore, I am not sure if you can easily merge maps with station-based data and do a comparison (grid-cell value is not the same as station-based point value)?
Figure 3: Where is the 1-minute data here?
L243-244: How is this possible? If Yin et al. map is reference, compared to what you were able to show an improvement?
L245: Underestimated compared to what? Additionally, if I understand correctly, you considered 1-min data as “true” and how did you obtain other values? Why maps are mentioned in Figure 4? I think that you cannot just compare station-based gauge data with corresponding values obtained from the interpolated maps since interpolation has an effect on these values?
L248: Here again you talk about relative errors of the maps?
Section 3.3: Again, you discuss improvement of the map, but since “true” spatial rainfall erosivity is not known I think that this should be rephrased. You can only compare two maps but you cannot say that one of the two is “true” since the interpolation will always introduce some error. From my points of view, “true” erosivity can only be either disdrometer data or perhaps 1-min precipitation data based erosivity estimates. I think that map can be regarded as true erosivity.
Figure 10: Here you compare hourly and 1-min data, how exactly is this different from the Figure 4 where you had “R-factor from the map in this study”? As mentioned, there is sometimes hard to follow the results and discussion. Please modify so that it will be easier to follow the results and discussion.