Review of manuscript “μ-Λ relationships for convective and stratiform rainfall in the Netherlands” submitted to Atmospheric Measurement Techniques

General Comments

This is an interesting study about convective and stratiform relationships of rain drop size distributions. The interpretation of the mu – gamma relationship parameters is a particularly valid contribution. Overall, I think the manuscript should be published but I recommend complementing some aspects (introduction), reorder (quality control should no be described in the results sections) and fix a few details – please see below.

Specific Comments

1. Page 1, abstract. “In this study, we take a closer look at the important issue of μ-Λ relationships in raindrop size distributions (DSD) by conducting a systematic analysis of twenty months of rainfall data in the Netherlands”. I think the abstract should specify that the main analysis is performed with disdrometer data, as other approaches are possible, for example using horizontal radar reflectivity fields or vertical profiles (see next comment).
2. Page 2, Introduction. As mentioned in the previous comment I recommend to briefly expand the initial part of the introduction with a comment about general approaches to classify convective and stratiform precipitation. Now the first sentence of section 3.3 seems to do this function but I do not think it is complete or well located there. I suggest moving it to the first paragraph of the introduction and comment that other techniques may include radar scanning (polar volumes) radar data or vertical profiles (see for example Qi et al 2013, Powell et al 2016, Ghada et al 2022, Romatschke & Dixon 2022), as well as ground based rain gauge or disdrometer data, as already explained in the paper.
3. Page 3, Data. The text indicates that two co-located Parsivel2 units are used. Could you please briefly comment if the plane of measurements are aligned? At some sites co-located Parsivel units are installed perpendicularly.
4. Page 3, Data. Quality control. I think that an overview of the data quality control should be given either in the Data or Methodology section, and then explain the results in current section 4.1. For example, did author considered some conditions on number of particles present at each 1-min time slot to be considered valid (as in Hachani et al 2017)? Moreover, no mention is made about possible effects of wind on the data (see for example Friedrich et al. 2013, Li et al 2021).
5. Page 3, Data. How was the ZEUS lightning data used? Did authors check if they were present in some specifi time/range window? In page 7, line 138, the 4 item listed does not specify. Please comment briefly in the Data section or in 3.3. section.
6. Page 3, Data. Finally I recommend that the number of data used (total and final valid minutes) is indicated in the Data section.
7. Page 7. As mentioned I suggest to move the description of the QC to the Data section and only, if completely necessary, leave here the results. By the way, note that ‘Parsivel 1 and 2’ are not properly introduced – this can be easily done in section Data, something as ”two co-located Parsivel2 units are used (hereafter Parsivel 1 and Parsivel 2)".
8. Page 17, Figure 4. Should the convective fit line be restricted to the maximum value of the data used for the fitting? Please comment.

Formal

1. Page 2. Please check format of the references (for example page 2, line 34, etc.)
2. Page 8, line 178. I could not find Section III C (why in Roman numbers?) – please correct.
3. Page 9. Equation 9. The format of the lower integration limit given (D=0) is not consistent with Equation 10. Please correct.
4. Page 16, Figure 3. Could you please produced the scatter plots as square figures (not rectangles), i.e. with the same length in the x-axis and the y-axis? This allows an easier visual comparison, particularly when the magnitudes in both axis are the same.

References

Friedrich, K.,  et al. 2013. Articulating and stationary PARSIVEL disdrometer measurements in conditions with strong winds and heavy rainfall. Journal of Atmospheric and Oceanic Technology, 30(9), 2063-2080.

Ghada, W., et al. 2022. Stratiform and Convective Rain Classification Using Machine Learning Models and Micro Rain Radar. Remote Sensing, 14(18), 4563.

Hachani, S., et al. 2017. Drop size distribution climatology in Cévennes-Vivarais region, France. Atmosphere, 8(12), 233.

Lin, L., et al. 2021. Correction to raindrop size distributions measured by PARSIVEL disdrometers in strong winds. Atmospheric Research, 260, 105728.

Powell, S.W., et al. 2016. Rainfall-type categorization of radar echoes using polar coordinate reflectivity data. Journal of Atmospheric and Oceanic Technology, 33(3), 523-538.

Qi, Y., et al. 2013. A real‐time automated convective and stratiform precipitation segregation algorithm in native radar coordinates. Quarterly Journal of the Royal Meteorological Society, 139(677), 2233-2240.

Romatschke, U. and Dixon, M.J., 2022. Vertically resolved convective–stratiform echo-type identification and convectivity retrieval for vertically pointing radars. Journal of Atmospheric and Oceanic Technology, 39(11), 1705-1716.

Please see attached file