In this study, the authors develop a method to quantify the contribution of ARs, cyclones, and fronts to precipitation rate over the Atlantic sector of Arctic based on ERA5. They focus on two distinct periods from two airborne campaigns: ACLOUD and AFLUX. They found that the contribution of these weather systems to the precipitation rate differ substantially between these two periods. In particular, the precipitation rate during ACLOUD is mostly associated with AR- and front-related components while cyclone-related component dominates the precipitation rate during AFLUX. The contributions of different weather systems to precipitation phase (snow versus rain) and formation mechanism (large-scale versus convective) are also explored. Lastly, the authors also test the sensitivity of the results presented here to the AR and cyclone detection algorithms and whether a precipitation threshold is applied.

Overall, the manuscript is well written. The method developed in this study provides a new perspective on how different weather systems contribute to precipitation over Arctic. My main concern is that the authors seem to make the assumption that the different contribution by weather systems between the two studied periods arise mainly from seasonality. In my opinion, this assumption cannot be justified by the current study. I will elaborate more on my concerns in the specific comments listed below. This manuscript has the potential to be published in ACP if the concerns listed below can be properly addressed.

Specific Comments:

1. Throughout the manuscript, the authors seem to implicitly assume that the difference between the two study periods are due to seasonality. For example, in lines 276, 302 and 366, the authors use the term “seasonal differences”. However, the results presented here based only on two short periods: one is 14 days and another one is 19 days. Until further study based on the full ERA5 record is conducted, I would not recommend the authors attributing the differences between two study period to seasonal differences.
2. Line 96: To me, the cyclone seems to locate in the Northeastern or Eastern Greenland.
3. Line 126-127: The authors should double-check the Guan & Waliser (2015) paper. I don’t think they set the lower limit of the IVT threshold to 50 kg/m/s in the polar regions.
4. Line 184-186: “The effect is roughly 20 % of the residual and is slightly larger in absolute terms during 185 ACLOUD (about 8 % of the total precipitation) compared to AFLUX (about 5 %) as residual precipitation is more frequent during ACLOUD.” This sentence needs to be rewritten for better clarity. I am not sure what the authors are trying to convey here.
5. Line 269-274. More explanations for the hypothesis are needed. The two points followed the first sentence in this paragraph are simply describing the difference between the two periods. They are not explanations for the hypothesis.
6. Line 289: How do you weigh precipitation rates by the area? To me, you just simply sum up the precipitation rates across all the grid points over the study region.
7. Table 1 caption: For the daily averaged precipitation rate, did you calculate it simply by summing up the precipitation rates across all grid points over the study region?
8. Line 304: In my opinion, meridionally oriented ARs over the Arctic should be more effective in inducing precipitation. Meridionally oriented ARs over the Arctic travel across a strong temperature gradient from warmer regions to colder regions. Cold air holds less moisture. The moisture inside the ARs thus have to precipitate out. That is to say, for a given AR and a given season, the AR would induce stronger precipitation when it orients meridionally compared to when it orients zonally.
9. Line 347: “For rain, the fraction of total precipitation is highest for ACLOUD with 33% and lower for AFLUX with 10%.” This sentence needs to be rewritten for better clarity.
10. Line 367: Based on Figure 8b, rain occurs during AFLUX.
11. Line 383: I would not use “underestimate” here. We don’t know which AR detection algorithms represent the truth.
12. Line 385-386: I couldn’t find these 8% and 6% in Table 1.
13. Line 390: “Consequently, …” I don’t see how previous sentences can lead to this conclusion. More explanations are needed.
14. Line 445-454: Any potential explanations for why AR_GU detects larger ARs for ACLOUD, but smaller ARs for AFLUX, and why CYC_A detects larger cyclones during ACLOU, but smaller cyclones during AFLUX?
15. Line 50: regions’ hydroclimate?
16. Line 384: Do you mean GuS produced the strong precipitation contribution by cyclones?
17. Line 435: Do you mean ACLOUD?

See the attachment