General

This is an interesting study of the variation of cloud and aerosol properties over the northwest Atlantic region using observations during the ACTIVATE campaign. By carefully selecting aircraft measurements in specific flight patterns, this manuscript reports different aerosol and cloud properties in environments with different boundary strengths. The manuscript is well-written, and I do not have major concerns about the reported results. I have the following comments for the authors to consider.

Major

While it is clear how the cloud and aerosol properties differ under different boundary layer conditions, the motivation of this work is not well conceived. I agree that having multiple categories to describe boundary layer coupling strength is important, but how do the proposed categorization and the reported results help the modeling community? Instead of more categories (mainly the moderate coupled categories) and a name is ‘weakly coupled’ rather than ‘decoupled’ boundary layer, what are the new findings from the boundary layer coupling strength analysis in this work? Or is it to confirm some of the previous findings in other regions that are also true in the northwest Atlantic?

Minor

L106: what do you mean by ‘more similar values for aerosol properties in the sub-cloud layer’? Are you referring to, for example, the aerosol numbers and compositions are similar among coupled cases?

L106-108: Please clarify if the statements in the list are from previous studies and preferably include references for each statement. I am curious about what the third statement means. Higher cloud droplet number concentration compared to where or what? Compare to less coupled cases?

L150-153: It took me a while to figure out how the data was analyzed. Can you mark the portion of the legs where the data is used in Figure 1?

L155: do you restrict how far away (or how many seconds apart) the two adjacent MinAlt-BCB legs are?

L156: can you clarify, in the case of slants, if the data are taken from around the BCB leg or the red star in Figure 1? I assume it is the former, but I’m not sure.

L219: How do you determine the threshold for ? Is it based on visual observations of the coupling state and statistics of all the profiles collected during ACTIVATE? Does the distance between BCB and the actual cloud base height affect the threshold selection?

Figure 2: I understand this is a typical case, but do most weakly coupled cases have BCB legs around the middle of the cloud-base height?                                   

L338-340: this is related to the question on the height of CBC leg altitude. Suppose it is the case that the CBC usually sits around half of the cloud-base height. In that case, you are calculating vertical velocity variance at different levels of the boundary layer for the weakly coupled cases than for the other three categories.

L351-352: here, the giant particles refer to aerosol particles, right?