Overall, the reviews and revisions were good and I find this manuscript acceptable for publication. The revised text has some small issues that should be resolved before publication.

page 1, line 9. The sentence "Analysis of the relations among aerosol, NO2 and HCHO shows higher aerosol to HCHO ratios in winter indicating a longer atmospheric lifetime of aerosol and HCHO." is a bit confusing. The ratio of aerosol to HCHO is mentioned but then both aerosol and HCHO are said to have a longer lifetime. I think that page 15, lines 12-14 really argue that the larger ratio of aerosol / HCHO in winter is a result of longer HCHO lifetime in winter than summer. Please clarify this with respect to the manuscript's arguments.

page 11, Figure 3 panels c and d are a bit incongruous with the text because that text says that HCHO is homogeneous, but panel d looks like there is significant structure. Please change panels c and d to have the lower limit be zero. I would also note that the panel c has a different scale than panel a in the caption. I would also change the end of the caption to say "...taken from Google maps (https://www.google.com/maps/)." -- capitalizing the company "Google" and making maps plural.

page 12, line 5, say "... better horizontal mixing of NO2..." because the shallower layer is caused by less vertical mixing of NO2.