Thank you very much for the careful revision of your manuscript. However, further improvements are needed before being accepted for publication in ACP. In addition the use of English language has to be checked throughout the text. Please perform these changes and resubmit your manuscript as a track changes document.

Line 29-30: ‘have a serious impact’ replace by ‘ significantly impact’
Lines 193-194: What was the origin of these air masses?
Line 236: The chemical reaction of anydrosugars with OH radicals…
Line 249: ‘ under different variables’ what do you mean?
Line 252: induced by photochemical aging via oxidation by OH radicals
Line 255 remove ‘were’
Line 256: ‘to contribute’ do you mean ‘ to explain’
Line 260:Wet deposition may be another cause .
Line 354: remove ‘were’
Line 392: They are released into the atmosphere…
Line 408-409: in which sugar alcohols contributed more to the total sugars (ave. 54.2%) than primary sugars (ave. 25.8%) in Alaskan aerosols
Line 422: as major sources
Line 435: the same sample showed
Line 449 replace ‘implication’ by ‘finding’
Line 454: mannitol concentrations were higher during …
Line 461: contributes
Line 483: is also produced…
Line 564: that can be further…
Line 643: replace ‘SOA tracers that contribute very less to …’
SOA tracers with minor contribution
Line 648: replace ‘portion’ by ‘fraction’
Line 659: burning of softwood is common source
Lines 674 to 686 belong to the introduction and not here, please move appropriately
Lines 679: replace ‘were more than double’ by ‘’more than doubled’
Table 2: the 3rd column with the P values is not needed because the necessary information is already in column 4..

Thank you for the careful revision of your manuscript. This can be now published in ACP.
kind regards, Maria Kanakidou