This paper has been reviewed by two experts in the field and both agree that the paper reports significant results. It addresses an important gap in the understanding of HO reactivity associated with BVOC emission especially in Boreal, and the difficulties in addressing this issue. But both reviewers provide a wide range of significant and useful comments, and pointed out some errors, all of which should first be addressed. I find the paper suitable for publication in BG and concur with the reviewers support of its ultimate publication after appropriate revisions.

The authors now outlined a detail response that seems to adequately address all the reviewers comments and are therefore invited to submit a fully revised version for re-evaluation. I would only note that the authors should avoid as much as possible leaving responses in the response letter without actual corresponding changes in the revised paper.

This paper received supporting views by two expert referees in the first cycle, but also extensive comments and suggesting for revisions. As proposed by the authors, and implemented in the revised version the comments were satisfactorily addressed. This is now confirmed by two reviewers and I concur. The new referee in this cycle has two additional comments that seems useful, including clarifications and improved statistics on the key finding. I recommend to addressed these additional points in minor revisions before final acceptance for publication in BG.

The authors have addressed the remaining comments of the reviewers and altogether the paper is now fully revised and I am happy to recommend its final publication in BG.