I thank the authors for their point to point reply to the reviewers comments. The replies clarified significantly the procedure used for the global estimates provided. However, I consider that additional improvements are needed after which the paper can be published in ACP.
1- The authors now clarified that the MODIS cloud cover data are taken from the work of King et al 2013 – they precisely provide Figure 2b from that paper and R-1 in the replies. Thus I understand that the authors did not use the digital form of the data, since they do not provide a figure drawn by themselves. I also understand from their response that this figure is used to visually make the correspondence with the ecosystem map again taken from a publication in Burrows et al 2009b – here also no digital data seem to be used (figure R-2 provided in the replies). If this is the case, it has to be clearly stated. In such case, I also wonder how the mean cloud fraction over each ecosystem type that is provided in Table 2 is derived. For instance, forests over S America, where rainforests exist, based on these figures, are seen to correspond to cloud over of almost 1.0, while in Indonesia values as low as 0.4 can be seen from the figures. The methodology has to be clearly articulated in section 2.4.2. This section has been improved in clarity but does not state 1) that the correspondence between cloud fraction and ecosystems was done visually and 2) how the mean over the same ecosystem type with different cloud fractions is made. Furthermore, I consider that an estimate of the uncertainty in the numbers provided in Table 2 should be also provided.
2- ‘Reasonable estimate’ of cloudiness (line 197) is a vague statement. How much uncertainty tolerates ‘reasonable’?
3- Table 2 caption: MODIS cloud cover data from King et al (2013). Is it annual mean data as written in the caption or spring time as explained in the text?
4- Ecosystem category ‘Seas’ you mention that sea-ice is not included in this category, however from Figure R-2 we can see that ‘Seas’ cover also the North Pole region which is expected to have sea-ice. Therefore Sea-ice area seems to be included in the ecosystems as seas without differentiation. Please check again and revised lines 236-237 accordingly.
5- Section 3.1.3. Although the flow of discussion has been improved, I still do not understand why for instance the authors discuss fungal spores and not pollen also, which is a large fraction of bioaerosols mass in the atmosphere.
6- Line 377 please provide reference.
7- The authors want to make the difference between WSOC and aqSOA. However this distinction is not explained in the manuscript. I suggest that a sentence or two are added early in the document to explain to what WSOC and aqSOA differ according to the authors.
8- Line 421 replace year-1 by yr-1
9- Because WSOC is used for bacteria growth, it is not clear how much overall the aqSOA could change during bacteria growth and multiplications. However, bacteria may ‘fix’ very light organics, which are mainly dissolved in the water phase from the gas phase in the atmosphere, to the aqSOA, i.e. in forms that remain in the aerosol phase after evaporation. Thus I think the provided first estimate of SBA could be seen as an upper limit of impact on aqSOA.
10- Table 4, the provided range of Fc is 0.2 to less than 1 and not 0.8 as stated in the reply to the reviewer 3 comments. Please check maximum value. Also it would be nice to provide in the text a range of the estimate (or a % uncertainty) based on the min/max of all the parameters provided in Table 4. How such range will affect the conclusions of the manuscript?

I would like to thank the authors for the clarity provided during the revision of their manuscript and further ask a few extra corrections/improvements before this is published in ACP.
1- In your reply to my earlier comment 1 you have added in page 8, lines 19-22:
“This visual approach to derive cloud fractions from the average maps neglects details on the variability of cloud fractions among the same ecosystem category in different geographic regions. For such categories (e.g. forests), we estimated a single average value based on the surface-weighted fractions of the different regions.”
How you can use ‘visual approach’ and also calculate ‘surface-weighted fractions’? Some rephrasing is here needed.
2- Page 14, lines 10-18 do not read well any more. To address my comment 5 you have added discussion in lines 10-14 that is now disconnected from what follows leading also to repetitions. I suggest you add all emission estimates for fungal spores (with appropriate discussion and references) together in line 11 and remove lines 15-18. Then start line 19 by: ‘In addition none of the above mentioned fungal spore emission estimates includes…’
3- Page 19,line 2: ‘into the same difference’ do you mean ‘into a proportional change’?
After these small last improvements, the manuscript can be published in ACP. Thank you very much for choosing ACP for the publication of your research results. Maria Kanakidou