The paper provides a comprehensive overview of the NOx and VOCs sources in sub-Saharan Africa. It is well written and has a clear outline.

There is a large increase in isoprene for region 1 and region 3 in the northern hemisphere during the dry season, peaking in March for SVOC, STD and ALBE inversions.  At this time and location, the HCHO columns are quite high (figure 10), and this coincide with the peak in fire emissions, which must explain part of increase in isoprene. At the same, these inversions do not capture the increase in isoprene  during fall in region 1.

While the precise source attribution will not be solved in this study, you could still provide some context at whether why the isoprene columns are not well represented in both the prior simulations and inversions and provide some hypothesis(es) to guide future studies. A figure of the seasonal cycle of NOx and VOCs surface emissions by source (anthropogenic, biogenic and pyrogenic) for both the prior and the STD inversions (having the other inversions might make the plot too busy) could illustrate this issue.

Even though the increments on anthropogenic emissions are not large, it would be appreciated to add a key point about main takeaways on this subject in the conclusion section.

Minor comments:

L47: “Global bottom-up inventories for soil and lightning fluxes range from 1.3 to 6.6 TgN yr-1 (Murray, 2016; Vinken et al., 2014; Weng et al., 2020), and from 4 to 34 TgN yr-1 (Steinkamp and Lawrence, 2011; Yan et al., 2005), respectively”

You switched up soil and lightning.

L60: remove the parenthesis after “Lebel et al., 2011);”

L63: “By virtue of their global coverage and continuous monitoring, spaceborne data are great alternatives to studying air composition in Africa and are often used to constrain model emission estimates obtained with chemistry-transport models (CTMs).” At this stage of the discussion, you could say: can be used to constrain instead of are often.

L98: first definition of TROPOMI and S5P acronyms, so no need to redefine them at line 177.

L101: first instance of MAGRITTE, please define the acronym here.

L105: make it 3 sentences for section 2, 3 and 4. Please be consistent and choose either Sect. or Section.

2.1 MAGRITTEv1.1 chemistry-transport model

If you are using a limited area version of the model, you should specify how you prescribed the boundary conditions.

The authors conducted adjoint-based inverse modelling to update emissions of NOx and VOC over Africa for 2019 using a chemistry-transport model MAGRITTEv1.1 and TROPOMI HCHO and NO2 retrievals. This is a robust study. Even though there are uncertainties associated with assumptions and methods in the approach, the authors conduct additional analyses (an ensemble of inversions) to evaluate and address these uncertainties. The updated emissions have also been evaluated using available observations. This study is important and informative given limited knowledge and observations of Africa NOx and VOC emissions. The manuscript is well written. I have no major concerns or comments on this manuscript. Below are only a few minor suggestions.

Please consider adding latitude and longitude to your map plots. For example, Line 393 says “decreases in soil emissions in the Northern Hemisphere”. Without latitude and longitude, it’s hard to visualize in Figure 11.

Caption of Figure 17: Please change “Histogram of average soil NO flux measurements” to “Average soil NO flux”.

I wonder if the author could add more discussion on the implication on MEGAN.