Interactive comment on “Observation- and Model-Based Estimates of Particulate Dry Nitrogen Deposition to the Oceans” by Alex R. Baker et al

The first paragraph should be shortened as much as possible to indicate the importance of model-observation comparisons as well as the influence of mineral dust on N depositions. The methodology in the second paragraph is much hard to follow: why choose TM4? How about the two commonly applied methods to calculate N deposition fluxes for CalDep? Does CalDep have the results of deposition fluxes of NOy and NHx? Are NOy and NHx derived from wet and dry depositions? Is it possible to compare nitrate and ammonium with ACCMIP means? In addition, is it possible to separate the contributions of deposition velocities and N concentration to modelobservation discrepancy? I believe that it is much importance for scientific community to improve the model-related works in the future. Introduction: Line 71-73: A few of global atmos. Models has been applied for large scale assessment of N deposition over oceans, such as Dentener et al. (2006), Wang et al. (2015), etc. such works should be cited: Dentener, F., Drevet, J., Lamarque, J. F., Bey, I., Eickhout, B., & Fiore, A. M., et al. (2006). Nitrogen and sulfur deposition on regional and global scales: a multimodel evaluation. Global Biogeochemical Cycles, 20(4), 16615-16615; Wang, R., Balkanski, Y., Bopp, L., Aumont, O., Boucher, O., & Ciais, P., et al. (2015). Influence of anthropogenic aerosol deposition on the relationship between oceanic productivity and warming. Geophysical Research Letters, 42(24), 10745-10754. Lin 88-89: again, please explain why choose TM4 in this study Lin 105-108: Sampling biases due to multiple sources should be discussed in details. Is any type of samples excluded based on sampling regulation related to N deposition in this study? It is better to describe the sampling regulation (sampler, period, temporal resolution, size fractions, sampling method, analytical method, etc) in main text or SI file or the dataset SOLAS Methods: Line 127: Explain the abbreviation ECMWF first, and justify why choose ECMWF. Actually a few of reanalysis datasets including surface wind speed could be C2