308
C. Hogrefe et al.
ulations over Europe were excluded from this plot since their values were a factor
of 10 higher than the maximum AQMEII2 model displayed (AQ2-EU1). Given the
importance of ozone dry deposition for model performance [9], future work needs
to be directed at understanding the drivers for these model differences at the process
level, following step-wise approaches such as those employed in Schwede et al. [6].
Table 48.2 provides a comparison of observed and modeled annual wet deposition.
Based on the comparison of the median model results and observations, there is a tendency to underestimate SO 4
2− , NO 3
− , and NH 4
+ wet deposition over both continents
in 2006 and 2010. However, the range of simulated deposition values across models
is substantial, varying between species, years, and AQMEII phases from a factor of
2 to a factor of 20. The range of variability is consistent with the AQMEII1 modelto-model analysis presented in Solazzo et al. [8] and highlights that—besides better
understanding process drivers for these differences—future work is also needed for
developing and applying formal criteria to construct deposition ensembles for impact
assessments, refining ad hoc criteria used in earlier studies [11, 13]. It is envisioned
that future AQMEII work could contribute to efforts to construct regional and global
maps of total deposition based on fusing measurements and model simulations [7,
11, 14].
Acknowledgements and Disclaimer We gratefully acknowledge NADP for providing wet deposition measurements over the U.S. (http://nadp.slh.wisc.edu/) and NILU for providing EMEP wet
deposition measurements over Europe through EBAS (http://ebas.nilu.no/). The views expressed
in this article are those of the authors and do not necessarily represent the views or policies of the
U.S. Environmental Protection Agency.
References
1. G.R. Carmichael et al., Atmos. Env. 36, 175–199 (2002). https://doi.org/10.1016/S13522310(01)00448-4
2. F. Dentener et al., Glob. Biogeochem. Cycl., 20, GB4003 (2006). https://doi.org/10.1029/
2005gb002672
3. S. Galmarini, S. T. Rao, Atmos. Env., 45 (2011). https://doi.org/10.1016/j.atmosenv.2011.03.
025
4. S. Galmarini et al., Atmos. Env., 115 (2015). https://doi.org/10.1016/j.atmosenv.2015.06.009
5. S. Galmarini et al., Atmos. Chem. Phys. 17, 1543–1555 (2017). https://doi.org/10.5194/acp17-1543-2017
6. D.B. Schwede et al., Atmos. Env., 45 (2011). https://doi.org/10.1016/j.atmosenv.2010.11.050
7. D.B. Schwede, G.G. Lear, Atmos. Env. (2014). https://doi.org/10.1016/j.atmosenv.2014.04.
008
8. Solazzo et al., Atmos. Env., 53 (2012), https://doi.org/10.1016/j.atmosenv.2012.02.045
9. E. Solazzo et al., Atmos. Chem. Phys. 17, 10435–10465 (2017). https://doi.org/10.5194/acp17-10435-2017
10. J. Tan et al., Atmos. Chem. Phys. 18, 6847–6866 (2018). https://doi.org/10.5194/acp-18-68472018
11. R. Vet et al., Atmos. Env., 93 (2014). https://doi.org/10.1016/j.atmosenv.2013.10.060
12. M.G. Vivanco et al., Atmos. Env., 151 (2017). https://doi.org/10.1016/j.atmosenv.2016.11.042
13. M.G. Vivanco et al., Atmos. Chem. Phys. 18, 10199–10218 (2018). https://doi.org/10.5194/
acp-18-10199-2018
14. WMO, WMO Report #234, S. Carou and R. Vet, World Meteorological Organization, Geneva,
Switzerland (2017)
C. Hogrefe et al.
ulations over Europe were excluded from this plot since their values were a factor
of 10 higher than the maximum AQMEII2 model displayed (AQ2-EU1). Given the
importance of ozone dry deposition for model performance [9], future work needs
to be directed at understanding the drivers for these model differences at the process
level, following step-wise approaches such as those employed in Schwede et al. [6].
Table 48.2 provides a comparison of observed and modeled annual wet deposition.
Based on the comparison of the median model results and observations, there is a tendency to underestimate SO 4
2− , NO 3
− , and NH 4
+ wet deposition over both continents
in 2006 and 2010. However, the range of simulated deposition values across models
is substantial, varying between species, years, and AQMEII phases from a factor of
2 to a factor of 20. The range of variability is consistent with the AQMEII1 modelto-model analysis presented in Solazzo et al. [8] and highlights that—besides better
understanding process drivers for these differences—future work is also needed for
developing and applying formal criteria to construct deposition ensembles for impact
assessments, refining ad hoc criteria used in earlier studies [11, 13]. It is envisioned
that future AQMEII work could contribute to efforts to construct regional and global
maps of total deposition based on fusing measurements and model simulations [7,
11, 14].
Acknowledgements and Disclaimer We gratefully acknowledge NADP for providing wet deposition measurements over the U.S. (http://nadp.slh.wisc.edu/) and NILU for providing EMEP wet
deposition measurements over Europe through EBAS (http://ebas.nilu.no/). The views expressed
in this article are those of the authors and do not necessarily represent the views or policies of the
U.S. Environmental Protection Agency.
References
1. G.R. Carmichael et al., Atmos. Env. 36, 175–199 (2002). https://doi.org/10.1016/S13522310(01)00448-4
2. F. Dentener et al., Glob. Biogeochem. Cycl., 20, GB4003 (2006). https://doi.org/10.1029/
2005gb002672
3. S. Galmarini, S. T. Rao, Atmos. Env., 45 (2011). https://doi.org/10.1016/j.atmosenv.2011.03.
025
4. S. Galmarini et al., Atmos. Env., 115 (2015). https://doi.org/10.1016/j.atmosenv.2015.06.009
5. S. Galmarini et al., Atmos. Chem. Phys. 17, 1543–1555 (2017). https://doi.org/10.5194/acp17-1543-2017
6. D.B. Schwede et al., Atmos. Env., 45 (2011). https://doi.org/10.1016/j.atmosenv.2010.11.050
7. D.B. Schwede, G.G. Lear, Atmos. Env. (2014). https://doi.org/10.1016/j.atmosenv.2014.04.
008
8. Solazzo et al., Atmos. Env., 53 (2012), https://doi.org/10.1016/j.atmosenv.2012.02.045
9. E. Solazzo et al., Atmos. Chem. Phys. 17, 10435–10465 (2017). https://doi.org/10.5194/acp17-10435-2017
10. J. Tan et al., Atmos. Chem. Phys. 18, 6847–6866 (2018). https://doi.org/10.5194/acp-18-68472018
11. R. Vet et al., Atmos. Env., 93 (2014). https://doi.org/10.1016/j.atmosenv.2013.10.060
12. M.G. Vivanco et al., Atmos. Env., 151 (2017). https://doi.org/10.1016/j.atmosenv.2016.11.042
13. M.G. Vivanco et al., Atmos. Chem. Phys. 18, 10199–10218 (2018). https://doi.org/10.5194/
acp-18-10199-2018
14. WMO, WMO Report #234, S. Carou and R. Vet, World Meteorological Organization, Geneva,
Switzerland (2017)