Chapter 63
On the Importance of Organic Mass
for Global Cloud Condensation Nuclei
Distributions
Georgios Fanourgakis, Nikos Kalivitis, Athanasios Nenes
and Maria Kanakidou
Abstract Aerosol-cloud interactions constitute a major contributor of uncertainty
in projections of anthropogenic climate change. The fraction of aerosol that activates
to form cloud droplets (cloud condensation nuclei, CCN) is at the heart of aerosol
cloud interactions. Towards this, we investigate the role of organic mass in the formation and evolution of CCN using the global 3-dimensional chemistry transport model
TM4-ECPL coupled with the M7 aerosol microphysics module. The contribution of
organics to the CCN levels is quantified by comparing the global surface distribution of aerosol particles and CCN computed with and without organic aerosol mass
considerations, to the surface CCN observations. We also calculate the dynamical
behavior of the CCN by computing their persistence times in atmosphere, i.e. the
period over which the CCN concentrations show autocorrelation. It is found that
organic species in aerosol modulate CCN concentrations by 50–90%—with a higher
influence over land; furthermore, simulations compare better with observations when
the impact of organics on CCN levels is taken into account.
G. Fanourgakis · N. Kalivitis · M. Kanakidou (B)
Environmental Chemical Processes Laboratory, Department of Chemistry, University of Crete,
Heraklion, Greece
e-mail: mariak@uoc.gr
G. Fanourgakis
e-mail: fanourg@uoc.gr
N. Kalivitis
National Observatory of Athens, P. Penteli 15236, Athens, Greece
e-mail: nkalivitis@uoc.gr
A. Nenes
Laboratory of Atmospheric Processes and their Impacts, School of Architecture, Civil &
Environmental Engineering, École Polytechnique Federale de Lausanne, Lausanne 1015,
Switzerland
e-mail: athanasios.nenes@epfl.ch
Institute of Chemical Engineering Sciences, Foundation for Research and Technology
(ICEHT-FORTH), Hellas, Patras 26504, Greece
© Springer Nature Switzerland AG 2020
C. Mensink et al. (eds.), Air Pollution Modeling and its Application XXVI,
Springer Proceedings in Complexity,
https://doi.org/10.1007/978-3-030-22055-6_63
395
On the Importance of Organic Mass
for Global Cloud Condensation Nuclei
Distributions
Georgios Fanourgakis, Nikos Kalivitis, Athanasios Nenes
and Maria Kanakidou
Abstract Aerosol-cloud interactions constitute a major contributor of uncertainty
in projections of anthropogenic climate change. The fraction of aerosol that activates
to form cloud droplets (cloud condensation nuclei, CCN) is at the heart of aerosol
cloud interactions. Towards this, we investigate the role of organic mass in the formation and evolution of CCN using the global 3-dimensional chemistry transport model
TM4-ECPL coupled with the M7 aerosol microphysics module. The contribution of
organics to the CCN levels is quantified by comparing the global surface distribution of aerosol particles and CCN computed with and without organic aerosol mass
considerations, to the surface CCN observations. We also calculate the dynamical
behavior of the CCN by computing their persistence times in atmosphere, i.e. the
period over which the CCN concentrations show autocorrelation. It is found that
organic species in aerosol modulate CCN concentrations by 50–90%—with a higher
influence over land; furthermore, simulations compare better with observations when
the impact of organics on CCN levels is taken into account.
G. Fanourgakis · N. Kalivitis · M. Kanakidou (B)
Environmental Chemical Processes Laboratory, Department of Chemistry, University of Crete,
Heraklion, Greece
e-mail: mariak@uoc.gr
G. Fanourgakis
e-mail: fanourg@uoc.gr
N. Kalivitis
National Observatory of Athens, P. Penteli 15236, Athens, Greece
e-mail: nkalivitis@uoc.gr
A. Nenes
Laboratory of Atmospheric Processes and their Impacts, School of Architecture, Civil &
Environmental Engineering, École Polytechnique Federale de Lausanne, Lausanne 1015,
Switzerland
e-mail: athanasios.nenes@epfl.ch
Institute of Chemical Engineering Sciences, Foundation for Research and Technology
(ICEHT-FORTH), Hellas, Patras 26504, Greece
© Springer Nature Switzerland AG 2020
C. Mensink et al. (eds.), Air Pollution Modeling and its Application XXVI,
Springer Proceedings in Complexity,
https://doi.org/10.1007/978-3-030-22055-6_63
395