Chapter 62
Sea Spray Effects on Marine and Coastal
Boundary Layer
George Kallos, C. Stathopoulos, P. Patlakas, G. Galanis, J. Al Qahtani
and I. Alexiou
Abstract The air-water exchange processes are considered as complicated but very
important for the boundary layer structure. The complex physical procedures related
to momentum, moisture and thermal exchanges, render their numerical description
into a quite challenging task. Ocean surface roughness and spray droplets have an
impact on the lower atmospheric layers with profound effects. These involve alterations in the atmospheric stability profiles and microphysical processes such as the
formation of sea salt particles. Water vapor produced by sea spray can alter humidity and temperature profiles close to the ocean surface, leading to modified stability
conditions. This cascade of effects can be further extended to wind profiles. Sea
salt particles derived from water droplet evaporation are a major source of CCN and
GCCN that may lead in low cloud formation over the sea and/or the coastal boundary
layer. To describe these processes numerically, an atmospheric-wave-spray coupled
system is introduced. The RAMS/ICLAMS atmospheric and the WAM wave spectral
model are interfaced, including schemes for ocean drag, water droplet thermodynamics and salt particles considered as predictive quantity. Model simulations performed
in the Atlantic shoreline showed that droplet evaporation near the surface modifies
the atmospheric stability and affects sea salt dispersion.
62.1 Introduction
In the air-sea interface zone, mechanical processes entail the transfer of momentum
from the atmosphere to the ocean through the imposed drag of wind leading to wave
generation. Likewise, a wave stress emerges, which is encountered by the surface
G. Kallos (B) · C. Stathopoulos · P. Patlakas · G. Galanis
Department of Physics, National and Kapodistrian University of Athens, Athens, Greece
e-mail: kallos@mg.uoa.gr; g-kallos@otenet.gr
G. Galanis
Naval Academy of Greece, Section of Mathematics, Piraeus, Greece
J. Al Qahtani · I. Alexiou
Saudi Aramco, Dhahran, Saudi Arabia
© 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_62
389
Sea Spray Effects on Marine and Coastal
Boundary Layer
George Kallos, C. Stathopoulos, P. Patlakas, G. Galanis, J. Al Qahtani
and I. Alexiou
Abstract The air-water exchange processes are considered as complicated but very
important for the boundary layer structure. The complex physical procedures related
to momentum, moisture and thermal exchanges, render their numerical description
into a quite challenging task. Ocean surface roughness and spray droplets have an
impact on the lower atmospheric layers with profound effects. These involve alterations in the atmospheric stability profiles and microphysical processes such as the
formation of sea salt particles. Water vapor produced by sea spray can alter humidity and temperature profiles close to the ocean surface, leading to modified stability
conditions. This cascade of effects can be further extended to wind profiles. Sea
salt particles derived from water droplet evaporation are a major source of CCN and
GCCN that may lead in low cloud formation over the sea and/or the coastal boundary
layer. To describe these processes numerically, an atmospheric-wave-spray coupled
system is introduced. The RAMS/ICLAMS atmospheric and the WAM wave spectral
model are interfaced, including schemes for ocean drag, water droplet thermodynamics and salt particles considered as predictive quantity. Model simulations performed
in the Atlantic shoreline showed that droplet evaporation near the surface modifies
the atmospheric stability and affects sea salt dispersion.
62.1 Introduction
In the air-sea interface zone, mechanical processes entail the transfer of momentum
from the atmosphere to the ocean through the imposed drag of wind leading to wave
generation. Likewise, a wave stress emerges, which is encountered by the surface
G. Kallos (B) · C. Stathopoulos · P. Patlakas · G. Galanis
Department of Physics, National and Kapodistrian University of Athens, Athens, Greece
e-mail: kallos@mg.uoa.gr; g-kallos@otenet.gr
G. Galanis
Naval Academy of Greece, Section of Mathematics, Piraeus, Greece
J. Al Qahtani · I. Alexiou
Saudi Aramco, Dhahran, Saudi Arabia
© 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_62
389