Oslo CTM3 Sea Salt (SALT)
The salt application is a stand-alone module, described by Grini et al. (2002). It uses a certain number of size bins (tracers), specified by the user, with diameters ranging logarithmically even-spaced from 0.03μm to 25.0μm. A standard simulation uses 8 bins (tracers). The theoretical background is in general taken from Fitzgerald (1975).
Production and loss terms are calculated, and the integration of the aerosols is calculated using the QSSA method (Hesstvedt et al., 1978).
Emissions
The surface emissions are driven by the model winds.
Deposition
Sea salt aerosols are falling by gravitational settling, and act as
sources in the layers they fall into.
Wet scavenging
All sea salt aerosols are subject to the Oslo CTM3 wet
scavenging.
Fitzgerald J. W.: Approximation formula for the equilibrium size of an aerosol particle as a function of its dry size and composition and the ambient relative humidity. J. Appl. Meteor., 14, pp 1044-1049, doi:10.1175/1520-0450(1975)014<1044:AFFTES>2.0.CO;2, 1975.
Grini, Alf, Gunnar Myhre, Jostein K. Sundet, and Ivar S. A. Isaksen: Modeling the Annual Cycle of Sea Salt in the Global 3D Model Oslo CTM2: Concentrations, Fluxes, and Radiative Impact, Journal of Climate, Vol. 15, No. 13, pp 1717-1730, doi:10.1175/1520-0442(2002)015<1717:MTACOS>2.0.CO;2, 2002.
Hesstvedt, E., Ø. Hov, and I. S. A. Isaksen: Quasi steady-state approximation in air pollution modelling: Comparison of two numerical schemes for oxidant prediction, Int. Journal of Chem. Kinetics, X, 971-994, doi:10.1002/kin.550100907, 1978.