Gschwend%20thesis.pdf

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but that direct inputs (e.g. from boating activities) dominate. However,
even at this time, the atmosphere may operate as a buffer and .act as a
sink until the return of concentrations to background levels after summer
weekends. A brief calculation, utilizing the stagnant boundary layer model
of the air-sea interface (Broecker and Peng, 1974; Liss and Slater, 1974)
can show that exchange to the atmosphere may diminish a suddenly increased
concentration of a volatile compound in seawater to less than 20% of the
size of the spike within a week:
.dC D A
flux after spike input = dt =- _ -; x V (Cexcess)
where C = concentration of the organic compound,
t = time
D = diffusion coefficient
z = stagnant boundary layer thickness
A = cross sectional area of diffusion
v = volume of water column under A
C = spike concentration over and above concentration in
excess
equilibrium
rearranging and integrating
for the region of CD,
ln C/C o
C
DA
= -- x t
zV
= C exp C DA x t)
o zV
D = 0.6 x 10-5 cm2/sec based on diffusion coefficient of methane and the
proportion of the square roots of molecular weights
(Witherspoon and Bonoli, 1969; Liss and Slater, 1974).