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\subsection{Theoretical approaches}  Bubbles encapsulate water vapors and other gases. We are interested in analyzing bubbles, because, as mentioned, bubbles are a direct cause for transfer velocity of different gases. Aerosols are produced as sea spray particles by the breaking of the surface tension of individual bubbles. The bubble film layers are fragmentated into small droplets (film droplets). Bubbles usually cary salt and organic particles so they are called "dirty" bubbles. The more "loaded" bubbles are, the more effective they are in generating cloud condensation nucleis. The difficulty is that loaded bubbles have a higher dragging effect, which comes with a decrease in vertical velocity (upward motion) of the bubbles. Coarser salt or organic particles carried by bubbles have a higher inertia, so the "popping" momentum in launching aerosols into the atmospheric boundary layer is inhibited.  Molecular diffusion for subsurface bubbles is an important feature for gas transfer, because it actually gas transfer. The higher the molecular diffusion through bubble walls, the less available the number of bubbles at the surface which can organize in foam patches. If the foam patches contain gases with low solubility, they become void fractions. There is a relation between void fractions and interstitial water, which involves the transfer velocity. For highly insoluble gases, the capacity of the interstitial water may be smaller than that of the bubble even for small void fractions \cite{en_Liddicoat_Baker_et_al__2007}. This is called restriction of gas transfer in a dense isolated plume "suffocation". High subsurface bubbles molecular diffusion inhibits the buoyancy of bubbles and, hence, the vertical upward velocity of bubbles. In this sense, the Wolf model shows that there is a higher gas transfer for low Schmidt number, $Sc$, therefore subsurface lower molecular diffusion, $D$, generates more gas available at the surface, hence a higher transfer rate. Low Schmidt number means higher upward vertical velocity for subsurface bubbles, therefore more available bubbles for surfacing. Wolf model assumes two cases for the transfer velocity: one without void fraction and the other with 20 % void fraction  In order to obtain the whitecap fraction, one can refer to an average bubble persistence time $\tau_{bub}$ to obtain $W$:  \begin{equation}  W = \int_{0}^{\infty}\tau _{bub}c\Lambda (c)dc