The Langevin non-linear equation is used for describing the tracer position ( Gardiner, 1985 and Kloeden and Platen, 1999): equation(2) dx→tdt=A→x→t+Bx→tξ→t, where A→x→t represents the vector of the deterministic part

of the flow field (transport by the Mike 3 current field). The second term is a stochastic or diffusion term consisting of the tensor Bx→t, characterizing random motion, and the random number vector ξ→t with values between 0 and 1. Equation (1) is equivalent to the stochastic differential equation: equation(3) Compound Library price dx→t=A→x→tdt+Bx→tdW→t, where dW→ is the random Wiener process with the properties of the zero mean and mean square value proportional to dt  . The unknown parameters A→ and B are determined by the Fokker-Planck equation

associated with equation  (3), which in the three-dimensional version reads: equation(4) dx→t=ux→tvx→twx→tdt+2DX0002DY0002DZZ1Z2Z3dt, where Z1, Z2, Z3 are the independent random numbers normally distributed around a zero mean value and unit variance, and D1, D2 and D3 are the diffusive coefficients. Particles in a Lagrangian discrete parcels model are most of the time situated at off-grid points. The bilinear interpolation is used to interpolate the velocities in space. Processes that alter the oil’s characteristics begin immediately after an oil spill on the sea surface. Some of these processes, such as evaporation, emulsification, dissolution, photo-oxidation and biodegradation, are primarily controlled by the characteristics of the oil itself (Korotenko et al., 2001, Korotenko Venetoclax solubility dmso et al., 2004 and Korotenko et al., 2010). Different processes dominate during the time elapsing from the beginning of the spill. Evaporation is the most intense immediately after the spill, subsiding gradually over a period of 1 000 hours (Wheeler 1978). Emulsification continuously increases its effect in

the first 100 hours after the spill and then weakens in the subsequent period up to 1 000 hours (Wheeler 1978). Dissolution also takes place soon after the spill (1 hour), gradually increasing over a period of 50 hours, and weakening in the next 1 000 hours (Wheeler 1978). Photo-oxidation is activated CHIR-99021 mw shortly after the spill, and makes a contribution over an extended period of 10 000 hours but with a generally less pronounced impact than the previously mentioned factors (Wheeler 1978). Biodegradation and sinking come into play only at a later stage, 600 hours after the occurrence of the oil spill (Wheeler 1978). In addition to these processes, a very important parameter in the overall mechanism of oil pollution transport is the three-dimensional flow field with a corresponding dispersive mechanism that is continually present. In this study, the main focus is on the dominant processes that cause significant short-term changes in oil characteristics over time: spreading, evaporation, dispersion and emulsification.