2026-07-072026-07-07http://salesiana.dossiersoluciones.com/handle/123456789/150498Advection of a passive scalar $θ$ in $d=2$ by a large-scale velocity field rapidly changing in time is considered. The Gaussian feature of the passive scalar statistics in the convective interval was discovered in \cite{95CFKLa}. Here we examine deviations from the Gaussianity: we obtain analytically the simultaneous fourth-order correlation function of $θ$. Explicit expressions for fourth-order objects, like $\langle(θ_1-θ_2)^4\rangle$ are derived.4 pages, RevTex 3.0, To appear in JETP Lett. {\bf 61}, (1995)Chaotic Dynamicstext