Inert tracers in 2d turbulence Garrett, C. (1983). Dynamics of Atmospheres and Oceans, 7, 265-277
		Consider an initially very small patch of tracer. 3 regimes:    L<LS,     spreads diffusively, k=ks    LS<L<LL,   filamented    LL<L,     spreads diffusively, k=kl        Lengthscales:            LS=Ö(ks/g)            LL= Ö(kl/g)