We introduce a time-dependent Eulerian-Lagrangian length-scale and an inverse locality hypothesis which explain scalings of second order one-particle Lagrangian structure functions observed in Kinematic Simulations (KS) of homogeneous isotropic turbulence. Our KS results are consistent with the physical picture that particle trajectories are more/less autocorrelated if they are smoother/rougher as a result of encountering less/more straining stagnation points, thus leading to enhanced/reduced turbulent diffusion.
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