| Relative dispersion has been examined previously with data from the
atmosphere, ocean and turbulence simulations. The focus of such
studies is generally on the dispersion, the second order moment of
pair separations, or on related measures like the Finite Scale
Lyapunov Exponent (FSLE). Relatively little attention has been paid to
the probability density functions (PDFs) of the displacements, from
which the moments derive. Here we examine PDFs from three sources: 1)
synthetic particles in numerical simulations of 2-D turbulence, 2)
balloons in the stratosphere and 3) surface drifters in the ocean. We
also compare how the evolving PDFs compare to analytical
predictions. The results inform us about the kinetic energy spectra in
the respective systems. The sub-deformation scales in the atmosphere
and ocean are of particular interest. |