  Recent work on Lagrangian descriptors has shown that Lyapunov Exponents can
be applied to observed or simulated data to characterize the horizontal
stirring and transport properties of the oceanic flow. However, a more detailed
analysis of regional dependence and seasonal variability was still lacking. In
this paper, we analyze the near-surface velocity field obtained from the Ocean
general circulation model For the Earth Simulator (OFES) using Finite-Size
Lyapunov Exponents (FSLE). We have characterized regional and seasonal
variability. Our results show that horizontal stirring, as measured by FSLEs,
is seasonally-varying, with maximum values in Summer time. FSLEs also strongly
vary depending on the region: we have first characterized the stirring
properties of Northern and Southern Hemispheres, then the main oceanic basins
and currents. We have finally studied the relation between averages of FSLE and
some Eulerian descriptors such as Eddy Kinetic Energy (EKE) and vorticity (w)
over the different regions.
