Abstract
The Gulf of Mexico circulation is modulated by a mesoscale current, the
Loop Current (LC), and large anticyclonic eddies that detach from it.
The LC dynamics are recurrent, and its evolution is in and from a few
preferential states. This observation points to the existence of a
low-dimensional dynamical attractor. Building upon advancements in
dynamical system theory, this work characterizes the average and
instantaneous dimensions of such an attractor. The instantaneous
dimension and its evolution in time are compared among an
altimeter-based dataset, an ocean reanalysis and an operational
hindcast. The LC complexity, measured by its dimension, differs among
them, especially when the dimension is high. During shedding events, on
the other hand, differences between datasets emerge in the second
principal component. The information provided by this analysis is
relevant to operational ocean forecasts and points to where improvement
should occur.