Trying Okubo Weiss parameter estimation. Doesn't seem very useful in identifying the ring aroudn the eddy.
Alternative continuity eqn budget. Doesn't work too well yet.
Playing aroudn with continuity diagnostics. One version with hsitory files looks good. Notes taken in roms.tex
added code for plotting of alongshore jet
added vorticity export to shelf code
added some eddy vorticity calculation - this is incomplete