correct comment to show stencil behaviour
add contours on SP plot
change interpolation scheme, add wind forcing
allow for linear only interpolation, differentiation
remove superfluous plot command
take a PSD using ddzinterp to fill nans
add cases for order 1
test the interpolated PDS command
describe mathematical basis of ddzinterp
modify the plots so that spectrograms overlap
use 3 minute averages and use interpolated spectra

also use weighted PSD Pxf = Px.*f which represents the momentum of the
waves at a given frequency
only interpolate if needed
interpolate then smooth the data before taking spectra.
create DAGsfcflux.m to replace surfaceflux.m
use DAGsfcflux, use appropriate S,T for rho
use only dag files
change plotting ranges to refect new run
change # to % for matlab compatibility
scale rain to rain rate
use common plot layout