We survey the newly developed Hilbert spectral analysis method and its appl
ications to Stokes waves, nonlinear wave evolution processes, the spectral
form of the random wave field, and turbulence. Our emphasis is on the inade
quacy of presently available methods in nonlinear and nonstationary data an
alysis. Hilbert spectral analysis is here proposed as an alternative. This
new method provides not only a more precise definition of particular events
in time-frequency space than wavelet analysis, but also more physically me
aningful interpretations of the underlying dynamic processes.