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[This space left intentionally blank]. Is a sum of random waves a good model of the internal wave field?. or, an informal look at non-stationarity. Murray Levine. where. independent random variables. u. time. u-spectrum. frequency. Interesting information
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Is a sum of random waves a good model of the internal wave field? or, an informal look at non-stationarity Murray Levine where independent random variables
u time
u-spectrum frequency
Interesting information in the modulations?
u-spectrum frequency
Random phase u time
u time
High frequency Band u-spectrum time
Random phase u time
High frequency Band u-spectrum time
So, look for the modulation of spectral bands… Are the modulations consistent with the random wave model? Use data from the Ocean Storms experiment Moored Observations NE Pacific Ocean 47deg 25’N, 139 deg 18’W 1987-88
10 month time series Ocean Storms 194 m u-spectrum -2 Frequency, cph 0.1 1
0.1 cph 0.5 cph 1.2 cph Spectrum as function of t, S(t) Ocean Storms 194 m u-spectrum 300 0 time, days
0.1 cph 0.5 cph 1.2 cph Spectrum of S(t) Ocean Storms 194 m 1/(300 days) 1/(10 days) frequency
0.1 cph 0.5 cph Ocean Storms 2000 m Spectrum as function of t, S(t) u-spectrum 300 0 time, days
0.1 cph 0.5 cph Spectrum of S(t) Ocean Storms 2000 m u-spectrum frequency 1/(300 days) 1/(10 days)
0.1 cph 0.5 cph 1.2 cph Spectrum as function of t, S(t) Random Model u-spectrum 300 0 time, days
0.1 cph 0.5 cph 1.2 cph Spectrum of S(t) Random Model 1/(300 days) 1/(10 days) frequency
u-spectrum frequency
Another Random phase u time
So, is the internal wave field look like this random phase model? Ie is each freq band treated this way Or is there information in the modulations, ie the non-stationary part To investigate this idea a bit further use data from Ocean Storms experiment Open NE pacific, 1987-88, 47deg 25’N 139 deg 18’W So, Look at time varying spectra and see if random phase works. Ie, similar question: can we generate a realisitic iw field by random phase? Or stated another way: is there information about the wave field in these modulations Break up the spectrum into bins