Abstract:
Recent advances in processing velocity data from bottom-mounted Acoustic Doppler Current Profilers
(ADCPs) offer the capability of partitioning directional wave specctra of surface wave height in order to
separate locally generated wind waves from swell. In the study described here, we have partitioned directional
wavee spectra, derived from bottom-mounted ADCP measurements at the Martha’s Vineyard Coastal
Observatory (MVCO) south of Martha’s Vineyard, MA, into dominant swell and locally generated wind-wave
components. The partitioning was carried out following the method of Hanson and Phillips (2001) using an
exploratory approach. As part of tthis approach, we assessed the validity of the ADCP-derived wave spectra
by comparing them with one-dimensional wavee spectra derived from laser altimeter measurements. This
comparison identified a frequency range over which the ADCP-derived wave field may be suspeect. We also
carried out a series of sensitivity tests in which we evaluated how the results of wave partitioning according to
the Hanson and Phillips (2001) method is influenced by varying the parameters required to implement the
method. In this report, we describe and assess the data sources used in our study, outline the methods
employed for wave spectra partitioning and describe partitioning results.
