Observations of infragravity waves at the Monterey ocean bottom broadband station (MOBB)
نویسندگان
چکیده
[1] Infragravity waves can be observed at the 1000 m deep ocean bottom broadband seismic station MOBB on stormy as well as quiet days. When compared to the energy of the short-period ocean waves recorded at the local buoys, infragravity waves in the longer than 20 s period band are found to be mainly locally generated from shorter-period waves. Two types of modulation of the infragravity signal are observed. First, the entire infragravity band signal is modulated in-phase with tides, possibly as a result of the nonlinear exchange of energy between the short-period waves and tidal currents. Second, a longer-period modulation of the infragravity signal is observed and is best correlated with the energy of the 14 s period ocean waves. This correlation indicates that the mechanism of generation of double frequency microseisms and infragravity waves are likely strongly related. Previously recorded data during the Oregon ULF/VLF experiment at 600 m water depth also indicate that infragravity waves are primarily locally generated.
منابع مشابه
The Monterey Bay broadband ocean bottom seismic observatory
We report on the installation of a long-term buried ocean-floor broadband seismic station (MOBB) in Monterey Bay, California (U.S.A.), 40 km off-shore, at a water depth of 1000 m. The station was installed in April 2002 using a ship and ROV, in a collaborative effort between the Monterey Bay Aquarium Research Institute (MBARI) and the Berkeley Seismological Laboratory (BSL). The station is loca...
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