Ocean Physics MSc thesis at the University of Victoria, under the supervision of Dr. Jody Klymak, characterising the internal wave field at Barkley Canyon.
These go directly into the thesis replacing the 2013 plots at the appropriate Results sections, and inter-annual seasonality (or lack thereof) will be discussed as they appear.
A summary of any notable variability (see below) will likely be in the Discussion / Conclusions.
In most cases, there is little inter-annual variability; mean currents, spectra, frequency depth dependence, and individual frequency band seasonality are mostly similar during each analysis year.
However, sub-diurnal inter-annual seasonality is variably intermittent at Slope (but not at Axis). What is forcing the sub-diurnal band?
Near-inertial inter-annual seasonality is also variably intermittent at Slope, with only some events showing up at Axis. As expected if forcing is mostly due to sporadic regional weather events, still investigating!
Long-term evidence is difficult to find.
Drakopoulos and Marsden (1993) noted an increase in baroclinic internal tide energy on the VICS from the beginning of June that died off by September, due to expected seasonal changes in stratification.
Cummins et al. (2000) suggest that diurnal currents over the VICS is seasonally responsive to the large-scale spring shift from downwelling to upwelling mean currents, and fairly regular inter-annually (1979-82, 1984, 1996-2000).
Xu and Noble (2009) found that K1 currents around Monterey Canyon peaked in April-June and October-December, relative to the annual cycle of largest spring/neap tide amplitudes. M2 currents were a complex mix of barotropic and baroclinic forcing, and so are somewhat more consistent throughout the year. Both showed inter-annual consistency.
Examples:
Velocities (40h low-pass - Slope):
Power spectra (Rotary - Axis, will be side by side with PSD):
A summary of any notable variability (see below) will likely be in the Discussion / Conclusions.
Near-inertial inter-annual seasonality is also variably intermittent at Slope, with only some events showing up at Axis. As expected if forcing is mostly due to sporadic regional weather events, still investigating!
Xu and Noble (2009) found that K1 currents around Monterey Canyon peaked in April-June and October-December, relative to the annual cycle of largest spring/neap tide amplitudes. M2 currents were a complex mix of barotropic and baroclinic forcing, and so are somewhat more consistent throughout the year. Both showed inter-annual consistency.
Examples:
Velocities (40h low-pass - Slope):
Power spectra (Rotary - Axis, will be side by side with PSD):
Depth-frequency spectra (PSD - Axis):
Depth-band spectra (PSD - Sub-diurnal - Slope):
Depth-band spectra (Rotary - Near-inertial - Slope):