1 the canyon axis. All of these measurements are about 5 meters off the 



2 bottom. What I'm showing is the energy distribution as a function of 



3 frequency. 



4 So, energy here and frequency here, periods from 2 hours to about 



5 500 hours. I want to make two major points. First, and we're showing 



6 both the alongshelf, on the shelf, and slope. We're looking at the 



7 alongshelf component of flow, and in the canyon we're looking at the up 



8 canyon component of flow in the solid line. 



9 I'll only talk about the solid line. On the shelf we see a large 



10 amount of energy at lower frequencies, periods of a few days or longer, 



11 which are forced by the winds, both on the shelf and on the slope. 



12 That energy is completely absent within the canyon, so we see ^ery 



13 little influence of wind-driven motions or low-frequency variability 



14 within the canyons. 



15 At all stations we see a major peak in the semidiurnal tide, this 



16 major peak mark in red, but in the canyon, we see a major increase in 



17 the high frequency motions in the 2 to 10 hour period from the deep 



18 stations to the shallower stations. 



19 We'll see in some of the current-meter records that the high 



20 frequency motions are very energetic in the canyons, they increase from 



21 shallow to deep, and those are virtually absent on the adjacent shelf. 



22 The overall point that I want to make from this slide is that the 



23 general statistics, and the currents and the frequencies at which they 



24 fluctuate, are very different from the shelf, the slope, and within the 



25 canyon, and they change drastically within the canyon. 



26 If we sort of think of the fluctuations in these five frequency 



27 bands, high-frequency flows with periods between 2 and 10 hours, the 



28 semidiurnal tides, the inertial flows, the diurnal, and low frequencies. 



29 In this region of the continental shelf, fluctuations, if you want 



30 to understand the circulation in this area, fluctuations at all these 



31 frequencies are important. It's one of the few areas on the shelf in 



32 which that's the case. 



33 Just look at the upper panel here. This is a station at LCB, near 



34 the canyon head and 300 meters. This shows the orientation of the 



23 



