1 of 27 Ellesmere Island coast in Kennedy Channel, Aug.-12, 2009
Jan 01, 2016
Magnetic Compass unusuable:
Kennedy Channel ~2800 nTFram Strait ~ 5800 nT
magnetic field strength
Velocity:Long-Range
Sonars• Sonars send and receives acoustic waves• Measured Doppler shift proportional to
velocity• 75 kHz transducers
Rigid Backbone allowed toPitch and Roll, but NOTChange Heading
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High-resolution Power-spectra of Depth-averaged Flow at KS10
All frequencies
Diurnal band
Semi-diurnal band
Mean Along-Channel Velocity(cm/s)
Along-Channel Freshwater Flux(mSv per km per meter rel. to 34.8)
Along-Channel velocity fluctuations(cm/s)
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2004/05
2003/04
2005/06
Three-year along-channel currents from ADCP mooring (KS02)D
epth
(m)
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Spectral DensityVolume Flux
Spectral DensityAlong-Channel Sealevel Difference
Cumulative Varianceby frequency
Cumulative Varianceby time scale (1/frequency)
Chosen Cut-Off
Selection of Time Scale:
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Good Filter:
Bad Filter:
Filter Design
Lanczos Raised Cosine
Running Average
Cut-Off: ~20 Days
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Residual root mean square:0.19 Sv
Correlation: r2=0.71Regression: a= -0.84 SvRegression b=8.54 Sv/m