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5-minute Mean Currents over Sand City ADCP for last 2 Days
Vertical profiles of currents from 12m depth to surface are made with this acoustic doppler current profiler mounted on the 1m high instrument frame. Current vectors (cross-shore and along-shore components) are measured every 0.5m up to the surface. A two day timeseries of the most recent current components is shown in the color contour plots below. These data have been averaged to 5 minute intervals to remove variations caused by waves. The blue to red color scale corresponds to a -0.2 to +0.2 m/s magnitude (Note that this is double the range of the MISO ADCP 5-minute mean plot). If the currents are moving uniformly through the water column, these timeseries appear as vertical stripes, whereas current gradients, or vertical shear, have color changes in the vertical. The upper 1 to 2 bins of data from the instrument is contaminated by an acoustic reflection from the water surface. The sinusoidal shape results from tidal water depth variations. The time axis is yeardays, where yearday 1.000 is the start of 1 January.
Please note, all times displayed here are Universal Time (UT), and plots are updated hourly.
5 Min. Mean ADCP Cross Shore Velocity |
5 Min. Mean ADCP Along Shore Velocity |
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 Currents over Sand City ADCP for most recently available 2 minutes
The current data below was also collected by the same acoustic doppler current profiler noted above. This 2 minute timeseries shows currents at the original 1 sample per second data rate, representing wave velocities. Here the velocity range has been expanded so that the blue to red color scale corresponds to a -0.5 to +0.5 m/s magnitude.
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 Frequency-Directional Spectrum, Sand City
The spectrum shown below was calculated using the Maximum Entropy Method with sixty minutes of P,U, and V data. It has a frequency resolution of 0.005Hz, directional resolution of 1 degree, and approximately 35 degrees of freedom.
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 Pressure over Sand City ADCP for last 4 days
The acoustic doppler current profiler records pressure in decibars, one sample every 30 seconds. This timeseries shows 5-minute meaned pressure values recorded over the most recent 4 days.
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