Abstract:
We present velocity observations from a shipboard acoustic Doppler current profiler (ADCP) on
R/V Wecoma during cruise W0105c (23 May to 13 June 2001). The cruise was a component
(Survey I) of the Coastal Ocean Advances in Shelf Transport (COAST) experiment. The ADCP
was an RD Instruments hull-mounted 153.6-kHz narrowband unit. Data were collected nearly
continuously using an ensemble averaging interval of 2.5 min and a vertical bin length of 8 m.
This implies an inherent short-term random uncertainty of 2 cm/s for each data point; this uncertainty
is reduced with additional space or time averaging. To reference the velocities to earth coordinates,
we used GPS navigation in combination with the ship’s gyrocompass and a GPS attitude
system. Our processing methods are generally standard ones, primarily making using of
the CODAS software package as described at http://ilikai.soest.hawaii.edu/sadcp. Overall ADCP
data quality for the cruise was excellent. To produce the vector maps here, we applied 5 km
spatial averaging. For the sections, we contoured using a two-pass Barnes method with horizontal
(vertical) smoothing of 5 km (24 m) and 2.5 km (12 m) for the first and second passes. An
online version of this report is available at http://damp.coas.oregonstate.edu/coast/adcp. In addition,
the complete data set and all processing details are available from the NODC Joint
Archive for Shipboard ADCP: http://ilikai.soest.hawaii.edu/sadcp. A cruise narrative is included
in the companion Seasoar data report (COAS Data Report 191, Ref. 2003-1) available at
http://damp.coas.oregonstate.edu/coast/seasoar. This work was funded by National Science
Foundation grant OCE-9907854.
