Dataset: adcp
Deployment: OC336

Acoustic Doppler Current Profiler Data

ADCP data from the U.S. GLOBEC Georges Bank Program are available from a web site maintained by Dr. Charles Flagg presently located at SUNY Stony Brook. ADCP data from moorings at the Northeast Peak and Southern Flank are available separately.

Data are retrieved by cruise directly from the database via user supplied selection criteria. The data are returned in either .mat file or plain ASCII files. Output includes yearday, lon, lat, depth(m), u(m/s), v(m/s), backscatter intensity, estimated zooplankton biomass, water temp, and water depth.

The web-page contains the results of the shipboard ADCP data collection effort for GLOBEC's Georges Bank Project. The ADCP data has been acquired onboard the RV Endeavor, the RV Oceanus, the Edwin Link, and the Albatross IV for each GLOBEC cruise. At the end of each cruise the pingdata files are sent to us for processing. The vast majority of the data has been collected using 150 kHz narrow-band ADCPs although there have been a number of cruises on the RV Albatross which is equipped with a broad-band unit. Recently, we have completed the modification and development of the routines required to deal with the broad-band data and those cruises are now being gradually included in the ADCP archive.

The ADCP data are processed using the CODAS3 shipboard ADCP processing programs developed by the University of Hawaii with additional capabilities developed at Brookhaven. As the data from each cruise is processed, it is made accessible through this web page which allows for the downloading of user specified portions from each cruise in either flat-ASCII or mat file formats. Cruise plots are available for viewing which show the spatial extent of the data coverage for each cruise. The broadscale cruises typically provide the widest coverage although some of the process cruises have excellent coverage in limited areas.

The assistance of Bill Fanning, Jim Akens, Laura Goepfert, Melissa Lamont, and Jim Manning in overseeing the shipboard collection and forwarding of the ADCP data to BNL is gratefully acknowledged.

As part of the analysis of the ADCP data set, we have embarked upon a hindcast modelling effort based upon the work of the Dartmouth/UNC/WHOI/NMFS/BIO/BNL realtime modelling program. The goal is to provide realistic spatial and temporal interpolations of the ADCP currents over the Bank for as many cruises as possible in order to study the large-scale mean and seasonal flow patterns. The hindcast process uses a fully non-linear forward model and a variety of linearized inverse models in an iterative procedure to capture as much of the observed variability in the ADCP data as possible. The resulting model fields then provide a reasonable spatial and temporal prediction of the currents and property distributions over the Bank during the cruise period. Results from the hindcast modelling are also being made accessible through this web site as they become available. The basic results of the model come in the form of hourly barotropic currents and sea-level and complete 3-D results for the model domain at six-hourl y intervals. The current version of the hindcast model uses the Bank150 grid, a map of which can be viewed by clicking here. The invaluable assistance of Chris Naimie, Jim Manning and Brian Blanton in setting this program up is much appreciated.

* PLEASE NOTE: A minor calibration error was detected and corrected. All of the necessary corrections were performed between 7/28/00 to 10/3/00.

* Due to an erroneous dip switch toggle on the Endeavor ADCP (discovered by Jules Hummond and Daryl Symonds), the 1999 Endeavor ADCP data contained errors. The errant profiles (approx 2%) were removed and affected datasets completely reprocesses on 3/12/01.

Questions regarding these data should be directed to:

Dr.  Charles Flagg 
Marine Science Research Center 
Stony Brook University 
Stony Brook, NY 11794-5000 
PHONE:(631) 632-3184 
FAX:  (631) 632-8820 
EMAIL:cflagg@ms.cc.sunysb.edu

or

Maureen Dunn 
maudunn@notes.cc.sunysb.edu  
Marine Science Research Center 
Stony Brook University, NY 11794-5000

Last update:  December 12, 2006