The ADCP data can be obtained from the Shipboard ADCP Center (SAC) at the University of Hawaii at the URL http://ilikai.soest.hawaii.edu/sadcp/ or via anonymous FTP (kapau.soest.hawaii.edu).
CODAS (Common Oceanographic Data Analysis System ) source code, libraries, executables, documentation and demo, archived as codas3.exe (PC version) and codas3.tar.Z (Sun4 version), are ... available via anonymous FTP (noio.soest.hawaii.edu) in subdirectory pub/codas3.
TOGA COARE was a multidisciplinary, international research effort that investigated the scientific phenomena associated with the interaction between the atmosphere and the ocean in the warm pool region of the western Pacific. The field experiment phase of the program took place from 1 November 1992 through 28 February 1993 and involved the deployment of oceanographic ships and buoys, several ship and land- based Doppler radars, multiple low and high-level aircraft equipped with Doppler radar and other airborne sensors, as well as a variety of surface based instruments for in situ observations.
SHIPBOARD ADCP CENTER (SAC) AT THE UNIVERSITY OF HAWAII
The NODC established the SAC at the TOGA Sea Level Center at the University of Hawaii for the acquisition, review, documentation, archival, and distribution of shipboard ADCP datasets. These high-density datasets, which have been passed through quality control, calibration, and navigation stages, are placed in the so-called "CODAS" format. The datasets are then reviewed, reduced to a standard subset, documented, and backed up. Datasets are periodically passed on to NODC headquarters, which acts as the final repository.
ADCP DATA COLLECTION METHODOLOGY
The hull-mounted ADCP estimates horizontal and vertical velocity as a function of depth by using the Doppler effect to measure the radial relative velocity between the instrument and scatterers in the ocean. Three acoustic beams in different directions are the minimal requirement for measuring the three velocity components. A fourth beam adds redundancy and an error estimate. The ADCP transmits a ping from each transducer element roughly once per second. The echo arrives back at the instrument over an extended period, with echoes from shallow depths arriving sooner than ones from greater ranges. Profiles are produced by range-gating the echo signal, which means the echo is broken into successive segments called depth bins. These correspond to successively deeper depth ranges. The operator configures the length of each depth bin and transmit pulse, which determines the degree of averaging in the vertical, depending on whether one is more interested in vertical resolution or profile penetration. The noisy velocity estimates from each ping are vector-averaged into 1- to 10-minute ensembles. The relative velocities are rotated from the transducer's reference to the earth's reference frame using the ship's gyrocompass. Finally, relative velocities and various ancillary parameters are stored on the ship using a data acquisition system (DAS). The DAS optionally records navigation information, such as provided by the GPS. Specifics of the instrument capabilities and configuration options are well documented (RDI, 1989).
Two types of shipboard ADCP data are available:
- Densely-sampled sets (10 MB per cruise-month) as CODAS binary block files of the currents, and ancillary data at the interval with which the data were recorded and processed.
- ASCII standard subsets of the currents, ship's speed, and transducer temperatures at hourly and 10-m depth intervals.
For each cruise, a metadata file is prepared summarizing specifics about the instrumentation, cruise activities, data processing, and calibration.
The standard ASCII subset and metadata files are maintained on-line in an anonymous FTP area and are available free of charge. Data types, metadata files, inventories, and cruise tracks can also be obtained via conventional storage media (diskettes or DAT, eXabyte, or magnetic tapes) for a fee. The densely-sampled dataset can be made available on anonymous FTP on a case-by-case basis. In general, NODC products and services are provided on a cost recovery basis. However, researchers who submit data to NODC are eligible to receive NODC data on exchange. For charges, consult the UHI/SAC URL (http://ilikai.soest.hawaii.edu/sadcp/obtain.html) or contact Patrick Caldwell (firstname.lastname@example.org).
caldwell at hawaii.edu, patrick.caldwell at noaa.gov
Liaison for Hawaii and US-Flag Islands in the Pacific
Department of Oceanography
School of Ocean and Earth Science and Technology
University of Hawaii at Manoa
1000 Pope Road, MSB 316
First Institute of Oceanography, SOA
13 Hongdao Road
Province or State:
Postal Code: 266003
Delcroix, T., G. Eldin, C. Henin, F. Gallois, J. Grelet, M. Inall, S. Keene, M.J. Langlade, C. Mekes, F. Masia, K. Richards, 1993: Campagne COARE-POI a bord du N.O. Le Noroit 1er decembre 1992 - 2 mars 1993. Rapports de Missions, Sciences de la Mer, Oceanographie Physique, No. 10, ORSTOM, Centre de Noumea, 338 pp.
Firing, E., 1992: Notes from Acoustic Doppler Current Profiler Workshop at the National Oceanographic Data Center, May 14-15, 1992. "unpublished manuscript." (Copies available from P. Caldwell).
Pu, S., S. Jian, E. Zou, J. Zhan, K. Yeng, F. Yu and G. Zhang, 1993: The TOGA-COARE Cruise of R/V Xiang Yang Hong #5, State Oceanic Administration, China Ocean Press, 574 pp.
RD Instruments, 1989: Acoustic Doppler Current Profilers, Principles of Operation: A Practical Primer. RD Instruments, 9855 Businesspark Av., San Diego, CA 92131.
TOGA COARE International Project Office (TCIPO), 1992: TOGA COARE Operations Plan, Working Version September 1992. University Corporation for Atmospheric Research, Boulder, CO 80307, 138 pp.
TOGA COARE International Project Office (TCIPO), 1993: TOGA COARE Intensive Observing Period Operations Summary. University Corporation for Atmospheric Research, Boulder, CO 80307, 505 pp.
TOGA COARE International Project Office (TCIPO), 1994: Summary Report of the TOGA COARE International Data Workshop, Toulouse, France, 2 - 11 August 1994, University Corporation for Atmospheric Research, Boulder, CO 80307, 170 pp.
Webster, P.J., and R. Lukas, 1992: TOGA COARE: The Coupled Ocean- Atmosphere Response Experiment. Bull. Am. Meteorol. Soc. 73, 1377-1416.
World Climate Research Programme (WCRP), 1985: Scientific Plan for the TOGA Coupled Ocean-Atmosphere Response Experiment. WCRP Publications Series, No. 3 Addendum, World Meteorological Organization, Geneva, 96 pp.