ACM3 (Deep Basin Southwestern Boundary - US component)

This component of the Deep Basin experiment produced 17 current meter records from 6 moorings. From here you can

If you download any of the records you should read the note on file format.

mooringinstr depthinstr typedatesmetadatadownload
DB1 (WHOI 906) 509 meters VACM 05 Jan 91 - 01 Aug 92 view metadata download record
DB1 (WHOI 906) 908 meters VACM 05 Jan 91 - 03 Dec 92 view metadata download record
DB1 (WHOI 906) 2609 meters VACM 05 Jan 91 - 03 Dec 92 view metadata download record
DB1 (WHOI 906) 3532 meters VACM 05 Jan 91 - 03 Dec 92 view metadata download record
DB2 (WHOI 907) 496 meters VACM 06 Jan 91 - 27 Oct 92 view metadata download record
DB2 (WHOI 907) 895 meters VACM 06 Jan 91 - 13 Apr 91 view metadata download record
DB2 (WHOI 907) 2595 meters VACM 06 Jan 91 - 03 Dec 92 view metadata download record
DB2 (WHOI 907) 2995 meters VACM 06 Jan 91 - 03 Dec 92 view metadata download record
DB2 (WHOI 907) 3850 meters VACM 06 Jan 91 - 03 Dec 92 view metadata download record
DB3 (WHOI 908) 2592 meters VACM 07 Jan 91 - 04 Dec 92 view metadata download record
DB3 (WHOI 908) 3918 meters VACM 07 Jan 91 - 04 Dec 92 view metadata download record
DB4 (WHOI 909) 514 meters VACM 08 Jan 91 - 04 Dec 92 view metadata download record
DB4 (WHOI 909) 914 meters VACM 08 Jan 91 - 04 Dec 92 view metadata download record
DB4 (WHOI 909) 2614 meters VACM 08 Jan 91 - 04 Dec 92 view metadata download record
DB4 (WHOI 909) 3714 meters VACM 08 Jan 91 - 04 Dec 92 view metadata download record
DB5 (WHOI 910) 2597 meters VACM 09 Jan 91 - 19 Feb 93 view metadata download record
DB6 (WHOI 912) 2587 meters VACM 12 Jan 91 - 07 Dec 92 view metadata download record

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Brief description of ACM3

The Deep Basin Experiment took place in and around the Brazil Basin, a region west of the Mid-Atlantic Ridge stretching from the Ceara Rise near the equator in the north, to the Santos Plateau - Rio Grande Rise system near 30 deg S. A principal objective was to understand the mean circulation below the thermocline; the Brazil Basin was selected because it is a region of expected low eddy KE, a useful attribute in a program aimed at the mean flow.

Five current meter arrays were deployed at passages that connect the Brazil Basin to neighboring regions. Each array was in the water for approximately two years. We are concerned here with a line of 13 moorings that was installed jointly by IFM-Kiel and the Woods Hole Oceanographic Institute, along the southwestern boundary of the basin. Six of the moorings were deployed by WHOI and have been assigned the WOCE designation ACM3. The remaining 7 moorings (one of which was not recovered) were deployed by IFM-Kiel and comprise ACM12. All of the moorings were installed during January 1991; 5 of the ACM3 moorings were recovered during December 1992, and one during October 1993.

The joint array extended in a line running from the edge of the continental shelf, southeastward across the Santos Plateau and the Vema Channel, to the Rio Grande Rise (see map). The goal was to measure inflow and outflow along the southern boundary of the Brazil Basin. For a detailed description of the purpose and rationale of this segment of the experiment, as well as data plots and statistics, see the joint technical report WHOI-94-07, IFM-Kiel 243. In addition, there is a relevant note in WOCE Newsletter #17, dated November 1994. See also

Zenk, W., K.G. Speer and N.G. Hogg (1993): Bathymetry at the Vema Sill. Deep-Sea Res. I, 40(9), 1925-1933.

Zenk, W. and N.G. Hogg (1996): Warming trend in Antarcic Bottom Water flowing into the Brazil Basin. Deep-Sea Res. I, 43(9), 1461-1473.

Hogg, N.G., W.B. Owens, G. Siedler and W. Zenk (1996): Circulation in the deep Brazil Basin. In The South Atlantic (ed. G. Wefer, et al). Berlin: Springer. 644pp, pp249-260.

Boebel, O., C. Schmid and W. Zenk (1997): Flow and recirculation of Antarctic Intermediate Water across the Rio Grande Rise. J. Geophys. Res., 102(C9), 967-986.

Hogg, N.G. and W. Zenk (1997): Long-period changes in the bottom water flowing through Vema Channel. J. Geophys. Res., 102(C7), 15639-15646.

Mueller, T.J., Y. Ikeda, N. Zangenberg and L.V.Nonato (1997): Direct measurements of western boundary currents off Brazil between 20S and 28S, J. Geophys. Res., 103(C3), 5429-5437.

Hogg, N.G. and W.B. Owens (1999): Direct measurements of the deep circulation within the Brazil Basin. Deep-Sea Res. II, 46(1/2), 335-353.

Hogg, N.G., G. Siedler and W. Zenk (1999): Circulation and variability at the southern boundary of the Brazil Basin, J. Phys. Oceanogr., 29(2), 145-157.

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Format of the current records

These files have been compressed with the ZIP compression utility. After downloading them, you will need to expand them. On a PC that is running Microsoft Windows, WinZip or Pkunzip will do the job. Under Linux, gunzip will expand these files. Other utilities are available for the UNIX and Macintosh environments (for example, unzip and/or gunzip are present on most UNIX systems). After expansion, you will have binary files in the netCDF format.

netCDF is a self-documenting format that can be accessed by a variety of software tools. We have included here a Matlab script that can be used to read netCDF current records in an environment that contains the Matlab/netCDF interface created by CSIRO. You can Click here to learn more about netCDF.

We are aware that users who are unfamiliar with netCDF or who lack software to deal with it, may find the netCDF format more a deterrent than an aid to effective use of the data. We have included in this CDROM set a second disk that is identical to this one, except that the current meter records have OSU's "Stranger" format. The Stranger format, like netCDF, is self-documenting but utilizes the ASCII code. It is easily readable by both humans and computers; you may find it preferable to netCDF.

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