Identification

Title

Polaris: a GPS-navigated ocean acoustic current profiler

Abstract

Results from an initial feasibility study to test whether Global Positioning System (GPS) navigation can be combined with more traditional acoustic methods to measure ocean current profiles are presented. A typical acoustic current profiler such as PEGASUS measures currents by ranging on two acoustic sources (one-way beacons or two-way transponders) as it falls or rises through the water column. These sources must be previously deployed on the bottom, and their positions accurately determined via the attending research vessel. As discussed below, this procedure introduces a number of complications. In particular, any unresolved errors in the source deployment will remain as systematic errors in the resulting velocity data. The method described here replaces the bottom-mounted sources with hydrophones drifting near the ocean surface. The positions of these hydrophones are computed every few seconds using GPS. This feasibility test shows that a combined GPS-acoustic system can approach accuracy levels found in the standard method. Furthermore, systematic errors can be significantly reduced. Random errors are estimated to be approximately ±1–2 cm s⁻¹ dependent on station geometry.

Resource type

document

Resource locator

Unique resource identifier

code

https://n2t.org/ark:/85065/d7p270q3

codeSpace

Dataset language

eng

Spatial reference system

code identifying the spatial reference system

Classification of spatial data and services

Topic category

geoscientificInformation

Keywords

Keyword set

keyword value

Text

originating controlled vocabulary

title

Resource Type

reference date

date type

publication

effective date

2016-01-01T00:00:00Z

Geographic location

West bounding longitude

East bounding longitude

North bounding latitude

South bounding latitude

Temporal reference

Temporal extent

Begin position

End position

Dataset reference date

date type

publication

effective date

1995-06-01T00:00:00Z

Frequency of update

Quality and validity

Lineage

Conformity

Data format

name of format

version of format

Constraints related to access and use

Constraint set

Use constraints

Copyright 1995 American Meteorological Society (AMS). Permission to use figures, tables, and brief excerpts from this work in scientific and educational works is hereby granted provided that the source is acknowledged. Any use of material in this work that is determined to be "fair use" under Section 107 or that satisfies the conditions specified in Section 108 of the U.S. Copyright Law (17 USC, as revised by P.L. 94-553) does not require the Society's permission. Republication, systematic reproduction, posting in electronic form on servers, or other uses of this material, except as exempted by the above statements, requires written permission or license from the AMS. Additional details are provided in the AMS Copyright Policies, available from the AMS at 617-227-2425 or amspubs@ametsoc.org. Permission to place a copy of this work on this server has been provided by the AMS. The AMS does not guarantee that the copy provided here is an accurate copy of the published work.

Limitations on public access

None

Responsible organisations

Responsible party

contact position

OpenSky Support

organisation name

UCAR/NCAR - Library

full postal address

PO Box 3000

Boulder

80307-3000

email address

opensky@ucar.edu

web address

http://opensky.ucar.edu/

name: homepage

responsible party role

pointOfContact

Metadata on metadata

Metadata point of contact