Characterization and Evaluation of the At-Sea Performance of the Airborne Expendable Kd and Temperature Probe
Abstract
This report documents the performance of the Airborne Expendable Vertical Attenuation (Kd) and Temperature (AXKT) Probe manufactured by Sippican Incorporated during three at-sea evaluation tests. The tests include clear and overcast sky conditions with relatively calm seas for all tests. The test locations include a Norwegian fjord and nearshore and offshore sites in the Northwest Pacific Ocean. The performance of the AXKT is evaluated relative to shipboard measurements of the vertical attenuation coefficient, Kd, from 15 to 100 m. Despite several potential design weaknesses that can be corrected, the AXKT showed that it has potential to measure Kd to 200 m in waters with Kd values less than 0.06 m-1. This is a detection range of 12 (product of Kd and maximum depth of valid signal). In comparison with shipboard measurements, the AXKT: (1) exceeded the depth capabilities of shipboard measurement systems; (2) was generally within 10% of the shipboard-derived Kd when multiple probes were used, with departures of 20 to 40% for a single probe in regions of high optical or temperature variability; and (3) exhibited trends for unresolved systematic departure of Kd relative to those obtained with shipboard systems. AXKT, Shipboard measurement system.
Document Details
- Document Type
- Technical Report
- Publication Date
- Mar 21, 1994
- Accession Number
- ADA278210
Entities
People
- Alan Dean Weidemann
- Michael Wilcox
Organizations
- United States Naval Research Laboratory