James R. Valdes

A Neutrally Buoyant, Upper Ocean Sediment Trap

Abstract The authors have designed and deployed a neutrally buoyant sediment trap (NBST) intended for use in the upper ocean. The aim was to minimize hydrodynamic flow interference by making a sediment trap that drifted freely with the ambient current. The principal design problem was to make the NBST descend to and stay near a prescribed depth. For a variety of reasons, the most success has been with NBSTs that were autoballasted by means of a microprocessor-controlled volume changer. Autoballasting NBSTs has demonstrated an ability to hold a prescribed depth to within 10 m. There have been two successful, concurrent deployments of NBSTs and conventional surface-tethered sediment traps (STSTs) at the Bermuda Atlantic Times Series site. During both periods the observed flow past the STSTs was low, about 0.05 m s−1, so that hydrodynamic effects on the STSTs would have been minimized. Comparisons of the trap results (described in a companion paper by Buesseler et al.) indicate that the total mass of collect...

SOFAR float Mediterranean outflow experiment data from the first year, 1984-1985

Funding was provided by the National Science Foundation under grant Nos. OCE 82-14066 and OCE 86-00055.

An FSK telemetry module for vector measuring current meters

Funding was provided by the Office of Naval Research under contract Number N00014-84-C-0134, NR 083-400.

Gulf Stream recirculation experiment - Part II

Funding was provided by the national Science Foundation under Grant Numbers OCE 81-09145 and OCE 81-17467

Eddy Seeding in the Labrador Sea: A Submerged Autonomous Launch Platform Application

AbstractTwo submerged autonomous launch platforms (SALPs) were deployed at 500-m depth on a deep-water mooring in the northeastern Labrador Sea from 2007 to 2009 to automatically release profiling floats into passing warm-core anticyclonic Irminger Rings (IRs). The objective was to investigate the rings’ vertical structure and evolution as they drifted from their formation site near the western coast of Greenland to the area of deep convection in the south-central part of the basin. Mechanically and electronically, the SALP worked well: 10 out of 11 floats were successfully released from the mooring over 2 years. However, getting floats trapped in eddy cores using a preprogrammed release algorithm based on temperature and pressure (a proxy for current speed) measured by the SALPs met with limited success mainly because 1) the floats settled at a park pressure that was initially too deep, below the volume of water trapped in the eddy core; 2) the eddies translated past the mooring much more quickly than an...

SOFAR float Mediterranean outflow experiment data from the second year, 1985-86

Funding was provided by the National Science Foundation under grant Numbers OCE 82-14066 and OCE 86-00055.