John M. Lund

Control of coordinated patterns for ocean sampling

A class of underwater vehicles are modelled as Newtonian particles for navigation and control. We show a general method that controls cooperative Newtonian particles to generate patterns on closed smooth curves. These patterns are chosen for good sampling performance using mobile sensor networks. We measure the spacing between neighbouring particles by the relative curve phase along the curve. The distance between a particle and the desired curve is measured using an orbit function. The orbit value and the relative curve phase are then used as feedback to control motion of each particle. From an arbitrary initial configuration, the particles converge asymptotically to form an invariant pattern on the desired curves. We describe application of this method to control underwater gliders in a field experiment in Buzzards Bay, MA in March 2006.

CLIMODE Subsurface Mooring Report: November 2005 - November 2007

Funding was provided by the Division of Ocean Sciences of the National Science Foundation under Grant No. OCE-0424536.

At Sea Test 2 recovery cruise : Cruise 206 on board R/V Knorr April 10 - 15, 2012 Woods Hole - Woods Hole, MA

Funding was provided by the National Science Foundation contract #SA9-10 through the Consortium for Ocean Leadership

At Sea Test 2 deployment cruise : cruise 475 on board R/V Oceanus September 22 – 26, 2011 Woods Hole –Woods Hole, MA

Funding was provided by the National Science Foundation through the Consortium for Ocean Leadership

CLIVAR Mode Water Dynamics Experiment (CLIMODE), Fall 2006 R/V Oceanus Voyage 434, November 16, 2006-December 3, 2006

Abstract : CLIMODE (CLIVAR Mode Water Dynamics Experiment) is a research program designed to understand and quantify the processes responsible for the formation and dissipation of North Atlantic subtropical mode water also called Eighteen Degree Water (EDW). Among these processes, the amount of buoyancy loss at the ocean-atmosphere interface is still uncertain and needs to be accurately quantified. In November 2006, cruise 434 onboard R/V Oceanus traveled in the region of the separated Gulf Stream and its recirculation, where intense oceanic heat loss to the atmosphere in the winter is believed to trigger the formation of EDW. During this cruise, the surface mooring F that was anchored in the core of the Gulf Stream was replaced by a new one, as well as two subsurface moorings C and D located on the southeastern edge of the stream. Surface drifters, ARGO and bobbers RAFOS floats were deployed, CTD profiles and water samples were also carried out. This array of instruments will permit a characterization of EDW with high spatial and temporal resolutions and accurate in-situ measurements of air-sea fluxes in the EDW formation region. The present report documents this cruise, the methods and locations for the deployments of instruments and some evaluation of the measurements from these instruments.

CLIVAR Mode Water Dynamics Experiment (CLIMODE) Fall 2005 R/V Oceanus Voyage 419, November 9, 2005 - November 27, 2005

Abstract : CLIMODE (CLIVAR Mode Water Dynamic Experiment) is a program designed to understand and quantify the processes responsible for the formation and dissipation of North Atlantic subtropical mode water, also called Eighteen Degree Water (EDW). Among these processes, the amount of buoyancy loss at the ocean-atmosphere interface is still uncertain and needs to be accurately quantified. In November 2005, a cruise was made aboard R/V Oceanus in the region of the separated Gulf Stream, where intense oceanic heat loss to the atmosphere is believed to trigger the formation of EDW. During that cruise, one surface mooring with IMET meteorological instruments was anchored in the core of the Gulf Stream as well as two moored profilers on its southeastern edge. Surface drifters, APEX floats and bobby RAFOS floats were also deployed along with two other moorings with sound sources. CTD profiles and water samples were also carried out. This array of instruments will permit a characterization of EDW with high spatial and temporal resolutions, and accurate in-situ measurements of air-sea fluxes in the formation region. The present report documents this cruise, the instruments that were deployed and the array of measurements that was set in place.