ANFOG: Australian National Facility for Ocean Gliders Basics of an Ocean Glider Related to ARGO floats but with wings Powered by batteries (C or D cells) Buoyancy engine pumping oil or water into and out of a bladder changes density of vehicle which causes glider to sink or float Wings provide forward momentum motion through the water is a saw tooth pattern Control via a rudder or movement of battery pack fore to aft and side to
side Ocean Gliders Description Operation depth ratings 200, 1000, 5000 m Designed for launch, monitor, recover or
launch, forget, recover missions Mission duration 15 days 6 months Speed < 1 kn - typically 0.2-0.5 knts Weight 50-75 kgs in air Monitored and programmed at surface from control stations located on your desktop. R/T communications at surface via
radio link, Iridium, cell, Argos Easily deployed and recovered from small boats or docks by 1 or 2 persons Operations in all weather Typical Glider saw tooth motion Glider Manufacturers 3 groups in US building vehicles
Webb Research Slocum Glider, Thermal Glider UofW/APL Seaglider Scripps Institute - Spray Glider (now Bluefin) Slocum Electric Glider Manufactured by Webb Research, USA
Slocum Gliders Webb Research Seaglider UofW / APL Spray Glider Bluefin Scripps Spray Glider - Scripps
Development Timeline 1989 The Slocum Mission appears in Oceanography 1990 Office of Naval Technology (ONT) awards Webb Research Corporation contract for development of Slocum prototype
1991 Tests of Slocum prototype and thermal engine in Wakulla Springs FL and Lake Seneca NY 1992 First deployment of the ALBAC glider, a shuttle type glider developed at the University of Tokyo in the lab of Tamaki Ura. The ALBAC design uses a drop weight to drive the glider in a single dive cycle between deployment and recovery from ship. It uses a moving internal mass to control pitch and roll. 1993 Autonomous Oceanographic Sampling Networks paper appears in Oceanography
Development Timeline 1999 Slocum gliders tested at LEO-15 Observatory NJ 1999 Autonomous Ocean Sampling Network (AOSN) I conducted in Monterey Bay, CA to make oceanographic surveys. A prototype Spray
operates for 11 days. Three Seagliders were also deployed in the bay. 2000 By this time all three gliders, Spray, Slocum, and Seaglider, have completed 10 day missions 2001 Spray glider makes 280 km section from San Diego 2002 Seaglider travels 1000+ km off Washington Coast. Another Seaglider is deployed for month in storms off shelf near Seward Alaska 2003 January. Deployment of three Slocum gliders in the Bahamas by WHOI. Trials of prototype thermal Slocum conducted by WRC on same cruise
Development Timeline 2003 February. SPAWAR and the Canadian Navy conduct tests in the
Gullf of Mexico of 3 Slocum electric gliders. 2003 August September. AOSN II conducted in Monterey Bay CA. Gliders are used to make extensive oceanographic surveys over a six week period. Twelve Slocum and five Spray gliders are deployed during the experiment, to date the most gliders deployed for one project. 2004 September November. A Spray glider travels across the Gulf Stream, beginning about 100 miles south of Nantucket, MA and arriving near Bermuda about one month later. The glider travels 600 miles, at a speed of about 0.5 miles per hour or 12 miles per day. 2004 Sea Gliders operate through a typhoon off east Asia
2005 Two Sea Gliders fly from Washington coast to Hawaii 6 month mission 2005 Gliders launched from US Submarine Ocean Glider Census ~150 vehicles* Seaglider Spray Slocum
No. in use 22 8 35 No. used
in-house 22 8 15-20 12
No. on order * June 2006 50 Slocum Seaglider
Spray Dimensions Length 150cm Length 180cm, Diameter 21.3cm Diameter 30cm, Wingspan 100cm, Antenna 150cm Length 200cm, Diameter 20cm,
Wingspan 110cm Speed ~40 cm/s ~25 cm/s ~25-30 cm/s
Depth 4-200 meters 1000 meters 1500 meters Endurance
30 days 1-6 months 815 cycles to surface Power
Alkaline Battery LiSoCl2 battery, 10MJ, 24/10V packs 52 Li CSC cells Weight 52 kg
52 kg 51.8 kg Range 1,500 km 6,000 km
3500-4700 km Slocum Seaglider Spray Data Transmission
RF Modem, Iridium satellite Iridium satellite, data telemetry, ARGOS, AMPS Cellular Telesonar modem Range
1,500 km 6,000 km 3500-4700 km Navigation GPS, internal dead reckoning,
altimeter GPS-based dead reckoning, GPS, Iridium satellite Glide Angle
~35 degrees 8-70 degrees (1:5 - 3:1 slope) 19-25 degrees Slocum Gliders
Benefits cheaper to operate when cf with shipborne observations Operations in all weather Designed for launch, monitor, recover or launch, forget, recover missions Telemetry rates via low earth orbit satellites are sufficiently inexpensive in both energy (~30 J/kilobyte) and cost (~$0.20/kilobyte) that the data return from a single glider (~120 kilobytes/day) is nearly that originally envisioned for the entire 3000-float Argo fleet using ARGOS while being a
factor of ~200 less expensive. Gliders are tools for appropriate Missions Need to balance quality of data spatial requirements temporal requirements costs
to select best overall performance and value Glider mission can be changed at any time Sensor Capabilities
Temperature Conductivity Salinity Depth Wavelength backscatter Fluorescence sensor Beam attenuation
Passive Acoustics Real-time data available through the web Delayed mode calibrated, QC data available Slocum Electric Glider Manufactured by Webb Research, USA
Slocum Electric Glider SENSORS CTD (conductivity, temperature, depth) - SeaBird Dissolved oxygen Aanderaa Optode Fluorescence: Chlorophyll-a, CDOM (coloured dissolved organic matter), Phycoerythrin - Wetlabs Optical Backscatter:: turbidity through backscattered light at 470nm (blue), 530 nm (Green), 660nm (red). Slocum Electric Glider
Glider Path: 22 days, 486 km, 2420 profiles Depth-mean currents from glider Glider cross-section: Sepia depression Glider cross-section: Temperature Glider cross-section: Temperature
Glider cross-section: Density Glider cross-section: Backscatter Glider cross-section: Temperature Glider cross-section: Salinity Glider cross-section: Temperature
Glider cross-section: Salinity Glider cross-section: Density Glider cross-section: Density Investment plan Glider Purchase:
5 shallow (200m) and 5 deep (1000m) (30%) People: 3 people: glider preparation; Glider deployment and control; data provision (QC) (30%) Glider deployments: Data transmission costs, shipping (30%)
Schedule: 2 shallow water gliders to be delivered in June 2007 2 deep water gliders to be delivered in November 2007 Others to come onboard in 2008.