Presentation to Data Buoy Cooperation Panel XVII

1. PresentationtoData Buoy Cooperation Panel XVII J-CAD (JAMSTEC Compact Arctic Drifter)

2. Presentation Outline • Design Requirements • Sensors • Mechanical Characteristics • System Electronics • Data Telemetry • Testing • Deployments to Date • Conclusions DBCP XVII

3. Design Requirements • Reduce size, cost, and scope of observations from the buoys developed for the IOEB (Ice-Ocean Environmental Buoy) program • Use bi-directional ORBCOMM telemetry • Provide GPS positioning so that under ice-ocean currents can be measured • Use inductive modem system for all underwater sensors • Reduce weight to less than 250 kg so the buoy may be easily deployed using a small, light-weight crane • Provide underwater sensors less than 28 cm in diameter so 30 cm twist drill can be used for sensor deployments • Provide hourly measurements over a two-year operating lifetime DBCP XVII

4. DBCP XVII

5. J-CAD Sensors • Meteorological Sensors • YSI thermistor for air-temperature in a naturally aspirated, Gill-plated radiation shield • Paroscientific Model 216 B barometer with a METOCEAN-designed barometer port • RM Young Model 5106-MA propeller anemometer mounted about two meters above the ice • Oceanographic Sensors--data telemetry by Sea-Bird inductive modems • Two RDI WorkHorse 300 kHz ADCPs measuring 16 layers every 10 minutes • Downward facing unit at 12 m • Upward facing unit at 260 m • Six Sea-Bird SBE 37 IM CT sensors at 25 m, 80 m, 110 m, 180 m, and 250 m • Pressure data at 110 m and 250 m • Buoy Monitoring Sensors • Precision navigation, three-axis magnetometer for platform orientation • YSI thermistor on platform hull to provide sea-ice or seawater temperature • Jupiter Model TU30 12-channel GPS receiver DBCP XVII

6. J-CAD Mechanical Characteristics • Electronics Enclosure • 8-inch Sch 40 aluminum pipe acts as enclosure for electronics and lithium battery packs • RS-232 water-tight port for system testing and data download • Barometer port mast supports GPS and Argos antenna and air-temperature radiation shield • Floatation • Surlyn lonomer collar, manufactured by The Gilman Corporation, is highly resistant to damage by ice • J-CAD will float if ice breaks-up • Tripod Mast • Supports ORBCOMM antenna and propeller anomometer DBCP XVII

7. DBCP XVII

8. J-CAD System Electronics • System Controller • METOCEAN digital controller based on Model MAT 906 Argos PTT • Onset Computer Tattletale Model 8 data logger and master controller with 48 MB flash card memory • Modular design provides redundancy • Underwater Telemetry • Sea-Bird inductive modem with a single conductor, oceanographic cable • Tattletale 8 controller for data logging for all underwater sensors • Data Collection and Processing • METOCEAN controller handles all meteorological sensors, GPS, and Argos telemetry • Tattletale 8 controller handles central system time, underwater telemetry, and ORBCOMM telemetry • At approximately 10 minutes prior to the hour, sensor sampling commences • Data processing of all sensors begins at the top of the hour and proceeds for 10 minutes after the hour • Data is stored and then readied for transmission 15 minutes after the hour • Satellite Telemetry • ORBCOMM telemetry is the primary operational mode; Argos is the back-up mode • Power Supply • Two 245 Ahr lithium battery packs--one only for the ORBCOMM SC and the other for the rest of the system DBCP XVII

9. CTD #1 110 METERS IND COUPLED DBCP XVII

10. J-CAD Data Telemetry • ORBCOMM is the primary telemetry system • ORBCOMM SC is a Panasonic Model KX-G7101, with GPS capability, and uses 1/4 wave Sinclabs Model SRL-201 antenna • Single 192 byte ORBCOMM message is generated every hour, and three of these messages are sent every third hour • Argos telemetry is the back-up • Argos PTT is a METOCEAN Model MAT 906 and uses a 1/4 wave METOCEAN whip antenna • If 11 hours of ORBCOMM messages are accumulated without transmission, the Argos PTT begins to transmit Argos messages (6 Argos messages equals one ORBCOMM message) • Argos suspends transmission when ORBCOMM message accumulation is less than five hours DBCP XVII

11. J-CAD Testing • Functional system testing at the factory • All major subassemblies tested prior to system integration • All sensors and telemetry systems are tested • Limited failure mode testing • Bedford Basin, Nova Scotia • Complete system testing of one J-CAD, including oceanographic sensors • Practice system deployment • Seward, Alaska • Complete system testing (all three J-CADs) in a colder climate & higher latitude • Comparisons made to pier-mounted weather station • Barometric pressure data offsets due to tidal variation and height of pier • Practice system deployment • Deployment Site • Final verification that unit is working properly after installation • Freewave radio telemetry interface allowed this testing in “comfort” of a tent DBCP XVII

12. DBCP XVII

13. DBCP XVII

14. DBCP XVII

15. Deployments to Date • Three J-CAD systems have been deployed in the Arctic Ocean • Long-range plans anticipate two deployments per year--one at the North Pole and the second in the Beaufort Sea DBCP XVII

16. Conclusions • J-CAD is the first system to measure oceanographic sensors using an inductive modem system below the sea-ice • J-CAD was the first system to use ORBCOMM telemetry from the North Pole • J-CAD is a very cost-effective system for polar observations DBCP XVII