Carbon Wave Glider
Developing new platforms for carbon measurements
Use of this vehicle could lead to a new paradigm for economical underway surface observations that does not rely on expensive research ships and is not restricted to the standard shipping lanes of volunteer vessels.
The PMEL carbon group has teamed up with Liquid Robotics Inc. to integrate a MAPCO2 system, a SeaFET pH sensor and a SeaBird CTD into a Wave Glider vehicle. The Wave Glider represents an innovative approach to ocean persistent presence; it harnesses ocean wave energy to provide essentially limitless propulsion while solar panels continually replenish the batteries used to power the Wave Glider’s control electronics and payload systems. The Wave Glider vehicle is propelled by the purely mechanical conversion of ocean wave energy into forward thrust, independent of wave direction. Through extensive engineering trials and demonstrations, the Wave Glider’s capability for long-term autonomous operation in the open and coastal oceans has been firmly established. The Wave Glider has successfully circumnavigated the Big Island of Hawaii, surveyed West Coast of the North American from Canada to Mexico, and crossed the Pacific Ocean from Hawaii to San Diego.
The figure above shows a cut-away view of the integration of the MAPCO2 sensor onto the Wave Glider platform (Carbon Wave Glider, CWG). The resulting CWG will be capable both of conducting autonomous, basin-scale ocean transits to provide new insight into the spatial variability of carbon uptake and associated parameters and of acting as a long-duration (up to 6 months) "virtual mooring” to augment the existing sparse collection of moored carbon science sensors.
Two integrated CWG systems have been constructed and deployed out of Westport, WA for their maiden voyages on August 3, 2011. The two CWGs were operated side-by-side for two weeks as they traveled north to occupy an east-west survey line at 47°N. After two weeks of running together, one CWG was sent south to survey surface carbon concentrations off the southern Washington and Oregon coasts while the other continued to survey the northern Washington line.
The timing and location of the CWG deployment was coordinated to take advantage of the 2011 West Coast cruise which crossed with the CWGs several times. The CWGs were also navigated around several PMEL CO2 moorings (e.g. Cape Elizabeth, La Push) so the data from these different platforms can be compared. These crossings between the two CWGs, the CWGs and the research ship, and the CWGs and the buoys will be carefully examined over the next few months to evaluate the quality of the data collected.
The CWGs were recovered in September and will be redeployed in Hawaii where they will go to the Hawaii Ocean Time-series (HOT) site for a second data quality test in this stable subtropical open ocean environment.