The PI's request funding to develop two instruments based upon an existing technology (off-axis integrated cavity optical spectroscopy, or ICOS): an in situ autonomous methane concentration and isotope analyzer and an in situ carbon dioxide concentration and isotope analyzer. ICOS technology has become extremely popular for gaseous quantification and isotopic analyses, and is supplanting traditional instruments such as isotope-ratio mass spectrometers. ICOS-based instruments are moderate in size and, when compared to mass spectrometers, require relatively little power. As such, they have been deployed in a wide range of challenging terrestrial and atmospheric environments, including tree canopies, weather balloons and NOAA aircraft. They are very resilient to moisture, changes in temperature and shock and vibration. With only one moving part (a diaphragm pump), the ICOS systems are very robust and do not expend tremendous energy on sample acquisition or processing. The PI?s have allied with Los Gatos Research Inc., the inventors and manufacturers of terrestrial ICOS instruments to adapt the existing instruments to an appropriate form for underwater deployment, and develop the additional technologies required to operate these instruments underwater In order to accomplish this, the PI?s are proposing to design a 6000 meter rated inlet system, design and develop a gas exhauster system (to allow for extremely long-term deployments), and interface the instrument to a seafloor cabled observatory. They plan to deploy the ICOS in three configurations: as an ROV or submersible-based instrument, a standalone instrument operating off battery packs, and as an integral component of a cabled observatory node. As part of this effort, they will work closely with Los Gatos Research Inc to commercialize this instrument within six months of completion of this project.
Broader Impacts:
If successful, this project has the potential to provide the oceanographic community with their first in situ methane and inorganic carbon isotope analyzers capable of high-resolution determinations of both concentration and isotopic composition. This will pave the way for further developments that leverage off ICOS technology, including in situ analyzers for many other gaseous analytes (e.g., N2O, CO, NH3, H, NO, H2S etc.). The project will involve participation of a postdoctoral fellow, graduate and undergraduate students.
